module Resque

Constants

DEFAULT_HEARTBEAT_INTERVAL
DEFAULT_PRUNE_INTERVAL
Version

Attributes

enqueue_front[W]

By default, jobs are pushed to the back of the queue and popped from the front, resulting in “first in, first out” (FIFO) execution order. Set to true to push jobs to the front of the queue instead, resulting in “last in, first out” (LIFO) execution order.

heartbeat_interval[W]

Defines how often a Resque worker updates the heartbeat key. Must be less than the prune interval.

inline[RW]
inline?[RW]
logger[RW]

Set or retrieve the current logger object

prune_interval[W]

Defines how often Resque checks for dead workers.

Public Instance Methods

after_fork(&block) click to toggle source

The `after_fork` hook will be run in the child process and is passed the current job. Any changes you make, therefore, will only live as long as the job currently being processed.

Call with a block to register a hook. Call with no arguments to return all registered hooks.

# File lib/resque.rb, line 261
def after_fork(&block)
  block ? register_hook(:after_fork, block) : hooks(:after_fork)
end
after_fork=(block) click to toggle source

Register an after_fork proc.

# File lib/resque.rb, line 266
def after_fork=(block)
  register_hook(:after_fork, block)
end
after_pause(&block) click to toggle source

The `after_pause` hook will be run in the parent process after the worker has paused (via SIGCONT).

# File lib/resque.rb, line 283
def after_pause(&block)
  block ? register_hook(:after_pause, block) : hooks(:after_pause)
end
after_pause=(block) click to toggle source

Register an after_pause proc.

# File lib/resque.rb, line 288
def after_pause=(block)
  register_hook(:after_pause, block)
end
before_first_fork(&block) click to toggle source

The `before_first_fork` hook will be run in the parent process only once, before forking to run the first job. Be careful- any changes you make will be permanent for the lifespan of the worker.

Call with a block to register a hook. Call with no arguments to return all registered hooks.

# File lib/resque.rb, line 231
def before_first_fork(&block)
  block ? register_hook(:before_first_fork, block) : hooks(:before_first_fork)
end
before_first_fork=(block) click to toggle source

Register a before_first_fork proc.

# File lib/resque.rb, line 236
def before_first_fork=(block)
  register_hook(:before_first_fork, block)
end
before_fork(&block) click to toggle source

The `before_fork` hook will be run in the parent process before every job, so be careful- any changes you make will be permanent for the lifespan of the worker.

Call with a block to register a hook. Call with no arguments to return all registered hooks.

# File lib/resque.rb, line 246
def before_fork(&block)
  block ? register_hook(:before_fork, block) : hooks(:before_fork)
end
before_fork=(block) click to toggle source

Register a before_fork proc.

# File lib/resque.rb, line 251
def before_fork=(block)
  register_hook(:before_fork, block)
end
before_pause(&block) click to toggle source

The `before_pause` hook will be run in the parent process before the worker has paused processing (via pause_processing or SIGUSR2).

# File lib/resque.rb, line 272
def before_pause(&block)
  block ? register_hook(:before_pause, block) : hooks(:before_pause)
end
before_pause=(block) click to toggle source

Register a before_pause proc.

# File lib/resque.rb, line 277
def before_pause=(block)
  register_hook(:before_pause, block)
end
classify(dashed_word) click to toggle source

Given a word with dashes, returns a camel cased version of it.

classify('job-name') # => 'JobName'

# File lib/resque.rb, line 60
def classify(dashed_word)
  dashed_word.split('-').map(&:capitalize).join
end
constantize(camel_cased_word) click to toggle source

Tries to find a constant with the name specified in the argument string:

constantize(“Module”) # => Module constantize(“Test::Unit”) # => Test::Unit

The name is assumed to be the one of a top-level constant, no matter whether it starts with “::” or not. No lexical context is taken into account:

C = 'outside' module M

C = 'inside'
C # => 'inside'
constantize("C") # => 'outside', same as ::C

end

NameError is raised when the constant is unknown.

# File lib/resque.rb, line 81
def constantize(camel_cased_word)
  camel_cased_word = camel_cased_word.to_s

  if camel_cased_word.include?('-')
    camel_cased_word = classify(camel_cased_word)
  end

  names = camel_cased_word.split('::')
  names.shift if names.empty? || names.first.empty?

  constant = Object
  names.each do |name|
    args = Module.method(:const_get).arity != 1 ? [false] : []

    if constant.const_defined?(name, *args)
      constant = constant.const_get(name)
    else
      constant = constant.const_missing(name)
    end
  end
  constant
end
data_store()
Alias for: redis
decode(object) click to toggle source

Given a string, returns a Ruby object.

