Class: Redis

Inherits:
Object
  • Object
show all
Includes:
MonitorMixin
Defined in:
lib/redis.rb,
lib/redis/client.rb,
lib/redis/errors.rb,
lib/redis/cluster.rb,
lib/redis/version.rb,
lib/redis/pipeline.rb,
lib/redis/hash_ring.rb,
lib/redis/subscribe.rb,
lib/redis/distributed.rb,
lib/redis/cluster/key_slot_converter.rb

Defined Under Namespace

Classes: BaseConnectionError, BaseError, CannotConnectError, Client, Cluster, CommandError, ConnectionError, Distributed, Future, FutureNotReady, HashRing, InheritedError, Pipeline, ProtocolError, SubscribedClient, Subscription, TimeoutError

Constant Summary collapse

VERSION =
"4.0.0"

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Redis

Create a new client instance

Parameters:

  • options (Hash) (defaults to: {})

Options Hash (options):

  • :url (String) — default: value of the environment variable REDIS_URL

    a Redis URL, for a TCP connection: redis://:[password]@[hostname]:[port]/[db] (password, port and database are optional), for a unix socket connection: unix://[path to Redis socket]. This overrides all other options.

  • :host (String) — default: "127.0.0.1"

    server hostname

  • :port (Fixnum) — default: 6379

    server port

  • :path (String)

    path to server socket (overrides host and port)

  • :timeout (Float) — default: 5.0

    timeout in seconds

  • :connect_timeout (Float) — default: same as timeout

    timeout for initial connect in seconds

  • :password (String)

    Password to authenticate against server

  • :db (Fixnum) — default: 0

    Database to select after initial connect

  • :driver (Symbol)

    Driver to use, currently supported: :ruby, :hiredis, :synchrony

  • :id (String)

    ID for the client connection, assigns name to current connection by sending CLIENT SETNAME

  • :tcp_keepalive (Hash, Fixnum)

    Keepalive values, if Fixnum intvl and probe are calculated based on the value, if Hash time, intvl and probes can be specified as a Fixnum

  • :reconnect_attempts (Fixnum)

    Number of attempts trying to connect

  • :inherit_socket (Boolean) — default: false

    Whether to use socket in forked process or not

  • :sentinels (Array)

    List of sentinels to contact

  • :role (Symbol) — default: :master

    Role to fetch via Sentinel, either :master or :slave


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# File 'lib/redis.rb', line 36

def initialize(options = {})
  @options = options.dup
  @original_client = @client = Client.new(options)
  @queue = Hash.new { |h, k| h[k] = [] }

  super() # Monitor#initialize
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(command, *args) ⇒ Object


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# File 'lib/redis.rb', line 2740

def method_missing(command, *args)
  synchronize do |client|
    client.call([command] + args)
  end
end

Class Method Details

.currentObject


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# File 'lib/redis.rb', line 6

def self.current
  @current ||= Redis.new
end

.current=(redis) ⇒ Object


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# File 'lib/redis.rb', line 10

def self.current=(redis)
  @current = redis
end

Instance Method Details

#_bpop(cmd, args) ⇒ Object


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# File 'lib/redis.rb', line 1129

def _bpop(cmd, args)
  options = {}

  case args.last
  when Hash
    options = args.pop
  when Integer
    # Issue deprecation notice in obnoxious mode...
    options[:timeout] = args.pop
  end

  if args.size > 1
    # Issue deprecation notice in obnoxious mode...
  end

  keys = args.flatten
  timeout = options[:timeout] || 0

  synchronize do |client|
    command = [cmd, keys, timeout]
    timeout += client.timeout if timeout > 0
    client.call_with_timeout(command, timeout)
  end
end

#_clientObject


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# File 'lib/redis.rb', line 109

def _client
  @client
end

#_eval(cmd, args) ⇒ Object


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# File 'lib/redis.rb', line 2427

def _eval(cmd, args)
  script = args.shift
  options = args.pop if args.last.is_a?(Hash)
  options ||= {}

  keys = args.shift || options[:keys] || []
  argv = args.shift || options[:argv] || []

  synchronize do |client|
    client.call([cmd, script, keys.length] + keys + argv)
  end
end

#_scan(command, cursor, args, options = {}, &block) ⇒ Object


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# File 'lib/redis.rb', line 2490

def _scan(command, cursor, args, options = {}, &block)
  # SSCAN/ZSCAN/HSCAN already prepend the key to +args+.

  args << cursor

  if match = options[:match]
    args.concat(["MATCH", match])
  end

  if count = options[:count]
    args.concat(["COUNT", count])
  end

  synchronize do |client|
    client.call([command] + args, &block)
  end
end

#append(key, value) ⇒ Fixnum

Append a value to a key.

Parameters:

  • key (String)
  • value (String)

    value to append

Returns:

  • (Fixnum)

    length of the string after appending


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# File 'lib/redis.rb', line 970

def append(key, value)
  synchronize do |client|
    client.call([:append, key, value])
  end
end

#auth(password) ⇒ String

Authenticate to the server.

Parameters:

  • password (String)

    must match the password specified in the requirepass directive in the configuration file

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 118

def auth(password)
  synchronize do |client|
    client.call([:auth, password])
  end
end

#bgrewriteaofString

Asynchronously rewrite the append-only file.

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 172

def bgrewriteaof
  synchronize do |client|
    client.call([:bgrewriteaof])
  end
end

#bgsaveString

Asynchronously save the dataset to disk.

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 181

def bgsave
  synchronize do |client|
    client.call([:bgsave])
  end
end

#bitcount(key, start = 0, stop = -1)) ⇒ Fixnum

Count the number of set bits in a range of the string value stored at key.

Parameters:

  • key (String)
  • start (Fixnum) (defaults to: 0)

    start index

  • stop (Fixnum) (defaults to: -1))

    stop index

Returns:

  • (Fixnum)

    the number of bits set to 1


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# File 'lib/redis.rb', line 982

def bitcount(key, start = 0, stop = -1)
  synchronize do |client|
    client.call([:bitcount, key, start, stop])
  end
end

#bitop(operation, destkey, *keys) ⇒ Fixnum

Perform a bitwise operation between strings and store the resulting string in a key.

Parameters:

  • operation (String)

    e.g. and, or, xor, not

  • destkey (String)

    destination key

  • keys (String, Array<String>)

    one or more source keys to perform operation

Returns:

  • (Fixnum)

    the length of the string stored in destkey


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# File 'lib/redis.rb', line 994

def bitop(operation, destkey, *keys)
  synchronize do |client|
    client.call([:bitop, operation, destkey] + keys)
  end
end

#bitpos(key, bit, start = nil, stop = nil) ⇒ Fixnum

Return the position of the first bit set to 1 or 0 in a string.

Parameters:

  • key (String)
  • bit (Fixnum)

    whether to look for the first 1 or 0 bit

  • start (Fixnum) (defaults to: nil)

    start index

  • stop (Fixnum) (defaults to: nil)

    stop index

Returns:

  • (Fixnum)

    the position of the first 1/0 bit. -1 if looking for 1 and it is not found or start and stop are given.


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# File 'lib/redis.rb', line 1008

def bitpos(key, bit, start=nil, stop=nil)
  if stop and not start
    raise(ArgumentError, 'stop parameter specified without start parameter')
  end

  synchronize do |client|
    command = [:bitpos, key, bit]
    command << start if start
    command << stop if stop
    client.call(command)
  end
end

#blpop(*args) ⇒ nil, [String, String]

Remove and get the first element in a list, or block until one is available.

Examples:

With timeout

list, element = redis.blpop("list", :timeout => 5)
  # => nil on timeout
  # => ["list", "element"] on success

Without timeout

list, element = redis.blpop("list")
  # => ["list", "element"]

Blocking pop on multiple lists

list, element = redis.blpop(["list", "another_list"])
  # => ["list", "element"]

Parameters:

  • keys (String, Array<String>)

    one or more keys to perform the blocking pop on

  • options (Hash)
    • :timeout => Fixnum: timeout in seconds, defaults to no timeout

Returns:

  • (nil, [String, String])
    • nil when the operation timed out
    • tuple of the list that was popped from and element was popped otherwise

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# File 'lib/redis.rb', line 1175

def blpop(*args)
  _bpop(:blpop, args)
end

#brpop(*args) ⇒ nil, [String, String]

Remove and get the last element in a list, or block until one is available.

Parameters:

  • keys (String, Array<String>)

    one or more keys to perform the blocking pop on

  • options (Hash)
    • :timeout => Fixnum: timeout in seconds, defaults to no timeout

Returns:

  • (nil, [String, String])
    • nil when the operation timed out
    • tuple of the list that was popped from and element was popped otherwise

See Also:


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# File 'lib/redis.rb', line 1191

def brpop(*args)
  _bpop(:brpop, args)
end

#brpoplpush(source, destination, options = {}) ⇒ nil, String

Pop a value from a list, push it to another list and return it; or block until one is available.

Parameters:

  • source (String)

    source key

  • destination (String)

    destination key

  • options (Hash) (defaults to: {})
    • :timeout => Fixnum: timeout in seconds, defaults to no timeout

Returns:

  • (nil, String)
    • nil when the operation timed out
    • the element was popped and pushed otherwise

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# File 'lib/redis.rb', line 1206

def brpoplpush(source, destination, options = {})
  case options
  when Integer
    # Issue deprecation notice in obnoxious mode...
    options = { :timeout => options }
  end

  timeout = options[:timeout] || 0

  synchronize do |client|
    command = [:brpoplpush, source, destination, timeout]
    timeout += client.timeout if timeout > 0
    client.call_with_timeout(command, timeout)
  end
end

#call(*command) ⇒ Object

Sends a command to Redis and returns its reply.

Replies are converted to Ruby objects according to the RESP protocol, so you can expect a Ruby array, integer or nil when Redis sends one. Higher level transformations, such as converting an array of pairs into a Ruby hash, are up to consumers.

Redis error replies are raised as Ruby exceptions.


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# File 'lib/redis.rb', line 79

def call(*command)
  synchronize do |client|
    client.call(command)
  end
end

#client(subcommand = nil, *args) ⇒ String, Hash

Manage client connections.

Parameters:

  • subcommand (String, Symbol) (defaults to: nil)

    e.g. kill, list, getname, setname

Returns:

  • (String, Hash)

    depends on subcommand


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# File 'lib/redis.rb', line 208

def client(subcommand = nil, *args)
  synchronize do |client|
    client.call([:client, subcommand] + args) do |reply|
      if subcommand.to_s == "list"
        reply.lines.map do |line|
          entries = line.chomp.split(/[ =]/)
          Hash[entries.each_slice(2).to_a]
        end
      else
        reply
      end
    end
  end
end

#closeObject Also known as: disconnect!

