Class: Redis::NativeHash

Inherits:
TrackedHash show all
Includes:
ClientHelper, KeyHelper
Defined in:
lib/redis/native_hash.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from KeyHelper

#convert_key, #generate_key, #key, #redis_key

Methods included from ClientHelper

included

Methods inherited from TrackedHash

#added, #changed, #deleted, #dup, #original, #populate, #retrack, #untrack

Methods inherited from Hash

#stringify_keys!

Constructor Details

#initialize(aargh = nil) ⇒ NativeHash

Returns a new instance of NativeHash.



12
13
14
15
16
17
18
19
20
21
22
 
# File 'lib/redis/native_hash.rb', line 12

def initialize(aargh = nil)
  super(nil)
  case aargh
  when String,Symbol
    self.namespace = aargh
  when Hash
    self.namespace = aargh.keys.first
    self.key       = aargh.values.first
  end
  track!
end

Instance Attribute Details

#namespace ⇒ Object

Returns the value of attribute namespace.



10
11
12
 
# File 'lib/redis/native_hash.rb', line 10

def namespace
  @namespace
end

#version ⇒ Object 



57
58
59
 
# File 'lib/redis/native_hash.rb', line 57

def version
  @version ||= generate_key
end

Class Method Details

.attr_persist(*attributes) ⇒ Object 



175
176
177
178
179
180
181
182
183
184
185
186
187
 
# File 'lib/redis/native_hash.rb', line 175

def attr_persist(*attributes)
  attributes.each do |attr|
    class_eval <<-EOS
      def #{attr}=(value)
        self["#{attr}"] = value
      end

      def #{attr}
        self["#{attr}"]
      end
    EOS
  end
end

.build(namespace, key, values) ⇒ Object 



162
163
164
165
166
167
168
 
# File 'lib/redis/native_hash.rb', line 162

def build(namespace, key, values)
  h = self.new
  h.namespace = namespace
  h.key = key
  h.populate(values)
  h
end

.fetch_values(key) ⇒ Object 



170
171
172
173
 
# File 'lib/redis/native_hash.rb', line 170

def fetch_values(key)
  results = redis.hgetall(key)
  results.each_pair { |key,value| results[key] = Redis::Marshal.load(value) }
end

.find(params) ⇒ Object 



135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
 
# File 'lib/redis/native_hash.rb', line 135

def find(params)
  case params
  when Hash
    hashes = []
    params.each_pair do |namespace, key|
      result = fetch_values( "#{namespace}:#{key}" )
      unless result.empty?
        hashes << build(namespace,key,result)
      end
    end
    unless hashes.empty?
      hashes.size == 1 ? hashes.first : hashes
    else
      nil
    end
  when String,Symbol
    unless self == Redis::NativeHash
      namespace = self.new.namespace.to_s
      namespace = "#{namespace}:" unless namespace.empty?
      result = fetch_values( "#{namespace}#{params}" )
    else
      result = fetch_values(params)
    end
    result.empty? ? nil : build(nil,params,result)
  end
end

Instance Method Details

#[](key) ⇒ Object 



33
34
35
 
# File 'lib/redis/native_hash.rb', line 33

def [](key)
   super convert_key(key)
end

#[]=(key, value) ⇒ Object Also known as: store 



24
25
26
 
# File 'lib/redis/native_hash.rb', line 24

def []=(key, value)
  super(convert_key(key), value)
end

#delete(key) ⇒ Object 



44
45
46
 
# File 'lib/redis/native_hash.rb', line 44

def delete(key)
  super convert_key(key)
end

#destroy ⇒ Object 



114
115
116
117
118
119
 
# File 'lib/redis/native_hash.rb', line 114

def destroy
  redis.del( redis_key )
  untrack!
  clear
  self.key = nil
end

#expire(seconds) ⇒ Object 



130
131
132
 
# File 'lib/redis/native_hash.rb', line 130

def expire(seconds)
  redis.expire(redis_key, seconds)
end

#fetch(key, *extras) ⇒ Object 



29
30
31
 
# File 'lib/redis/native_hash.rb', line 29

def fetch(key, *extras)
  super(convert_key(key),*extras)
end

#key=(new_key) ⇒ Object 



52
53
54
 
# File 'lib/redis/native_hash.rb', line 52

def key=(new_key)
  renew_key(new_key)
end

#key?(key) ⇒ Boolean Also known as: include?, has_key?, member?

Returns:

  • (Boolean) 


37
38
39
 
# File 'lib/redis/native_hash.rb', line 37

def key?(key)
  super convert_key(key)
end

#reload! ⇒ Object Also known as: reload 



108
109
110
111
 
# File 'lib/redis/native_hash.rb', line 108

def reload!
  hash = self.class.find( namespace ? {namespace => key} : key )
  self.update( hash ) if hash
end

#renew_key(new_key = nil) ⇒ Object 



121
122
123
124
125
126
127
128
 
# File 'lib/redis/native_hash.rb', line 121

def renew_key(new_key = nil)
  unless @key.nil? || @key == new_key
    redis.del( redis_key )
    original.clear
  end
  @key = new_key
  key
end

#replace(other_hash) ⇒ Object 



103
104
105
106
 
# File 'lib/redis/native_hash.rb', line 103

def replace(other_hash)
  clear
  update(other_hash)
end

#save(max_attempts = 5) ⇒ Object 



61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/redis/native_hash.rb', line 61

def save( max_attempts = 5 )
  (1..max_attempts).each do |n|
    redis.watch redis_key
    latest_version = redis.hget(redis_key, "__version")
    reload! unless ( latest_version.nil? || latest_version == self.version )
    self.version = nil # generate new version token
    changed_keys = (self.changed + self.added).uniq
    changes = []
    changed_keys.each do |key|
      changes.push( key, Redis::Marshal.dump(self[key]) )
    end
    deleted_keys = self.deleted
    if deleted_keys.empty? and changes.empty?
      redis.unwatch
      return true
    end
    success = redis.multi do
      redis.hmset( redis_key, *changes.push("__version", self.version) ) unless changes.empty?
      deleted_keys.each { |key| redis.hdel( redis_key, key) }
    end
    if success
      untrack!; track! #reset hash
      return true
    end
  end
  raise "Unable to save hash after max attempts (#{max_attempts}). " +
        "Amazing concurrency event may be underway. " +
        "Make some popcorn."
  false
end

#update(data) ⇒ Object 



92
93
94
95
96
97
98
99
100
101
 
# File 'lib/redis/native_hash.rb', line 92

def update(data)
  v = case data
    when self.class
      data.version
    when ::Hash
      data.delete("__version")
    end
  self.version = v unless v.nil?
  super(data.stringify_keys!)
end

#values_at(*indices) ⇒ Object 



48
49
50
 
# File 'lib/redis/native_hash.rb', line 48

def values_at(*indices)
  indices.collect { |key| self[ convert_key(key) ] }
end