# File lib/resque.rb, line 43
def decode(object)
  return unless object

  begin
    if MultiJson.respond_to?(:dump) && MultiJson.respond_to?(:load)
      MultiJson.load object
    else
      MultiJson.decode object
    end
  rescue ::MultiJson::DecodeError => e
    raise Helpers::DecodeException, e.message, e.backtrace
  end
end
dequeue(klass, *args) click to toggle source

This method can be used to conveniently remove a job from a queue. It assumes the class you're passing it is a real Ruby class (not a string or reference) which either:

a) has a @queue ivar set
b) responds to `queue`

If either of those conditions are met, it will use the value obtained from performing one of the above operations to determine the queue.

If no queue can be inferred this method will raise a `Resque::NoQueueError`

If no args are given, this method will dequeue all jobs matching the provided class. See `Resque::Job.destroy` for more information.

Returns the number of jobs destroyed.

Example:

# Removes all jobs of class `UpdateNetworkGraph`
Resque.dequeue(GitHub::Jobs::UpdateNetworkGraph)

# Removes all jobs of class `UpdateNetworkGraph` with matching args.
Resque.dequeue(GitHub::Jobs::UpdateNetworkGraph, 'repo:135325')

This method is considered part of the `stable` API.

# File lib/resque.rb, line 488
def dequeue(klass, *args)
  # Perform before_dequeue hooks. Don't perform dequeue if any hook returns false
  before_hooks = Plugin.before_dequeue_hooks(klass).collect do |hook|
    klass.send(hook, *args)
  end
  return if before_hooks.any? { |result| result == false }

  destroyed = Job.destroy(queue_from_class(klass), klass, *args)

  Plugin.after_dequeue_hooks(klass).each do |hook|
    klass.send(hook, *args)
  end

  destroyed
end
encode(object) click to toggle source

Given a Ruby object, returns a string suitable for storage in a queue.

# File lib/resque.rb, line 34
def encode(object)
  if MultiJson.respond_to?(:dump) && MultiJson.respond_to?(:load)
    MultiJson.dump object
  else
    MultiJson.encode object
  end
end
enqueue(klass, *args) click to toggle source

This method can be used to conveniently add a job to a queue. It assumes the class you're passing it is a real Ruby class (not a string or reference) which either:

a) has a @queue ivar set
b) responds to `queue`

If either of those conditions are met, it will use the value obtained from performing one of the above operations to determine the queue.

If no queue can be inferred this method will raise a `Resque::NoQueueError`

Returns true if the job was queued, nil if the job was rejected by a before_enqueue hook.

This method is considered part of the `stable` API.

# File lib/resque.rb, line 432
def enqueue(klass, *args)
  enqueue_to(queue_from_class(klass), klass, *args)
end
enqueue_front() click to toggle source
# File lib/resque.rb, line 216
def enqueue_front
  if defined? @enqueue_front
    @enqueue_front
  else
    @enqueue_front = false
  end
end
enqueue_to(queue, klass, *args) click to toggle source

Just like `enqueue` but allows you to specify the queue you want to use. Runs hooks.

`queue` should be the String name of the queue you're targeting.

Returns true if the job was queued, nil if the job was rejected by a before_enqueue hook.

This method is considered part of the `stable` API.

# File lib/resque.rb, line 445
def enqueue_to(queue, klass, *args)
  # Perform before_enqueue hooks. Don't perform enqueue if any hook returns false
  before_hooks = Plugin.before_enqueue_hooks(klass).collect do |hook|
    klass.send(hook, *args)
  end
  return nil if before_hooks.any? { |result| result == false }

  Job.create(queue, klass, *args)

  Plugin.after_enqueue_hooks(klass).each do |hook|
    klass.send(hook, *args)
  end

  return true
end
heartbeat_interval() click to toggle source
# File lib/resque.rb, line 193
def heartbeat_interval
  if defined? @heartbeat_interval
    @heartbeat_interval
  else
    DEFAULT_HEARTBEAT_INTERVAL
  end
end
info() click to toggle source

Returns a hash, similar to redis-rb's info, of interesting stats.

# File lib/resque.rb, line 564
def info
  return {
    :pending   => queue_sizes.inject(0) { |sum, (_queue_name, queue_size)| sum + queue_size },
    :processed => Stat[:processed],
    :queues    => queues.size,
    :workers   => workers.size.to_i,
    :working   => working.size,
    :failed    => data_store.num_failed,
    :servers   => [redis_id],
    :environment  => ENV['RAILS_ENV'] || ENV['RACK_ENV'] || 'development'
  }
end
keys() click to toggle source

Returns an array of all known Resque keys in Redis. Redis' KEYS operation is O(N) for the keyspace, so be careful - this can be slow for big databases.

# File lib/resque.rb, line 579
def keys
  data_store.all_resque_keys
end
list_range(key, start = 0, count = 1) click to toggle source

Does the dirty work of fetching a range of items from a Redis list and converting them into Ruby objects.

