Module: Oxblood::Commands::Transactions

Included in:
Oxblood::Commands
Defined in:
lib/oxblood/commands/transactions.rb

Overview

See Also:

Instance Method Summary collapse

Instance Method Details

#discard ⇒ String, RError

Discard all commands issued after MULTI

Returns:

  • (String) —

    ‘OK’

  • (RError) —

    if called without transaction started

See Also:



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# File 'lib/oxblood/commands/transactions.rb', line 51

def discard
  run(:DISCARD).tap { connection.transaction_mode = false }
end

#exec ⇒ Array?

Execute all commands issued after MULTI

Returns:

  • (Array) —

    each element being the reply to each of the commands in the atomic transaction

  • (nil) —

    when WATCH was used and execution was aborted

See Also:



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# File 'lib/oxblood/commands/transactions.rb', line 42

def exec
  run(:EXEC).tap { connection.transaction_mode = false }
end

#multi ⇒ String, RError

Mark the start of a transaction block

Examples:

#exec will be executed automatically at the end of a block.

session.multi do
  session.ping
  session.ping
end
# => ['PONG', 'PONG']

Blockless variant.

session.multi
session.incr(:counter0)
session.incr(:counter1)
session.exec

Returns:

  • (String) —

    ‘OK’

  • (RError) —

    if multi called inside transaction

See Also:



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# File 'lib/oxblood/commands/transactions.rb', line 23

def multi
  response = run(:MULTI).tap do |resp|
    connection.transaction_mode = true if resp == 'OK'
  end

  if block_given?
    yield
    exec
  else
    response
  end
end

#unwatch ⇒ String

Forget about all watched keys

Returns:

  • (String) —

    ‘OK’

See Also:



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# File 'lib/oxblood/commands/transactions.rb', line 74

def unwatch
  run(:UNWATCH)
end

#watch(*keys) ⇒ String

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

Examples:

session.set(:cnt, 0)
session.watch(:cnt)
value = session.get(:cnt).to_i
value += 1
session.multi { session.set(:cnt, value) }
# => `['OK']` or `nil` if `cnt` was modified while was watched

Returns:

  • (String) —

    ‘OK’

See Also:



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# File 'lib/oxblood/commands/transactions.rb', line 66

def watch(*keys)
  run(:WATCH, keys)
end