Disconnect the client as quickly and silently as possible.


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# File 'lib/redis.rb', line 66

def close
  @original_client.disconnect
end

#commitObject

Sends all commands in the queue.

See http://redis.io/topics/pipelining for more details.


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# File 'lib/redis.rb', line 99

def commit
  synchronize do |client|
    begin
      client.call_pipelined(@queue[Thread.current.object_id])
    ensure
      @queue.delete(Thread.current.object_id)
    end
  end
end

#config(action, *args) ⇒ String, Hash

Get or set server configuration parameters.

Parameters:

  • action (Symbol)

    e.g. :get, :set, :resetstat

Returns:

  • (String, Hash)

    string reply, or hash when retrieving more than one property with CONFIG GET


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# File 'lib/redis.rb', line 192

def config(action, *args)
  synchronize do |client|
    client.call([:config, action] + args) do |reply|
      if reply.kind_of?(Array) && action == :get
        Hashify.call(reply)
      else
        reply
      end
    end
  end
end

#connected?Boolean

Test whether or not the client is connected

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 61

def connected?
  @original_client.connected?
end

#dbsizeFixnum

Return the number of keys in the selected database.

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 226

def dbsize
  synchronize do |client|
    client.call([:dbsize])
  end
end

#debug(*args) ⇒ Object


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# File 'lib/redis.rb', line 232

def debug(*args)
  synchronize do |client|
    client.call([:debug] + args)
  end
end

#decr(key) ⇒ Fixnum

Decrement the integer value of a key by one.

Examples:

redis.decr("value")
  # => 4

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    value after decrementing it


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# File 'lib/redis.rb', line 677

def decr(key)
  synchronize do |client|
    client.call([:decr, key])
  end
end

#decrby(key, decrement) ⇒ Fixnum

Decrement the integer value of a key by the given number.

Examples:

redis.decrby("value", 5)
  # => 0

Parameters:

  • key (String)
  • decrement (Fixnum)

Returns:

  • (Fixnum)

    value after decrementing it


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# File 'lib/redis.rb', line 692

def decrby(key, decrement)
  synchronize do |client|
    client.call([:decrby, key, decrement])
  end
end

#del(*keys) ⇒ Fixnum

Delete one or more keys.

Parameters:

  • keys (String, Array<String>)

Returns:

  • (Fixnum)

    number of keys that were deleted


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# File 'lib/redis.rb', line 509

def del(*keys)
  synchronize do |client|
    client.call([:del] + keys)
  end
end

#discardString

Discard all commands issued after MULTI.

Only call this method when #multi was called without a block.

Returns:

  • (String)

    "OK"

See Also:


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# File 'lib/redis.rb', line 2373

def discard
  synchronize do |client|
    client.call([:discard])
  end
end

#dump(key) ⇒ String

Return a serialized version of the value stored at a key.

Parameters:

  • key (String)

Returns:

  • (String)

    serialized_value


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# File 'lib/redis.rb', line 461

def dump(key)
  synchronize do |client|
    client.call([:dump, key])
  end
end

#dupObject


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# File 'lib/redis.rb', line 2736

def dup
  self.class.new(@options)
end

#echo(value) ⇒ String

Echo the given string.

Parameters:

  • value (String)

Returns:

  • (String)

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# File 'lib/redis.rb', line 149

def echo(value)
  synchronize do |client|
    client.call([:echo, value])
  end
end

#eval(*args) ⇒ Object

Evaluate Lua script.

Examples:

EVAL without KEYS nor ARGV

redis.eval("return 1")
  # => 1

EVAL with KEYS and ARGV as array arguments

redis.eval("return { KEYS, ARGV }", ["k1", "k2"], ["a1", "a2"])
  # => [["k1", "k2"], ["a1", "a2"]]

EVAL with KEYS and ARGV in a hash argument

redis.eval("return { KEYS, ARGV }", :keys => ["k1", "k2"], :argv => ["a1", "a2"])
  # => [["k1", "k2"], ["a1", "a2"]]

Parameters:

  • keys (Array<String>)

    optional array with keys to pass to the script

  • argv (Array<String>)

    optional array with arguments to pass to the script

  • options (Hash)
    • :keys => Array<String>: optional array with keys to pass to the script
    • :argv => Array<String>: optional array with arguments to pass to the script

Returns:

  • depends on the script

See Also:


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# File 'lib/redis.rb', line 2461

def eval(*args)
  _eval(:eval, args)
end

#evalsha(*args) ⇒ Object

Evaluate Lua script by its SHA.

Examples:

EVALSHA without KEYS nor ARGV

redis.evalsha(sha)
  # => <depends on script>

EVALSHA with KEYS and ARGV as array arguments

redis.evalsha(sha, ["k1", "k2"], ["a1", "a2"])
  # => <depends on script>

EVALSHA with KEYS and ARGV in a hash argument

redis.evalsha(sha, :keys => ["k1", "k2"], :argv => ["a1", "a2"])
  # => <depends on script>

Parameters:

  • keys (Array<String>)

    optional array with keys to pass to the script

  • argv (Array<String>)

    optional array with arguments to pass to the script

  • options (Hash)
    • :keys => Array<String>: optional array with keys to pass to the script
    • :argv => Array<String>: optional array with arguments to pass to the script

Returns:

  • depends on the script

See Also:


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# File 'lib/redis.rb', line 2486

def evalsha(*args)
  _eval(:evalsha, args)
end

#execnil, Array<...>

Execute all commands issued after MULTI.

Only call this method when #multi was called without a block.

Returns:

  • (nil, Array<...>)
    • when commands were not executed, nil
    • when commands were executed, an array with their replies

See Also:


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# File 'lib/redis.rb', line 2359

def exec
  synchronize do |client|
    client.call([:exec])
  end
end

#exists(key) ⇒ Boolean

Determine if a key exists.

Parameters:

  • key (String)

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 519

def exists(key)
  synchronize do |client|
    client.call([:exists, key], &Boolify)
  end
end

#expire(key, seconds) ⇒ Boolean

Set a key's time to live in seconds.

Parameters:

  • key (String)
  • seconds (Fixnum)

    time to live

Returns:

  • (Boolean)

    whether the timeout was set or not


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# File 'lib/redis.rb', line 383

def expire(key, seconds)
  synchronize do |client|
    client.call([:expire, key, seconds], &Boolify)
  end
end

#expireat(key, unix_time) ⇒ Boolean

Set the expiration for a key as a UNIX timestamp.

Parameters:

  • key (String)
  • unix_time (Fixnum)

    expiry time specified as a UNIX timestamp

Returns:

  • (Boolean)

    whether the timeout was set or not


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# File 'lib/redis.rb', line 394

def expireat(key, unix_time)
  synchronize do |client|
    client.call([:expireat, key, unix_time], &Boolify)
  end
end

#flushallString

Remove all keys from all databases.

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 241

def flushall
  synchronize do |client|
    client.call([:flushall])
  end
end

#flushdbString

Remove all keys from the current database.

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 250

def flushdb
  synchronize do |client|
    client.call([:flushdb])
  end
end

#get(key) ⇒ String

Get the value of a key.

Parameters:

  • key (String)

Returns:

  • (String)

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# File 'lib/redis.rb', line 875

def get(key)
  synchronize do |client|
    client.call([:get, key])
  end
end

#getbit(key, offset) ⇒ Fixnum

Returns the bit value at offset in the string value stored at key.

Parameters:

  • key (String)
  • offset (Fixnum)

    bit offset

Returns:

  • (Fixnum)

    0 or 1


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# File 'lib/redis.rb', line 959

def getbit(key, offset)
  synchronize do |client|
    client.call([:getbit, key, offset])
  end
end

#getrange(key, start, stop) ⇒ Fixnum

Get a substring of the string stored at a key.

Parameters:

  • key (String)
  • start (Fixnum)

    zero-based start offset

  • stop (Fixnum)

    zero-based end offset. Use -1 for representing the end of the string

Returns:

  • (Fixnum)

    0 or 1


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# File 'lib/redis.rb', line 936

def getrange(key, start, stop)
  synchronize do |client|
    client.call([:getrange, key, start, stop])
  end
end

#getset(key, value) ⇒ String

Set the string value of a key and return its old value.

Parameters:

  • key (String)
  • value (String)

    value to replace the current value with

Returns:

  • (String)

    the old value stored in the key, or nil if the key did not exist


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# File 'lib/redis.rb', line 1027

def getset(key, value)
  synchronize do |client|
    client.call([:getset, key, value.to_s])
  end
end

#hdel(key, field) ⇒ Fixnum

Delete one or more hash fields.

Parameters:

  • key (String)
  • field (String, Array<String>)

Returns:

  • (Fixnum)

    the number of fields that were removed from the hash


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# File 'lib/redis.rb', line 2093

def hdel(key, field)
  synchronize do |client|
    client.call([:hdel, key, field])
  end
end

#hexists(key, field) ⇒ Boolean

Determine if a hash field exists.

Parameters:

  • key (String)
  • field (String)

Returns:

  • (Boolean)

    whether or not the field exists in the hash


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# File 'lib/redis.rb', line 2104

def hexists(key, field)
  synchronize do |client|
    client.call([:hexists, key, field], &Boolify)
  end
end

#hget(key, field) ⇒ String

Get the value of a hash field.

Parameters:

  • key (String)
  • field (String)

Returns:

  • (String)

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# File 'lib/redis.rb', line 2044

def hget(key, field)
  synchronize do |client|
    client.call([:hget, key, field])
  end
end

#hgetall(key) ⇒ Hash<String, String>

Get all the fields and values in a hash.

Parameters:

  • key (String)

Returns:

  • (Hash<String, String>)

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# File 'lib/redis.rb', line 2158

def hgetall(key)
  synchronize do |client|
    client.call([:hgetall, key], &Hashify)
  end
end

#hincrby(key, field, increment) ⇒ Fixnum

Increment the integer value of a hash field by the given integer number.

Parameters:

  • key (String)
  • field (String)
  • increment (Fixnum)

Returns:

  • (Fixnum)

    value of the field after incrementing it


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# File 'lib/redis.rb', line 2116

def hincrby(key, field, increment)
  synchronize do |client|
    client.call([:hincrby, key, field, increment])
  end
end

#hincrbyfloat(key, field, increment) ⇒ Float

Increment the numeric value of a hash field by the given float number.

Parameters:

  • key (String)
  • field (String)
  • increment (Float)

Returns:

  • (Float)

    value of the field after incrementing it


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# File 'lib/redis.rb', line 2128

def hincrbyfloat(key, field, increment)
  synchronize do |client|
    client.call([:hincrbyfloat, key, field, increment], &Floatify)
  end
end

#hkeys(key) ⇒ Array<String>

Get all the fields in a hash.