# File lib/resque.rb, line 386
def list_range(key, start = 0, count = 1)
  results = data_store.list_range(key, start, count)
  if count == 1
    decode(results)
  else
    results.map { |result| decode(result) }
  end
end
peek(queue, start = 0, count = 1) click to toggle source

Returns an array of items currently queued. Queue name should be a string.

start and count should be integer and can be used for pagination. start is the item to begin, count is how many items to return.

To get the 3rd page of a 30 item, paginatied list one would use:

Resque.peek('my_list', 59, 30)
# File lib/resque.rb, line 375
def peek(queue, start = 0, count = 1)
  results = data_store.peek_in_queue(queue,start,count)
  if count == 1
    decode(results)
  else
    results.map { |result| decode(result) }
  end
end
pop(queue) click to toggle source

Pops a job off a queue. Queue name should be a string.

Returns a Ruby object.

# File lib/resque.rb, line 357
def pop(queue)
  decode(data_store.pop_from_queue(queue))
end
prune_interval() click to toggle source
# File lib/resque.rb, line 203
def prune_interval
  if defined? @prune_interval
    @prune_interval
  else
    DEFAULT_PRUNE_INTERVAL
  end
end
push(queue, item) click to toggle source

Pushes a job onto a queue. Queue name should be a string and the item should be any JSON-able Ruby object.

Resque works generally expect the `item` to be a hash with the following keys:

class - The String name of the job to run.
 args - An Array of arguments to pass the job. Usually passed
        via `class.to_class.perform(*args)`.

Example

Resque.push('archive', :class => 'Archive', :args => [ 35, 'tar' ])

Returns nothing

# File lib/resque.rb, line 350
def push(queue, item)
  data_store.push_to_queue(queue,encode(item))
end
queue_empty(&block) click to toggle source

The `queue_empty` hook will be run in the parent process when the worker finds no more jobs in the queue and becomes idle.

Call with a block to register a hook. Call with no arguments to return all registered hooks.

# File lib/resque.rb, line 297
def queue_empty(&block)
  block ? register_hook(:queue_empty, block) : hooks(:queue_empty)
end
queue_empty=(block) click to toggle source

Register a queue_empty proc.

# File lib/resque.rb, line 302
def queue_empty=(block)
  register_hook(:queue_empty, block)
end
queue_from_class(klass) click to toggle source

Given a class, try to extrapolate an appropriate queue based on a class instance variable or `queue` method.

# File lib/resque.rb, line 506
def queue_from_class(klass)
  (klass.instance_variable_defined?(:@queue) && klass.instance_variable_get(:@queue)) ||
    (klass.respond_to?(:queue) and klass.queue)
end
queue_sizes() click to toggle source

Returns a hash, mapping queue names to queue sizes

# File lib/resque.rb, line 584
def queue_sizes
  queue_names = queues

  sizes = redis.pipelined do
    queue_names.each do |name|
      redis.llen("queue:#{name}")
    end
  end

  Hash[queue_names.zip(sizes)]
end
queues() click to toggle source

Returns an array of all known Resque queues as strings.

# File lib/resque.rb, line 396
def queues
  data_store.queue_names
end
redis() click to toggle source

Returns the current Redis connection. If none has been created, will create a new one.

# File lib/resque.rb, line 141
def redis
  return @data_store if @data_store
  self.redis = Redis.respond_to?(:connect) ? Redis.connect : "localhost:6379"
  self.redis
end
Also aliased as: data_store
redis=(server) click to toggle source

Accepts:

1. A 'hostname:port' String
2. A 'hostname:port:db' String (to select the Redis db)
3. A 'hostname:port/namespace' String (to set the Redis namespace)
4. A Redis URL String 'redis://host:port'
5. An instance of `Redis`, `Redis::Client`, `Redis::DistRedis`,
   or `Redis::Namespace`.
6. An Hash of a redis connection {:host => 'localhost', :port => 6379, :db => 0}
# File lib/resque.rb, line 114
def redis=(server)
  case server
  when String
    if server =~ /rediss?\:\/\//
      redis = Redis.new(:url => server, :thread_safe => true)
    else
      server, namespace = server.split('/', 2)
      host, port, db = server.split(':')
      redis = Redis.new(:host => host, :port => port,
        :thread_safe => true, :db => db)
    end
    namespace ||= :resque

    @data_store = Resque::DataStore.new(Redis::Namespace.new(namespace, :redis => redis))
  when Redis::Namespace
    @data_store = Resque::DataStore.new(server)
  when Resque::DataStore
    @data_store = server
  when Hash
    @data_store = Resque::DataStore.new(Redis::Namespace.new(:resque, :redis => Redis.new(server)))
  else
    @data_store = Resque::DataStore.new(Redis::Namespace.new(:resque, :redis => server))
  end
end
redis_id() click to toggle source
# File lib/resque.rb, line 148
def redis_id
  data_store.identifier
end
remove_queue(queue) click to toggle source

Given a queue name, completely deletes the queue.

