Module: Capistrano::Configuration::Extensions::Actions::Invocation

Included in:
Capistrano::Configuration
Defined in:
lib/capistrano/configuration/extensions/actions/invocation.rb

Defined Under Namespace

Classes: BlockProxy

Instance Method Summary collapse

Instance Method Details

#parallelize(thread_count = nil) {|proxy| ... } ⇒ Object

Yields:

  • (proxy) 


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# File 'lib/capistrano/configuration/extensions/actions/invocation.rb', line 19

def parallelize(thread_count = nil)
  set :parallelize_thread_count, 10 unless respond_to?(:parallelize_thread_count)
        
  proxy = BlockProxy.new
  yield proxy
        
  logger.info "Running #{proxy.blocks.size} threads in chunks of #{thread_count || parallelize_thread_count}"
  run_parallelize_loop(proxy, thread_count || parallelize_thread_count)
end

#rollback_all_threads(threads) ⇒ Object 



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# File 'lib/capistrano/configuration/extensions/actions/invocation.rb', line 69

def rollback_all_threads(threads)
  Thread.new do
    threads.select {|t| !t[:rolled_back]}.each do |thread|
      Thread.current[:rollback_requests] = thread[:rollback_requests]
      rollback!
    end
  end.join
  rollback! # Rolling back main thread too
  true
end

#run_in_threads(blocks) ⇒ Object 



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# File 'lib/capistrano/configuration/extensions/actions/invocation.rb', line 43

def run_in_threads(blocks)
  blocks.collect do |blk|
    thread = Thread.new do
      logger.info "Running block in background thread"
      blk.call
    end
    begin
      thread.run
    rescue ThreadError
      thread[:exception_raised] = $!
    end
    thread
  end
end

#run_parallelize_loop(proxy, thread_count) ⇒ Object 



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# File 'lib/capistrano/configuration/extensions/actions/invocation.rb', line 29

def run_parallelize_loop(proxy, thread_count)
  batch = 1
  all_threads = []
  proxy.blocks.each_slice(thread_count) do |chunk|
    logger.info "Running batch number #{batch}"
    threads = run_in_threads(chunk)
    all_threads << threads
    wait_for(threads)
    rollback_all_threads(all_threads.flatten) and return if threads.any? {|t| t[:rolled_back] || t[:exception_raised]}
    batch += 1
  end
  all_threads
end

#wait_for(threads) ⇒ Object 



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# File 'lib/capistrano/configuration/extensions/actions/invocation.rb', line 58

def wait_for(threads)
  threads.each do |thread|
    begin
      thread.join
    rescue
      logger.important "Subthread failed: #{$!.message}"
      thread[:exception_raised] = $!
    end
  end
end