Parameters:

  • key (String)

Returns:

  • (Array<String>)

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# File 'lib/redis.rb', line 2138

def hkeys(key)
  synchronize do |client|
    client.call([:hkeys, key])
  end
end

#hlen(key) ⇒ Fixnum

Get the number of fields in a hash.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    number of fields in the hash


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# File 'lib/redis.rb', line 1977

def hlen(key)
  synchronize do |client|
    client.call([:hlen, key])
  end
end

#hmget(key, *fields, &blk) ⇒ Array<String>

Get the values of all the given hash fields.

Examples:

redis.hmget("hash", "f1", "f2")
  # => ["v1", "v2"]

Parameters:

  • key (String)
  • fields (Array<String>)

    array of fields

Returns:

  • (Array<String>)

    an array of values for the specified fields

See Also:


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# File 'lib/redis.rb', line 2061

def hmget(key, *fields, &blk)
  synchronize do |client|
    client.call([:hmget, key] + fields, &blk)
  end
end

#hmset(key, *attrs) ⇒ String

Set one or more hash values.

Examples:

redis.hmset("hash", "f1", "v1", "f2", "v2")
  # => "OK"

Parameters:

  • key (String)
  • attrs (Array<String>)

    array of fields and values

Returns:

  • (String)

    "OK"

See Also:


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# File 'lib/redis.rb', line 2018

def hmset(key, *attrs)
  synchronize do |client|
    client.call([:hmset, key] + attrs)
  end
end

#hscan(key, cursor, options = {}) ⇒ String, Array<[String, String]>

Scan a hash

Examples:

Retrieve the first batch of key/value pairs in a hash

redis.hscan("hash", 0)

Parameters:

  • cursor (String, Integer)

    the cursor of the iteration

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (String, Array<[String, String]>)

    the next cursor and all found keys


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# File 'lib/redis.rb', line 2563

def hscan(key, cursor, options={})
  _scan(:hscan, cursor, [key], options) do |reply|
    [reply[0], reply[1].each_slice(2).to_a]
  end
end

#hscan_each(key, options = {}, &block) ⇒ Enumerator

Scan a hash

Examples:

Retrieve all of the key/value pairs in a hash

redis.hscan_each("hash").to_a
# => [["key70", "70"], ["key80", "80"]]

Parameters:

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (Enumerator)

    an enumerator for all found keys


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# File 'lib/redis.rb', line 2580

def hscan_each(key, options={}, &block)
  return to_enum(:hscan_each, key, options) unless block_given?
  cursor = 0
  loop do
    cursor, values = hscan(key, cursor, options)
    values.each(&block)
    break if cursor == "0"
  end
end

#hset(key, field, value) ⇒ Boolean

Set the string value of a hash field.

Parameters:

  • key (String)
  • field (String)
  • value (String)

Returns:

  • (Boolean)

    whether or not the field was added to the hash


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# File 'lib/redis.rb', line 1989

def hset(key, field, value)
  synchronize do |client|
    client.call([:hset, key, field, value], &Boolify)
  end
end

#hsetnx(key, field, value) ⇒ Boolean

Set the value of a hash field, only if the field does not exist.

Parameters:

  • key (String)
  • field (String)
  • value (String)

Returns:

  • (Boolean)

    whether or not the field was added to the hash


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# File 'lib/redis.rb', line 2001

def hsetnx(key, field, value)
  synchronize do |client|
    client.call([:hsetnx, key, field, value], &Boolify)
  end
end

#hvals(key) ⇒ Array<String>

Get all the values in a hash.

Parameters:

  • key (String)

Returns:

  • (Array<String>)

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# File 'lib/redis.rb', line 2148

def hvals(key)
  synchronize do |client|
    client.call([:hvals, key])
  end
end

#idObject


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# File 'lib/redis.rb', line 2728

def id
  @original_client.id
end

#incr(key) ⇒ Fixnum

Increment the integer value of a key by one.

Examples:

redis.incr("value")
  # => 6

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    value after incrementing it


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# File 'lib/redis.rb', line 706

def incr(key)
  synchronize do |client|
    client.call([:incr, key])
  end
end

#incrby(key, increment) ⇒ Fixnum

Increment the integer value of a key by the given integer number.

Examples:

redis.incrby("value", 5)
  # => 10

Parameters:

  • key (String)
  • increment (Fixnum)

Returns:

  • (Fixnum)

    value after incrementing it


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# File 'lib/redis.rb', line 721

def incrby(key, increment)
  synchronize do |client|
    client.call([:incrby, key, increment])
  end
end

#incrbyfloat(key, increment) ⇒ Float

Increment the numeric value of a key by the given float number.

Examples:

redis.incrbyfloat("value", 1.23)
  # => 1.23

Parameters:

  • key (String)
  • increment (Float)

Returns:

  • (Float)

    value after incrementing it


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# File 'lib/redis.rb', line 736

def incrbyfloat(key, increment)
  synchronize do |client|
    client.call([:incrbyfloat, key, increment], &Floatify)
  end
end

#info(cmd = nil) ⇒ Hash<String, String>

Get information and statistics about the server.

Parameters:

  • cmd (String, Symbol) (defaults to: nil)

    e.g. "commandstats"

Returns:

  • (Hash<String, String>)

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# File 'lib/redis.rb', line 260

def info(cmd = nil)
  synchronize do |client|
    client.call([:info, cmd].compact) do |reply|
      if reply.kind_of?(String)
        reply = Hash[reply.split("\r\n").map do |line|
          line.split(":", 2) unless line =~ /^(#|$)/
        end.compact]

        if cmd && cmd.to_s == "commandstats"
          # Extract nested hashes for INFO COMMANDSTATS
          reply = Hash[reply.map do |k, v|
            v = v.split(",").map { |e| e.split("=") }
            [k[/^cmdstat_(.*)$/, 1], Hash[v]]
          end]
        end
      end

      reply
    end
  end
end

#inspectObject


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# File 'lib/redis.rb', line 2732

def inspect
  "#<Redis client v#{Redis::VERSION} for #{id}>"
end

#keys(pattern = "*") ⇒ Array<String>

Find all keys matching the given pattern.

Parameters:

  • pattern (String) (defaults to: "*")

Returns:

  • (Array<String>)

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# File 'lib/redis.rb', line 529

def keys(pattern = "*")
  synchronize do |client|
    client.call([:keys, pattern]) do |reply|
      if reply.kind_of?(String)
        reply.split(" ")
      else
        reply
      end
    end
  end
end

#lastsaveFixnum

Get the UNIX time stamp of the last successful save to disk.

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 285

def lastsave
  synchronize do |client|
    client.call([:lastsave])
  end
end

#lindex(key, index) ⇒ String

Get an element from a list by its index.

Parameters:

  • key (String)
  • index (Fixnum)

Returns:

  • (String)

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# File 'lib/redis.rb', line 1227

def lindex(key, index)
  synchronize do |client|
    client.call([:lindex, key, index])
  end
end

#linsert(key, where, pivot, value) ⇒ Fixnum

Insert an element before or after another element in a list.

Parameters:

  • key (String)
  • where (String, Symbol)

    BEFORE or AFTER

  • pivot (String)

    reference element

  • value (String)

Returns:

  • (Fixnum)

    length of the list after the insert operation, or -1 when the element pivot was not found


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# File 'lib/redis.rb', line 1241

def linsert(key, where, pivot, value)
  synchronize do |client|
    client.call([:linsert, key, where, pivot, value])
  end
end

#llen(key) ⇒ Fixnum

Get the length of a list.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 1048

def llen(key)
  synchronize do |client|
    client.call([:llen, key])
  end
end

#lpop(key) ⇒ String

Remove and get the first element in a list.

Parameters:

  • key (String)

Returns:

  • (String)

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# File 'lib/redis.rb', line 1102

def lpop(key)
  synchronize do |client|
    client.call([:lpop, key])
  end
end

#lpush(key, value) ⇒ Fixnum

Prepend one or more values to a list, creating the list if it doesn't exist

Parameters:

  • key (String)
  • value (String, Array<String>)

    string value, or array of string values to push

Returns:

  • (Fixnum)

    the length of the list after the push operation


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# File 'lib/redis.rb', line 1059

def lpush(key, value)
  synchronize do |client|
    client.call([:lpush, key, value])
  end
end

#lpushx(key, value) ⇒ Fixnum

Prepend a value to a list, only if the list exists.

Parameters:

  • key (String)
  • value (String)

Returns:

  • (Fixnum)

    the length of the list after the push operation


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# File 'lib/redis.rb', line 1070

def lpushx(key, value)
  synchronize do |client|
    client.call([:lpushx, key, value])
  end
end

#lrange(key, start, stop) ⇒ Array<String>

Get a range of elements from a list.

Parameters:

  • key (String)
  • start (Fixnum)

    start index

  • stop (Fixnum)

    stop index

Returns:

  • (Array<String>)

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# File 'lib/redis.rb', line 1253

def lrange(key, start, stop)
  synchronize do |client|
    client.call([:lrange, key, start, stop])
  end
end

#lrem(key, count, value) ⇒ Fixnum

Remove elements from a list.

Parameters:

  • key (String)
  • count (Fixnum)

    number of elements to remove. Use a positive value to remove the first count occurrences of value. A negative value to remove the last count occurrences of value. Or zero, to remove all occurrences of value from the list.

  • value (String)

Returns:

  • (Fixnum)

    the number of removed elements


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# File 'lib/redis.rb', line 1268

def lrem(key, count, value)
  synchronize do |client|
    client.call([:lrem, key, count, value])
  end
end

#lset(key, index, value) ⇒ String

Set the value of an element in a list by its index.

Parameters:

  • key (String)
  • index (Fixnum)
  • value (String)

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 1280

def lset(key, index, value)
  synchronize do |client|
    client.call([:lset, key, index, value])
  end
end

#ltrim(key, start, stop) ⇒ String

Trim a list to the specified range.

Parameters:

  • key (String)
  • start (Fixnum)

    start index

  • stop (Fixnum)

    stop index

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 1292

def ltrim(key, start, stop)
  synchronize do |client|
    client.call([:ltrim, key, start, stop])
  end
end

#mapped_hmget(key, *fields) ⇒ Hash

Get the values of all the given hash fields.

Examples:

redis.mapped_hmget("hash", "f1", "f2")
  # => { "f1" => "v1", "f2" => "v2" }

Parameters:

  • key (String)
  • fields (Array<String>)

    array of fields

Returns:

  • (Hash)

    a hash mapping the specified fields to their values

See Also:


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# File 'lib/redis.rb', line 2078

def mapped_hmget(key, *fields)
  hmget(key, *fields) do |reply|
    if reply.kind_of?(Array)
      Hash[fields.zip(reply)]
    else
      reply
    end
  end
end

#mapped_hmset(key, hash) ⇒ String

Set one or more hash values.

Examples:

redis.mapped_hmset("hash", { "f1" => "v1", "f2" => "v2" })
  # => "OK"

Parameters:

  • key (String)
  • hash (Hash)

    a non-empty hash with fields mapping to values

Returns:

  • (String)

    "OK"

See Also:


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# File 'lib/redis.rb', line 2035

def mapped_hmset(key, hash)
  hmset(key, hash.to_a.flatten)
end

#mapped_mget(*keys) ⇒ Hash

Get the values of all the given keys.

Examples:

redis.mapped_mget("key1", "key2")
  # => { "key1" => "v1", "key2" => "v2" }

Parameters:

  • keys (Array<String>)

    array of keys

Returns:

  • (Hash)

    a hash mapping the specified keys to their values

See Also:


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# File 'lib/redis.rb', line 907

def mapped_mget(*keys)
  mget(*keys) do |reply|
    if reply.kind_of?(Array)
      Hash[keys.zip(reply)]
    else
      reply
    end
  end
end

#mapped_mset(hash) ⇒ String

Set one or more values.

Examples:

redis.mapped_mset({ "f1" => "v1", "f2" => "v2" })
  # => "OK"

Parameters:

  • hash (Hash)

    keys mapping to values

Returns:

  • (String)

    "OK"

See Also:


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# File 'lib/redis.rb', line 837

def mapped_mset(hash)
  mset(hash.to_a.flatten)
end

#mapped_msetnx(hash) ⇒ Boolean

Set one or more values, only if none of the keys exist.

Examples:

redis.mapped_msetnx({ "key1" => "v1", "key2" => "v2" })
  # => true

Parameters:

  • hash (Hash)

    keys mapping to values

Returns:

  • (Boolean)

    whether or not all values were set

See Also:


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# File 'lib/redis.rb', line 867

def mapped_msetnx(hash)
  msetnx(hash.to_a.flatten)
end

#mget(*keys, &blk) ⇒ Array<String>

Get the values of all the given keys.

Examples:

redis.mget("key1", "key1")
  # => ["v1", "v2"]

Parameters:

  • keys (Array<String>)

Returns:

  • (Array<String>)

    an array of values for the specified keys

See Also:


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# File 'lib/redis.rb', line 891

def mget(*keys, &blk)
  synchronize do |client|
    client.call([:mget] + keys, &blk)
  end
end

#migrate(key, options) ⇒ String

Transfer a key from the connected instance to another instance.

Parameters:

  • key (String)
  • options (Hash)
    • :host => String: host of instance to migrate to
    • :port => Integer: port of instance to migrate to
    • :db => Integer: database to migrate to (default: same as source)
    • :timeout => Integer: timeout (default: same as connection timeout)

Returns:

  • (String)

    "OK"


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# File 'lib/redis.rb', line 494

def migrate(key, options)
  host = options[:host] || raise(RuntimeError, ":host not specified")
  port = options[:port] || raise(RuntimeError, ":port not specified")
  db = (options[:db] || @client.db).to_i
  timeout = (options[:timeout] || @client.timeout).to_i

  synchronize do |client|
    client.call([:migrate, host, port, key, db, timeout])
  end
end

#monitor {|line| ... } ⇒ Object

Listen for all requests received by the server in real time.

There is no way to interrupt this command.

Yields:

  • a block to be called for every line of output

Yield Parameters:

  • line (String)

    timestamp and command that was executed


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# File 'lib/redis.rb', line 297

def monitor(&block)
  synchronize do |client|
    client.call_loop([:monitor], &block)
  end
end

#move(key, db) ⇒ Boolean

Move a key to another database.

Examples:

Move a key to another database

redis.set "foo", "bar"
  # => "OK"
redis.move "foo", 2
  # => true
redis.exists "foo"
  # => false
redis.select 2
  # => "OK"
redis.exists "foo"
  # => true
redis.get "foo"
  # => "bar"

Parameters:

  • key (String)
  • db (Fixnum)

Returns:

  • (Boolean)

    whether the key was moved or not


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# File 'lib/redis.rb', line 560

def move(key, db)
  synchronize do |client|
    client.call([:move, key, db], &Boolify)
  end
end

#mset(*args) ⇒ String

Set one or more values.

Examples:

redis.mset("key1", "v1", "key2", "v2")
  # => "OK"

Parameters:

  • args (Array<String>)

    array of keys and values

Returns:

  • (String)

    "OK"

See Also:


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# File 'lib/redis.rb', line 821

def mset(*args)
  synchronize do |client|
    client.call([:mset] + args)
  end
end

#msetnx(*args) ⇒ Boolean

Set one or more values, only if none of the keys exist.

Examples:

redis.msetnx("key1", "v1", "key2", "v2")
  # => true

Parameters:

  • args (Array<String>)

    array of keys and values

Returns:

  • (Boolean)

    whether or not all values were set

See Also:


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# File 'lib/redis.rb', line 851

def msetnx(*args)
  synchronize do |client|
    client.call([:msetnx] + args, &Boolify)
  end
end

#multi {|multi| ... } ⇒ String, Array<...>

Mark the start of a transaction block.

Passing a block is optional.

Examples:

With a block

redis.multi do |multi|
  multi.set("key", "value")
  multi.incr("counter")
end # => ["OK", 6]

Without a block

redis.multi
  # => "OK"
redis.set("key", "value")
  # => "QUEUED"
redis.incr("counter")
  # => "QUEUED"
redis.exec
  # => ["OK", 6]

Yields:

  • (multi)

    the commands that are called inside this block are cached and written to the server upon returning from it

Yield Parameters:

Returns:

  • (String, Array<...>)
    • when a block is not given, OK
    • when a block is given, an array with replies

See Also:


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# File 'lib/redis.rb', line 2332

def multi
  synchronize do |client|
    if !block_given?
      client.call([:multi])
    else
      begin
        pipeline = Pipeline::Multi.new
        original, @client = @client, pipeline
        yield(self)
        original.call_pipeline(pipeline)
      ensure
        @client = original
      end
    end
  end
end

#object(*args) ⇒ Object


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# File 'lib/redis.rb', line 566

def object(*args)
  synchronize do |client|
    client.call([:object] + args)
  end
end

#persist(key) ⇒ Boolean

Remove the expiration from a key.

Parameters:

  • key (String)

Returns:

  • (Boolean)

    whether the timeout was removed or not


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# File 'lib/redis.rb', line 372

def persist(key)
  synchronize do |client|
    client.call([:persist, key], &Boolify)
  end
end

#pexpire(key, milliseconds) ⇒ Boolean

Set a key's time to live in milliseconds.

Parameters:

  • key (String)
  • milliseconds (Fixnum)

    time to live

Returns:

  • (Boolean)

    whether the timeout was set or not


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# File 'lib/redis.rb', line 423

def pexpire(key, milliseconds)
  synchronize do |client|
    client.call([:pexpire, key, milliseconds], &Boolify)
  end
end

#pexpireat(key, ms_unix_time) ⇒ Boolean

Set the expiration for a key as number of milliseconds from UNIX Epoch.

Parameters:

  • key (String)
  • ms_unix_time (Fixnum)

    expiry time specified as number of milliseconds from UNIX Epoch.

Returns:

  • (Boolean)

    whether the timeout was set or not


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# File 'lib/redis.rb', line 434

def pexpireat(key, ms_unix_time)
  synchronize do |client|
    client.call([:pexpireat, key, ms_unix_time], &Boolify)
  end
end

#pfadd(key, member) ⇒ Boolean

Add one or more members to a HyperLogLog structure.

Parameters:

  • key (String)
  • member (String, Array<String>)

    one member, or array of members

Returns:

  • (Boolean)

    true if at least 1 HyperLogLog internal register was altered. false otherwise.


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# File 'lib/redis.rb', line 2670

def pfadd(key, member)
  synchronize do |client|
    client.call([:pfadd, key, member], &Boolify)
  end
end

#pfcount(*keys) ⇒ Fixnum

Get the approximate cardinality of members added to HyperLogLog structure.

If called with multiple keys, returns the approximate cardinality of the union of the HyperLogLogs contained in the keys.

Parameters:

  • keys (String, Array<String>)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 2683

def pfcount(*keys)
  synchronize do |client|
    client.call([:pfcount] + keys)
  end
end

#pfmerge(dest_key, *source_key) ⇒ Boolean

Merge multiple HyperLogLog values into an unique value that will approximate the cardinality of the union of the observed Sets of the source HyperLogLog structures.

Parameters:

  • dest_key (String)

    destination key

  • source_key (String, Array<String>)

    source key, or array of keys

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 2695

def pfmerge(dest_key, *source_key)
  synchronize do |client|
    client.call([:pfmerge, dest_key, *source_key], &BoolifySet)
  end
end

#ping(message = nil) ⇒ String

Ping the server.

Parameters:

  • message (optional, String) (defaults to: nil)

Returns:

  • (String)

    PONG


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# File 'lib/redis.rb', line 139

def ping(message = nil)
  synchronize do |client|
    client.call([:ping, message].compact)
  end
end

#pipelinedObject


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# File 'lib/redis.rb', line 2290

def pipelined
  synchronize do |client|
    begin
      original, @client = @client, Pipeline.new
      yield(self)
      original.call_pipeline(@client)
    ensure
      @client = original
    end
  end
end

#psetex(key, ttl, value) ⇒ String

Set the time to live in milliseconds of a key.

Parameters:

  • key (String)
  • ttl (Fixnum)
  • value (String)

Returns:

  • (String)

    "OK"


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# File 'lib/redis.rb', line 794

def psetex(key, ttl, value)
  synchronize do |client|
    client.call([:psetex, key, ttl, value.to_s])
  end
end

#psubscribe(*channels, &block) ⇒ Object

Listen for messages published to channels matching the given patterns.


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# File 'lib/redis.rb', line 2200

def psubscribe(*channels, &block)
  synchronize do |client|
    _subscription(:psubscribe, 0, channels, block)
  end
end

#psubscribe_with_timeout(timeout, *channels, &block) ⇒ Object

Listen for messages published to channels matching the given patterns. Throw a timeout error if there is no messages for a timeout period.


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# File 'lib/redis.rb', line 2207

def psubscribe_with_timeout(timeout, *channels, &block)
  synchronize do |client|
    _subscription(:psubscribe_with_timeout, timeout, channels, block)
  end
end

#pttl(key) ⇒ Fixnum

Get the time to live (in milliseconds) for a key.

In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.

Starting with Redis 2.8 the return value in case of error changed:

- The command returns -2 if the key does not exist.
- The command returns -1 if the key exists but has no associated expire.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    remaining time to live in milliseconds


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# File 'lib/redis.rb', line 451

def pttl(key)
  synchronize do |client|
    client.call([:pttl, key])
  end
end

#publish(channel, message) ⇒ Object

Post a message to a channel.


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# File 'lib/redis.rb', line 2165

def publish(channel, message)
  synchronize do |client|
    client.call([:publish, channel, message])
  end
end

#pubsub(subcommand, *args) ⇒ Object

Inspect the state of the Pub/Sub subsystem. Possible subcommands: channels, numsub, numpat.


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# File 'lib/redis.rb', line 2223

def pubsub(subcommand, *args)
  synchronize do |client|
    client.call([:pubsub, subcommand] + args)
  end
end

#punsubscribe(*channels) ⇒ Object

Stop listening for messages posted to channels matching the given patterns.


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# File 'lib/redis.rb', line 2214

def punsubscribe(*channels)
  synchronize do |client|
    raise RuntimeError, "Can't unsubscribe if not subscribed." unless subscribed?
    client.punsubscribe(*channels)
  end
end

#queue(*command) ⇒ Object

Queues a command for pipelining.

Commands in the queue are executed with the Redis#commit method.

See http://redis.io/topics/pipelining for more details.


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# File 'lib/redis.rb', line 91

def queue(*command)
  @queue[Thread.current.object_id] << command
end

#quitString

Close the connection.

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 158

def quit
  synchronize do |client|
    begin
      client.call([:quit])
    rescue ConnectionError
    ensure
      client.disconnect
    end
  end
end

#randomkeyString

Return a random key from the keyspace.

Returns:

  • (String)

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# File 'lib/redis.rb', line 575

def randomkey
  synchronize do |client|
    client.call([:randomkey])
  end
end

#rename(old_name, new_name) ⇒ String

Rename a key. If the new key already exists it is overwritten.

Parameters:

  • old_name (String)
  • new_name (String)

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 586

def rename(old_name, new_name)
  synchronize do |client|
    client.call([:rename, old_name, new_name])
  end
end

#renamenx(old_name, new_name) ⇒ Boolean

Rename a key, only if the new key does not exist.

Parameters:

  • old_name (String)
  • new_name (String)

Returns:

  • (Boolean)

    whether the key was renamed or not


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# File 'lib/redis.rb', line 597

def renamenx(old_name, new_name)
  synchronize do |client|
    client.call([:renamenx, old_name, new_name], &Boolify)
  end
end

#restore(key, ttl, serialized_value, options = {}) ⇒ String

Create a key using the serialized value, previously obtained using DUMP.

Parameters:

  • key (String)
  • ttl (String)
  • serialized_value (String)
  • options (Hash) (defaults to: {})
    • :replace => Boolean: if false, raises an error if key already exists

Returns:

  • (String)

    "OK"

Raises:


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# File 'lib/redis.rb', line 476

def restore(key, ttl, serialized_value, options = {})
  args = [:restore, key, ttl, serialized_value]
  args << 'REPLACE' if options[:replace]

  synchronize do |client|
    client.call(args)
  end
end

#rpop(key) ⇒ String

Remove and get the last element in a list.

Parameters:

  • key (String)

Returns:

  • (String)

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# File 'lib/redis.rb', line 1112

def rpop(key)
  synchronize do |client|
    client.call([:rpop, key])
  end
end

#rpoplpush(source, destination) ⇒ nil, String

Remove the last element in a list, append it to another list and return it.

Parameters:

  • source (String)

    source key

  • destination (String)

    destination key

Returns:

  • (nil, String)

    the element, or nil when the source key does not exist


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# File 'lib/redis.rb', line 1123

def rpoplpush(source, destination)
  synchronize do |client|
    client.call([:rpoplpush, source, destination])
  end
end

#rpush(key, value) ⇒ Fixnum

Append one or more values to a list, creating the list if it doesn't exist

Parameters:

  • key (String)
  • value (String, Array<String>)

    string value, or array of string values to push

Returns:

  • (Fixnum)

    the length of the list after the push operation


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# File 'lib/redis.rb', line 1081

def rpush(key, value)
  synchronize do |client|
    client.call([:rpush, key, value])
  end
end

#rpushx(key, value) ⇒ Fixnum

Append a value to a list, only if the list exists.

Parameters:

  • key (String)
  • value (String)

Returns:

  • (Fixnum)

    the length of the list after the push operation


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# File 'lib/redis.rb', line 1092

def rpushx(key, value)
  synchronize do |client|
    client.call([:rpushx, key, value])
  end
end

#sadd(key, member) ⇒ Boolean, Fixnum

Add one or more members to a set.

Parameters:

  • key (String)
  • member (String, Array<String>)

    one member, or array of members

Returns:

  • (Boolean, Fixnum)

    Boolean when a single member is specified, holding whether or not adding the member succeeded, or Fixnum when an array of members is specified, holding the number of members that were successfully added


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# File 'lib/redis.rb', line 1316

def sadd(key, member)
  synchronize do |client|
    client.call([:sadd, key, member]) do |reply|
      if member.is_a? Array
        # Variadic: return integer
        reply
      else
        # Single argument: return boolean
        Boolify.call(reply)
      end
    end
  end
end

#saveString

Synchronously save the dataset to disk.

Returns:

  • (String)

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# File 'lib/redis.rb', line 306

def save
  synchronize do |client|
    client.call([:save])
  end
end

#scan(cursor, options = {}) ⇒ String+

Scan the keyspace

Examples:

Retrieve the first batch of keys

redis.scan(0)
  # => ["4", ["key:21", "key:47", "key:42"]]

Retrieve a batch of keys matching a pattern

redis.scan(4, :match => "key:1?")
  # => ["92", ["key:13", "key:18"]]

Parameters:

  • cursor (String, Integer)

    the cursor of the iteration

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (String, Array<String>)

    the next cursor and all found keys


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# File 'lib/redis.rb', line 2523

def scan(cursor, options={})
  _scan(:scan, cursor, [], options)
end

#scan_each(options = {}, &block) ⇒ Enumerator

Scan the keyspace

Examples:

Retrieve all of the keys (with possible duplicates)

redis.scan_each.to_a
  # => ["key:21", "key:47", "key:42"]

Execute block for each key matching a pattern

redis.scan_each(:match => "key:1?") {|key| puts key}
  # => key:13
  # => key:18

Parameters:

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (Enumerator)

    an enumerator for all found keys


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# File 'lib/redis.rb', line 2542

def scan_each(options={}, &block)
  return to_enum(:scan_each, options) unless block_given?
  cursor = 0
  loop do
    cursor, keys = scan(cursor, options)
    keys.each(&block)
    break if cursor == "0"
  end
end

#scard(key) ⇒ Fixnum

Get the number of members in a set.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 1302

def scard(key)
  synchronize do |client|
    client.call([:scard, key])
  end
end

#script(subcommand, *args) ⇒ String, ...

Control remote script registry.

Examples:

Load a script

sha = redis.script(:load, "return 1")
  # => <sha of this script>

Check if a script exists

redis.script(:exists, sha)
  # => true

Check if multiple scripts exist

redis.script(:exists, [sha, other_sha])
  # => [true, false]

Flush the script registry

redis.script(:flush)
  # => "OK"

Kill a running script

redis.script(:kill)
  # => "OK"

Parameters:

  • subcommand (String)

    e.g. exists, flush, load, kill

  • args (Array<String>)

    depends on subcommand

Returns:

  • (String, Boolean, Array<Boolean>, ...)

    depends on subcommand

See Also:


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# File 'lib/redis.rb', line 2403

def script(subcommand, *args)
  subcommand = subcommand.to_s.downcase

  if subcommand == "exists"
    synchronize do |client|
      arg = args.first

      client.call([:script, :exists, arg]) do |reply|
        reply = reply.map { |r| Boolify.call(r) }

        if arg.is_a?(Array)
          reply
        else
          reply.first
        end
      end
    end
  else
    synchronize do |client|
      client.call([:script, subcommand] + args)
    end
  end
end

#sdiff(*keys) ⇒ Array<String>

Subtract multiple sets.

Parameters:

  • keys (String, Array<String>)

    keys pointing to sets to subtract

Returns:

  • (Array<String>)

    members in the difference


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# File 'lib/redis.rb', line 1419

def sdiff(*keys)
  synchronize do |client|
    client.call([:sdiff] + keys)
  end
end

#sdiffstore(destination, *keys) ⇒ Fixnum

Subtract multiple sets and store the resulting set in a key.

Parameters:

  • destination (String)

    destination key

  • keys (String, Array<String>)

    keys pointing to sets to subtract

Returns:

  • (Fixnum)

    number of elements in the resulting set


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# File 'lib/redis.rb', line 1430

def sdiffstore(destination, *keys)
  synchronize do |client|
    client.call([:sdiffstore, destination] + keys)
  end
end

#select(db) ⇒ String

Change the selected database for the current connection.

Parameters:

  • db (Fixnum)

    zero-based index of the DB to use (0 to 15)

Returns:

  • (String)

    OK


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# File 'lib/redis.rb', line 128

def select(db)
  synchronize do |client|
    client.db = db
    client.call([:select, db])
  end
end

#sentinel(subcommand, *args) ⇒ Array<String>, ...

Interact with the sentinel command (masters, master, slaves, failover)

Parameters:

  • subcommand (String)

    e.g. masters, master, slaves

  • args (Array<String>)

    depends on subcommand

Returns:

  • (Array<String>, Hash<String, String>, String)

    depends on subcommand


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# File 'lib/redis.rb', line 2706

def sentinel(subcommand, *args)
  subcommand = subcommand.to_s.downcase
  synchronize do |client|
    client.call([:sentinel, subcommand] + args) do |reply|
      case subcommand
      when "get-master-addr-by-name"
        reply
      else
        if reply.kind_of?(Array)
          if reply[0].kind_of?(Array)
            reply.map(&Hashify)
          else
            Hashify.call(reply)
          end
        else
          reply
        end
      end
    end
  end
end

#set(key, value, options = {}) ⇒ String, Boolean

Set the string value of a key.

Parameters:

  • key (String)
  • value (String)
  • options (Hash) (defaults to: {})
    • :ex => Fixnum: Set the specified expire time, in seconds.
    • :px => Fixnum: Set the specified expire time, in milliseconds.
    • :nx => true: Only set the key if it does not already exist.
    • :xx => true: Only set the key if it already exist.

Returns:

  • (String, Boolean)

    "OK" or true, false if :nx => true or :xx => true


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# File 'lib/redis.rb', line 752

def set(key, value, options = {})
  args = []

  ex = options[:ex]
  args.concat(["EX", ex]) if ex

  px = options[:px]
  args.concat(["PX", px]) if px

  nx = options[:nx]
  args.concat(["NX"]) if nx

  xx = options[:xx]
  args.concat(["XX"]) if xx

  synchronize do |client|
    if nx || xx
      client.call([:set, key, value.to_s] + args, &BoolifySet)
    else
      client.call([:set, key, value.to_s] + args)
    end
  end
end

#setbit(key, offset, value) ⇒ Fixnum

Sets or clears the bit at offset in the string value stored at key.

Parameters:

  • key (String)
  • offset (Fixnum)

    bit offset

  • value (Fixnum)

    bit value 0 or 1

Returns:

  • (Fixnum)

    the original bit value stored at offset


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# File 'lib/redis.rb', line 948

def setbit(key, offset, value)
  synchronize do |client|
    client.call([:setbit, key, offset, value])
  end
end

#setex(key, ttl, value) ⇒ String

Set the time to live in seconds of a key.

Parameters:

  • key (String)
  • ttl (Fixnum)
  • value (String)

Returns:

  • (String)

    "OK"


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# File 'lib/redis.rb', line 782

def setex(key, ttl, value)
  synchronize do |client|
    client.call([:setex, key, ttl, value.to_s])
  end
end

#setnx(key, value) ⇒ Boolean

Set the value of a key, only if the key does not exist.

Parameters:

  • key (String)
  • value (String)

Returns:

  • (Boolean)

    whether the key was set or not


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# File 'lib/redis.rb', line 805

def setnx(key, value)
  synchronize do |client|
    client.call([:setnx, key, value.to_s], &Boolify)
  end
end

#setrange(key, offset, value) ⇒ Fixnum

Overwrite part of a string at key starting at the specified offset.

Parameters:

  • key (String)
  • offset (Fixnum)

    byte offset

  • value (String)

Returns:

  • (Fixnum)

    length of the string after it was modified


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# File 'lib/redis.rb', line 923

def setrange(key, offset, value)
  synchronize do |client|
    client.call([:setrange, key, offset, value.to_s])
  end
end

#shutdownObject

Synchronously save the dataset to disk and then shut down the server.


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# File 'lib/redis.rb', line 313

def shutdown
  synchronize do |client|
    client.with_reconnect(false) do
      begin
        client.call([:shutdown])
      rescue ConnectionError
        # This means Redis has probably exited.
        nil
      end
    end
  end
end

#sinter(*keys) ⇒ Array<String>

Intersect multiple sets.

Parameters:

  • keys (String, Array<String>)

    keys pointing to sets to intersect

Returns:

  • (Array<String>)

    members in the intersection


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# File 'lib/redis.rb', line 1440

def sinter(*keys)
  synchronize do |client|
    client.call([:sinter] + keys)
  end
end

#sinterstore(destination, *keys) ⇒ Fixnum

Intersect multiple sets and store the resulting set in a key.

Parameters:

  • destination (String)

    destination key

  • keys (String, Array<String>)

    keys pointing to sets to intersect

Returns:

  • (Fixnum)

    number of elements in the resulting set


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# File 'lib/redis.rb', line 1451

def sinterstore(destination, *keys)
  synchronize do |client|
    client.call([:sinterstore, destination] + keys)
  end
end

#sismember(key, member) ⇒ Boolean

Determine if a given value is a member of a set.

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 1399

def sismember(key, member)
  synchronize do |client|
    client.call([:sismember, key, member], &Boolify)
  end
end

#slaveof(host, port) ⇒ Object

Make the server a slave of another instance, or promote it as master.


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# File 'lib/redis.rb', line 327

def slaveof(host, port)
  synchronize do |client|
    client.call([:slaveof, host, port])
  end
end

#slowlog(subcommand, length = nil) ⇒ Array<String>, ...

Interact with the slowlog (get, len, reset)

Parameters:

  • subcommand (String)

    e.g. get, len, reset

  • length (Fixnum) (defaults to: nil)

    maximum number of entries to return

Returns:

  • (Array<String>, Fixnum, String)

    depends on subcommand


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# File 'lib/redis.rb', line 338

def slowlog(subcommand, length=nil)
  synchronize do |client|
    args = [:slowlog, subcommand]
    args << length if length
    client.call args
  end
end

#smembers(key) ⇒ Array<String>

Get all the members in a set.

Parameters:

  • key (String)

Returns:

  • (Array<String>)

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# File 'lib/redis.rb', line 1409

def smembers(key)
  synchronize do |client|
    client.call([:smembers, key])
  end
end

#smove(source, destination, member) ⇒ Boolean

Move a member from one set to another.

Parameters:

  • source (String)

    source key

  • destination (String)

    destination key

  • member (String)

    member to move from source to destination

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 1388

def smove(source, destination, member)
  synchronize do |client|
    client.call([:smove, source, destination, member], &Boolify)
  end
end

#sort(key, options = {}) ⇒ Array<String>, ...

Sort the elements in a list, set or sorted set.

Examples:

Retrieve the first 2 elements from an alphabetically sorted "list"

redis.sort("list", :order => "alpha", :limit => [0, 2])
  # => ["a", "b"]

Store an alphabetically descending list in "target"

redis.sort("list", :order => "desc alpha", :store => "target")
  # => 26

Parameters:

  • key (String)
  • options (Hash) (defaults to: {})
    • :by => String: use external key to sort elements by
    • :limit => [offset, count]: skip offset elements, return a maximum of count elements
    • :get => [String, Array<String>]: single key or array of keys to retrieve per element in the result
    • :order => String: combination of ASC, DESC and optionally ALPHA
    • :store => String: key to store the result at

Returns:

  • (Array<String>, Array<Array<String>>, Fixnum)
    • when :get is not specified, or holds a single element, an array of elements
    • when :get is specified, and holds more than one element, an array of elements where every element is an array with the result for every element specified in :get
    • when :store is specified, the number of elements in the stored result

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# File 'lib/redis.rb', line 628

def sort(key, options = {})
  args = []

  by = options[:by]
  args.concat(["BY", by]) if by

  limit = options[:limit]
  args.concat(["LIMIT"] + limit) if limit

  get = Array(options[:get])
  args.concat(["GET"].product(get).flatten) unless get.empty?

  order = options[:order]
  args.concat(order.split(" ")) if order

  store = options[:store]
  args.concat(["STORE", store]) if store

  synchronize do |client|
    client.call([:sort, key] + args) do |reply|
      if get.size > 1 && !store
        if reply
          reply.each_slice(get.size).to_a
        end
      else
        reply
      end
    end
  end
end

#spop(key, count = nil) ⇒ String

Remove and return one or more random member from a set.

Parameters:

  • key (String)
  • count (Fixnum) (defaults to: nil)

Returns:

  • (String)

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# File 'lib/redis.rb', line 1357

def spop(key, count = nil)
  synchronize do |client|
    if count.nil?
      client.call([:spop, key])
    else
      client.call([:spop, key, count])
    end
  end
end

#srandmember(key, count = nil) ⇒ String

Get one or more random members from a set.

Parameters:

  • key (String)
  • count (Fixnum) (defaults to: nil)

Returns:

  • (String)

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# File 'lib/redis.rb', line 1372

def srandmember(key, count = nil)
  synchronize do |client|
    if count.nil?
      client.call([:srandmember, key])
    else
      client.call([:srandmember, key, count])
    end
  end
end

#srem(key, member) ⇒ Boolean, Fixnum

Remove one or more members from a set.

Parameters:

  • key (String)
  • member (String, Array<String>)

    one member, or array of members

Returns:

  • (Boolean, Fixnum)

    Boolean when a single member is specified, holding whether or not removing the member succeeded, or Fixnum when an array of members is specified, holding the number of members that were successfully removed


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# File 'lib/redis.rb', line 1338

def srem(key, member)
  synchronize do |client|
    client.call([:srem, key, member]) do |reply|
      if member.is_a? Array
        # Variadic: return integer
        reply
      else
        # Single argument: return boolean
        Boolify.call(reply)
      end
    end
  end
end

#sscan(key, cursor, options = {}) ⇒ String+

Scan a set

Examples:

Retrieve the first batch of keys in a set

redis.sscan("set", 0)

Parameters:

  • cursor (String, Integer)

    the cursor of the iteration

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (String, Array<String>)

    the next cursor and all found members


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# File 'lib/redis.rb', line 2640

def sscan(key, cursor, options={})
  _scan(:sscan, cursor, [key], options)
end

#sscan_each(key, options = {}, &block) ⇒ Enumerator

Scan a set

Examples:

Retrieve all of the keys in a set

redis.sscan_each("set").to_a
# => ["key1", "key2", "key3"]

Parameters:

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (Enumerator)

    an enumerator for all keys in the set


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# File 'lib/redis.rb', line 2655

def sscan_each(key, options={}, &block)
  return to_enum(:sscan_each, key, options) unless block_given?
  cursor = 0
  loop do
    cursor, keys = sscan(key, cursor, options)
    keys.each(&block)
    break if cursor == "0"
  end
end

#strlen(key) ⇒ Fixnum

Get the length of the value stored in a key.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    the length of the value stored in the key, or 0 if the key does not exist


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# File 'lib/redis.rb', line 1038

def strlen(key)
  synchronize do |client|
    client.call([:strlen, key])
  end
end

#subscribe(*channels, &block) ⇒ Object

Listen for messages published to the given channels.


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# File 'lib/redis.rb', line 2178

def subscribe(*channels, &block)
  synchronize do |client|
    _subscription(:subscribe, 0, channels, block)
  end
end

#subscribe_with_timeout(timeout, *channels, &block) ⇒ Object

Listen for messages published to the given channels. Throw a timeout error if there is no messages for a timeout period.


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# File 'lib/redis.rb', line 2185

def subscribe_with_timeout(timeout, *channels, &block)
  synchronize do |client|
    _subscription(:subscribe_with_timeout, timeout, channels, block)
  end
end

#subscribed?Boolean

Returns:

  • (Boolean)

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# File 'lib/redis.rb', line 2171

def subscribed?
  synchronize do |client|
    client.kind_of? SubscribedClient
  end
end

#sunion(*keys) ⇒ Array<String>

Add multiple sets.

Parameters:

  • keys (String, Array<String>)

    keys pointing to sets to unify

Returns:

  • (Array<String>)

    members in the union


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# File 'lib/redis.rb', line 1461

def sunion(*keys)
  synchronize do |client|
    client.call([:sunion] + keys)
  end
end

#sunionstore(destination, *keys) ⇒ Fixnum

Add multiple sets and store the resulting set in a key.

Parameters:

  • destination (String)

    destination key

  • keys (String, Array<String>)

    keys pointing to sets to unify

Returns:

  • (Fixnum)

    number of elements in the resulting set


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# File 'lib/redis.rb', line 1472

def sunionstore(destination, *keys)
  synchronize do |client|
    client.call([:sunionstore, destination] + keys)
  end
end

#syncObject

Internal command used for replication.


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# File 'lib/redis.rb', line 347

def sync
  synchronize do |client|
    client.call([:sync])
  end
end

#synchronizeObject


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# File 'lib/redis.rb', line 44

def synchronize
  mon_synchronize { yield(@client) }
end

#timeArray<Fixnum>

Return the server time.

Examples:

r.time # => [ 1333093196, 606806 ]

Returns:

  • (Array<Fixnum>)

    tuple of seconds since UNIX epoch and microseconds in the current second


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# File 'lib/redis.rb', line 360

def time
  synchronize do |client|
    client.call([:time]) do |reply|
      reply.map(&:to_i) if reply
    end
  end
end

#ttl(key) ⇒ Fixnum

Get the time to live (in seconds) for a key.

In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.

Starting with Redis 2.8 the return value in case of error changed:

- The command returns -2 if the key does not exist.
- The command returns -1 if the key exists but has no associated expire.

Parameters:

  • key (String)

Returns:

  • (Fixnum)

    remaining time to live in seconds.


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# File 'lib/redis.rb', line 412

def ttl(key)
  synchronize do |client|
    client.call([:ttl, key])
  end
end

#type(key) ⇒ String

Determine the type stored at key.

Parameters:

  • key (String)

Returns:

  • (String)

    string, list, set, zset, hash or none


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# File 'lib/redis.rb', line 663

def type(key)
  synchronize do |client|
    client.call([:type, key])
  end
end

#unsubscribe(*channels) ⇒ Object

Stop listening for messages posted to the given channels.


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# File 'lib/redis.rb', line 2192

def unsubscribe(*channels)
  synchronize do |client|
    raise RuntimeError, "Can't unsubscribe if not subscribed." unless subscribed?
    client.unsubscribe(*channels)
  end
end

#unwatchString

Forget about all watched keys.

Returns:

  • (String)

    OK

See Also:


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# File 'lib/redis.rb', line 2284

def unwatch
  synchronize do |client|
    client.call([:unwatch])
  end
end

#watch(*keys) ⇒ Object, String

Watch the given keys to determine execution of the MULTI/EXEC block.

Using a block is optional, but is necessary for thread-safety.

An #unwatch is automatically issued if an exception is raised within the block that is a subclass of StandardError and is not a ConnectionError.

Examples:

With a block

redis.watch("key") do
  if redis.get("key") == "some value"
    redis.multi do |multi|
      multi.set("key", "other value")
      multi.incr("counter")
    end
  else
    redis.unwatch
  end
end
  # => ["OK", 6]

Without a block

redis.watch("key")
  # => "OK"

Parameters:

  • keys (String, Array<String>)

    one or more keys to watch

Returns:

  • (Object)

    if using a block, returns the return value of the block

  • (String)

    if not using a block, returns OK

See Also:


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# File 'lib/redis.rb', line 2259

def watch(*keys)
  synchronize do |client|
    res = client.call([:watch] + keys)

    if block_given?
      begin
        yield(self)
      rescue ConnectionError
        raise
      rescue StandardError
        unwatch
        raise
      end
    else
      res
    end
  end
end

#with_reconnect(val = true, &blk) ⇒ Object

Run code with the client reconnecting


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# File 'lib/redis.rb', line 49

def with_reconnect(val=true, &blk)
  synchronize do |client|
    client.with_reconnect(val, &blk)
  end
end

#without_reconnect(&blk) ⇒ Object

Run code without the client reconnecting


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# File 'lib/redis.rb', line 56

def without_reconnect(&blk)
  with_reconnect(false, &blk)
end

#zadd(key, *args) ⇒ Boolean, ...

Add one or more members to a sorted set, or update the score for members that already exist.

Examples:

Add a single [score, member] pair to a sorted set

redis.zadd("zset", 32.0, "member")

Add an array of [score, member] pairs to a sorted set

redis.zadd("zset", [[32.0, "a"], [64.0, "b"]])

Parameters:

  • key (String)
  • args ([Float, String], Array<[Float, String]>)
    • a single [score, member] pair
    • an array of [score, member] pairs
  • options (Hash)
    • :xx => true: Only update elements that already exist (never add elements)
    • :nx => true: Don't update already existing elements (always add new elements)
    • :ch => true: Modify the return value from the number of new elements added, to the total number of elements changed (CH is an abbreviation of changed); changed elements are new elements added and elements already existing for which the score was updated
    • :incr => true: When this option is specified ZADD acts like ZINCRBY; only one score-element pair can be specified in this mode

Returns:

  • (Boolean, Fixnum, Float)
    • Boolean when a single pair is specified, holding whether or not it was added to the sorted set.
    • Fixnum when an array of pairs is specified, holding the number of pairs that were added to the sorted set.
    • Float when option :incr is specified, holding the score of the member after incrementing it.

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# File 'lib/redis.rb', line 1523

def zadd(key, *args) #, options
  zadd_options = []
  if args.last.is_a?(Hash)
    options = args.pop

    nx = options[:nx]
    zadd_options << "NX" if nx

    xx = options[:xx]
    zadd_options << "XX" if xx

    ch = options[:ch]
    zadd_options << "CH" if ch

    incr = options[:incr]
    zadd_options << "INCR" if incr
  end

  synchronize do |client|
    if args.size == 1 && args[0].is_a?(Array)
      # Variadic: return float if INCR, integer if !INCR
      client.call([:zadd, key] + zadd_options + args[0], &(incr ? Floatify : nil))
    elsif args.size == 2
      # Single pair: return float if INCR, boolean if !INCR
      client.call([:zadd, key] + zadd_options + args, &(incr ? Floatify : Boolify))
    else
      raise ArgumentError, "wrong number of arguments"
    end
  end
end

#zcard(key) ⇒ Fixnum

Get the number of members in a sorted set.

Examples:

redis.zcard("zset")
  # => 4

Parameters:

  • key (String)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 1486

def zcard(key)
  synchronize do |client|
    client.call([:zcard, key])
  end
end

#zcount(key, min, max) ⇒ Fixnum

Count the members in a sorted set with scores within the given values.

Examples:

Count members with score >= 5 and < 100

redis.zcount("zset", "5", "(100")
  # => 2

Count members with scores > 5

redis.zcount("zset", "(5", "+inf")
  # => 2

Parameters:

  • key (String)
  • min (String)
    • inclusive minimum score is specified verbatim
    • exclusive minimum score is specified by prefixing (
  • max (String)
    • inclusive maximum score is specified verbatim
    • exclusive maximum score is specified by prefixing (

Returns:

  • (Fixnum)

    number of members in within the specified range


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# File 'lib/redis.rb', line 1912

def zcount(key, min, max)
  synchronize do |client|
    client.call([:zcount, key, min, max])
  end
end

#zincrby(key, increment, member) ⇒ Float

Increment the score of a member in a sorted set.

Examples:

redis.zincrby("zset", 32.0, "a")
  # => 64.0

Parameters:

  • key (String)
  • increment (Float)
  • member (String)

Returns:

  • (Float)

    score of the member after incrementing it


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# File 'lib/redis.rb', line 1564

def zincrby(key, increment, member)
  synchronize do |client|
    client.call([:zincrby, key, increment, member], &Floatify)
  end
end

#zinterstore(destination, keys, options = {}) ⇒ Fixnum

Intersect multiple sorted sets and store the resulting sorted set in a new key.

Examples:

Compute the intersection of 2*zsetA with 1*zsetB, summing their scores

redis.zinterstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum")
  # => 4

Parameters:

  • destination (String)

    destination key

  • keys (Array<String>)

    source keys

  • options (Hash) (defaults to: {})
    • :weights => [Float, Float, ...]: weights to associate with source sorted sets
    • :aggregate => String: aggregate function to use (sum, min, max, ...)

Returns:

  • (Fixnum)

    number of elements in the resulting sorted set


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# File 'lib/redis.rb', line 1932

def zinterstore(destination, keys, options = {})
  args = []

  weights = options[:weights]
  args.concat(["WEIGHTS"] + weights) if weights

  aggregate = options[:aggregate]
  args.concat(["AGGREGATE", aggregate]) if aggregate

  synchronize do |client|
    client.call([:zinterstore, destination, keys.size] + keys + args)
  end
end

#zlexcount(key, min, max) ⇒ Fixnum

Count the members, with the same score in a sorted set, within the given lexicographical range.

Examples:

Count members matching a

redis.zlexcount("zset", "[a", "[a\xff")
  # => 1

Count members matching a-z

redis.zlexcount("zset", "[a", "[z\xff")
  # => 26

Parameters:

  • key (String)
  • min (String)
    • inclusive minimum is specified by prefixing (
    • exclusive minimum is specified by prefixing [
  • max (String)
    • inclusive maximum is specified by prefixing (
    • exclusive maximum is specified by prefixing [

Returns:

  • (Fixnum)

    number of members within the specified lexicographical range


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# File 'lib/redis.rb', line 1735

def zlexcount(key, min, max)
  synchronize do |client|
    client.call([:zlexcount, key, min, max])
  end
end

#zrange(key, start, stop, options = {}) ⇒ Array<String>, Array<[String, Float]>

Return a range of members in a sorted set, by index.

Examples:

Retrieve all members from a sorted set

redis.zrange("zset", 0, -1)
  # => ["a", "b"]

Retrieve all members and their scores from a sorted set

redis.zrange("zset", 0, -1, :with_scores => true)
  # => [["a", 32.0], ["b", 64.0]]

Parameters:

  • key (String)
  • start (Fixnum)

    start index

  • stop (Fixnum)

    stop index

  • options (Hash) (defaults to: {})
    • :with_scores => true: include scores in output

Returns:

  • (Array<String>, Array<[String, Float]>)
    • when :with_scores is not specified, an array of members
    • when :with_scores is specified, an array with [member, score] pairs

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# File 'lib/redis.rb', line 1634

def zrange(key, start, stop, options = {})
  args = []

  with_scores = options[:with_scores] || options[:withscores]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  synchronize do |client|
    client.call([:zrange, key, start, stop] + args, &block)
  end
end

#zrangebylex(key, min, max, options = {}) ⇒ Array<String>, Array<[String, Float]>

Return a range of members with the same score in a sorted set, by lexicographical ordering

Examples:

Retrieve members matching a

redis.zrangebylex("zset", "[a", "[a\xff")
  # => ["aaren", "aarika", "abagael", "abby"]

Retrieve the first 2 members matching a

redis.zrangebylex("zset", "[a", "[a\xff", :limit => [0, 2])
  # => ["aaren", "aarika"]

Parameters:

  • key (String)
  • min (String)
    • inclusive minimum is specified by prefixing (
    • exclusive minimum is specified by prefixing [
  • max (String)
    • inclusive maximum is specified by prefixing (
    • exclusive maximum is specified by prefixing [
  • options (Hash) (defaults to: {})
    • :limit => [offset, count]: skip offset members, return a maximum of count members

Returns:

  • (Array<String>, Array<[String, Float]>)

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# File 'lib/redis.rb', line 1762

def zrangebylex(key, min, max, options = {})
  args = []

  limit = options[:limit]
  args.concat(["LIMIT"] + limit) if limit

  synchronize do |client|
    client.call([:zrangebylex, key, min, max] + args)
  end
end

#zrangebyscore(key, min, max, options = {}) ⇒ Array<String>, Array<[String, Float]>

Return a range of members in a sorted set, by score.

Examples:

Retrieve members with score >= 5 and < 100

redis.zrangebyscore("zset", "5", "(100")
  # => ["a", "b"]

Retrieve the first 2 members with score >= 0

redis.zrangebyscore("zset", "0", "+inf", :limit => [0, 2])
  # => ["a", "b"]

Retrieve members and their scores with scores > 5

redis.zrangebyscore("zset", "(5", "+inf", :with_scores => true)
  # => [["a", 32.0], ["b", 64.0]]

Parameters:

  • key (String)
  • min (String)
    • inclusive minimum score is specified verbatim
    • exclusive minimum score is specified by prefixing (
  • max (String)
    • inclusive maximum score is specified verbatim
    • exclusive maximum score is specified by prefixing (
  • options (Hash) (defaults to: {})
    • :with_scores => true: include scores in output
    • :limit => [offset, count]: skip offset members, return a maximum of count members

Returns:

  • (Array<String>, Array<[String, Float]>)
    • when :with_scores is not specified, an array of members
    • when :with_scores is specified, an array with [member, score] pairs

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# File 'lib/redis.rb', line 1822

def zrangebyscore(key, min, max, options = {})
  args = []

  with_scores = options[:with_scores] || options[:withscores]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  limit = options[:limit]
  args.concat(["LIMIT"] + limit) if limit

  synchronize do |client|
    client.call([:zrangebyscore, key, min, max] + args, &block)
  end
end

#zrank(key, member) ⇒ Fixnum

Determine the index of a member in a sorted set.

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 1680

def zrank(key, member)
  synchronize do |client|
    client.call([:zrank, key, member])
  end
end

#zrem(key, member) ⇒ Boolean, Fixnum

Remove one or more members from a sorted set.

Examples:

Remove a single member from a sorted set

redis.zrem("zset", "a")

Remove an array of members from a sorted set

redis.zrem("zset", ["a", "b"])

Parameters:

  • key (String)
  • member (String, Array<String>)
    • a single member
    • an array of members

Returns:

  • (Boolean, Fixnum)
    • Boolean when a single member is specified, holding whether or not it was removed from the sorted set
    • Fixnum when an array of pairs is specified, holding the number of members that were removed to the sorted set

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# File 'lib/redis.rb', line 1587

def zrem(key, member)
  synchronize do |client|
    client.call([:zrem, key, member]) do |reply|
      if member.is_a? Array
        # Variadic: return integer
        reply
      else
        # Single argument: return boolean
        Boolify.call(reply)
      end
    end
  end
end

#zremrangebyrank(key, start, stop) ⇒ Fixnum

Remove all members in a sorted set within the given indexes.

Examples:

Remove first 5 members

redis.zremrangebyrank("zset", 0, 4)
  # => 5

Remove last 5 members

redis.zremrangebyrank("zset", -5, -1)
  # => 5

Parameters:

  • key (String)
  • start (Fixnum)

    start index

  • stop (Fixnum)

    stop index

Returns:

  • (Fixnum)

    number of members that were removed


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# File 'lib/redis.rb', line 1711

def zremrangebyrank(key, start, stop)
  synchronize do |client|
    client.call([:zremrangebyrank, key, start, stop])
  end
end

#zremrangebyscore(key, min, max) ⇒ Fixnum

Remove all members in a sorted set within the given scores.

Examples:

Remove members with score >= 5 and < 100

redis.zremrangebyscore("zset", "5", "(100")
  # => 2

Remove members with scores > 5

redis.zremrangebyscore("zset", "(5", "+inf")
  # => 2

Parameters:

  • key (String)
  • min (String)
    • inclusive minimum score is specified verbatim
    • exclusive minimum score is specified by prefixing (
  • max (String)
    • inclusive maximum score is specified verbatim
    • exclusive maximum score is specified by prefixing (

Returns:

  • (Fixnum)

    number of members that were removed


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# File 'lib/redis.rb', line 1889

def zremrangebyscore(key, min, max)
  synchronize do |client|
    client.call([:zremrangebyscore, key, min, max])
  end
end

#zrevrange(key, start, stop, options = {}) ⇒ Object

Return a range of members in a sorted set, by index, with scores ordered from high to low.

Examples:

Retrieve all members from a sorted set

redis.zrevrange("zset", 0, -1)
  # => ["b", "a"]

Retrieve all members and their scores from a sorted set

redis.zrevrange("zset", 0, -1, :with_scores => true)
  # => [["b", 64.0], ["a", 32.0]]

See Also:


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# File 'lib/redis.rb', line 1660

def zrevrange(key, start, stop, options = {})
  args = []

  with_scores = options[:with_scores] || options[:withscores]

  if with_scores
    args << "WITHSCORES"
    block = FloatifyPairs
  end

  synchronize do |client|
    client.call([:zrevrange, key, start, stop] + args, &block)
  end
end

#zrevrangebylex(key, max, min, options = {}) ⇒ Object

Return a range of members with the same score in a sorted set, by reversed lexicographical ordering. Apart from the reversed ordering, #zrevrangebylex is similar to #zrangebylex.

Examples:

Retrieve members matching a

redis.zrevrangebylex("zset", "[a", "[a\xff")
  # => ["abbygail", "abby", "abagael", "aaren"]

Retrieve the last 2 members matching a

redis.zrevrangebylex("zset", "[a", "[a\xff", :limit => [0, 2])
  # => ["abbygail", "abby"]

See Also:


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# File 'lib/redis.rb', line 1784

def zrevrangebylex(key, max, min, options = {})
  args = []

  limit = options[:limit]
  args.concat(["LIMIT"] + limit) if limit

  synchronize do |client|
    client.call([:zrevrangebylex, key, max, min] + args)
  end
end

#zrevrangebyscore(key, max, min, options = {}) ⇒ Object

Return a range of members in a sorted set, by score, with scores ordered from high to low.

Examples:

Retrieve members with score < 100 and >= 5

redis.zrevrangebyscore("zset", "(100", "5")
  # => ["b", "a"]

Retrieve the first 2 members with score <= 0

redis.zrevrangebyscore("zset", "0", "-inf", :limit => [0, 2])
  # => ["b", "a"]

Retrieve members and their scores with scores > 5

redis.zrevrangebyscore("zset", "+inf", "(5", :with_scores => true)
  # => [["b", 64.0], ["a", 32.0]]

See Also:


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# File 'lib/redis.rb', line 1854

def zrevrangebyscore(key, max, min, options = {})
  args = []

  with_scores = options[:with_scores] || options[:withscores]

  if with_scores
    args << ["WITHSCORES"]
    block = FloatifyPairs
  end

  limit = options[:limit]
  args.concat(["LIMIT"] + limit) if limit

  synchronize do |client|
    client.call([:zrevrangebyscore, key, max, min] + args, &block)
  end
end

#zrevrank(key, member) ⇒ Fixnum

Determine the index of a member in a sorted set, with scores ordered from high to low.

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Fixnum)

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# File 'lib/redis.rb', line 1692

def zrevrank(key, member)
  synchronize do |client|
    client.call([:zrevrank, key, member])
  end
end

#zscan(key, cursor, options = {}) ⇒ String, Array<[String, Float]>

Scan a sorted set

Examples:

Retrieve the first batch of key/value pairs in a hash

redis.zscan("zset", 0)

Parameters:

  • cursor (String, Integer)

    the cursor of the iteration

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (String, Array<[String, Float]>)

    the next cursor and all found members and scores


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# File 'lib/redis.rb', line 2602

def zscan(key, cursor, options={})
  _scan(:zscan, cursor, [key], options) do |reply|
    [reply[0], FloatifyPairs.call(reply[1])]
  end
end

#zscan_each(key, options = {}, &block) ⇒ Enumerator

Scan a sorted set

Examples:

Retrieve all of the members/scores in a sorted set

redis.zscan_each("zset").to_a
# => [["key70", "70"], ["key80", "80"]]

Parameters:

  • options (Hash) (defaults to: {})
    • :match => String: only return keys matching the pattern
    • :count => Integer: return count keys at most per iteration

Returns:

  • (Enumerator)

    an enumerator for all found scores and members


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# File 'lib/redis.rb', line 2619

def zscan_each(key, options={}, &block)
  return to_enum(:zscan_each, key, options) unless block_given?
  cursor = 0
  loop do
    cursor, values = zscan(key, cursor, options)
    values.each(&block)
    break if cursor == "0"
  end
end

#zscore(key, member) ⇒ Float

Get the score associated with the given member in a sorted set.

Examples:

Get the score for member "a"

redis.zscore("zset", "a")
  # => 32.0

Parameters:

  • key (String)
  • member (String)

Returns:

  • (Float)

    score of the member


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# File 'lib/redis.rb', line 1610

def zscore(key, member)
  synchronize do |client|
    client.call([:zscore, key, member], &Floatify)
  end
end

#zunionstore(destination, keys, options = {}) ⇒ Fixnum

Add multiple sorted sets and store the resulting sorted set in a new key.

Examples:

Compute the union of 2*zsetA with 1*zsetB, summing their scores

redis.zunionstore("zsetC", ["zsetA", "zsetB"], :weights => [2.0, 1.0], :aggregate => "sum")
  # => 8

Parameters:

  • destination (String)

    destination key

  • keys (Array<String>)

    source keys

  • options (Hash) (defaults to: {})
    • :weights => [Float, Float, ...]: weights to associate with source sorted sets
    • :aggregate => String: aggregate function to use (sum, min, max, ...)

Returns:

  • (Fixnum)

    number of elements in the resulting sorted set


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# File 'lib/redis.rb', line 1959

def zunionstore(destination, keys, options = {})
  args = []

  weights = options[:weights]
  args.concat(["WEIGHTS"] + weights) if weights

  aggregate = options[:aggregate]
  args.concat(["AGGREGATE", aggregate]) if aggregate

  synchronize do |client|
    client.call([:zunionstore, destination, keys.size] + keys + args)
  end
end