# File lib/resque.rb, line 401
def remove_queue(queue)
  data_store.remove_queue(queue)
end
remove_worker(worker_id) click to toggle source

A shortcut to unregister_worker useful for command line tool

# File lib/resque.rb, line 554
def remove_worker(worker_id)
  worker = Resque::Worker.find(worker_id)
  worker.unregister_worker
end
reserve(queue) click to toggle source

This method will return a `Resque::Job` object or a non-true value depending on whether a job can be obtained. You should pass it the precise name of a queue: case matters.

This method is considered part of the `stable` API.

# File lib/resque.rb, line 516
def reserve(queue)
  Job.reserve(queue)
end
sample_queues(sample_size = 1000) click to toggle source

Returns a hash, mapping queue names to (up to `sample_size`) samples of jobs in that queue

# File lib/resque.rb, line 597
def sample_queues(sample_size = 1000)
  queue_names = queues

  samples = redis.pipelined do
    queue_names.each do |name|
      key = "queue:#{name}"
      redis.llen(key)
      redis.lrange(key, 0, sample_size - 1)
    end
  end

  hash = {}

  queue_names.zip(samples.each_slice(2).to_a) do |queue_name, (queue_size, serialized_samples)|
    samples = serialized_samples.map do |serialized_sample|
      Job.decode(serialized_sample)
    end

    hash[queue_name] = {
      :size => queue_size,
      :samples => samples
    }
  end

  hash
end
size(queue) click to toggle source

Returns an integer representing the size of a queue. Queue name should be a string.

# File lib/resque.rb, line 363
def size(queue)
  data_store.queue_size(queue)
end
stat_data_store() click to toggle source

Returns the data store for the statistics module.

# File lib/resque.rb, line 180
def stat_data_store
  Resque::Stat.data_store
end
stat_data_store=(stat_data_store) click to toggle source

Set the data store for the processed and failed statistics.

By default it uses the same as `Resque.redis`, but different stores can be used.

A custom store needs to obey the following API to work correctly

class NullDataStore

# Returns the current value for the given stat.
def stat(stat)
end

# Increments the stat by the given value.
def increment_stat(stat, by)
end

# Decrements the stat by the given value.
def decrement_stat(stat, by)
end

# Clear the values for the given stat.
def clear_stat(stat)
end

end

# File lib/resque.rb, line 175
def stat_data_store=(stat_data_store)
  Resque::Stat.data_store = stat_data_store
end
to_s() click to toggle source
# File lib/resque.rb, line 320
def to_s
  "Resque Client connected to #{redis_id}"
end
validate(klass, queue = nil) click to toggle source

Validates if the given klass could be a valid Resque job

If no queue can be inferred this method will raise a `Resque::NoQueueError`

If given klass is nil this method will raise a `Resque::NoClassError`

# File lib/resque.rb, line 525
def validate(klass, queue = nil)
  queue ||= queue_from_class(klass)

  if !queue
    raise NoQueueError.new("Jobs must be placed onto a queue. No queue could be inferred for class #{klass}")
  end

  if klass.to_s.empty?
    raise NoClassError.new("Jobs must be given a class.")
  end
end
watch_queue(queue) click to toggle source

Used internally to keep track of which queues we've created. Don't call this directly.

# File lib/resque.rb, line 407
def watch_queue(queue)
  data_store.watch_queue(queue)
end
worker_exit(&block) click to toggle source

The `worker_exit` hook will be run in the parent process after the worker has existed (via SIGQUIT, SIGTERM, SIGINT, etc.).

Call with a block to register a hook. Call with no arguments to return all registered hooks.

# File lib/resque.rb, line 311
def worker_exit(&block)
  block ? register_hook(:worker_exit, block) : hooks(:worker_exit)
end
worker_exit=(block) click to toggle source

Register a worker_exit proc.

# File lib/resque.rb, line 316
def worker_exit=(block)
  register_hook(:worker_exit, block)
end
workers() click to toggle source

A shortcut to Worker.all

# File lib/resque.rb, line 543
def workers
  Worker.all
end
working() click to toggle source

A shortcut to Worker.working

# File lib/resque.rb, line 548
def working
  Worker.working
end

Private Instance Methods

clear_hooks(name) click to toggle source

Clear all hooks given a hook name.

# File lib/resque.rb, line 640
def clear_hooks(name)
  @hooks[name] = []
end
hooks(name) click to toggle source

Retrieve all hooks of a given name.

# File lib/resque.rb, line 645
def hooks(name)
  @hooks[name]
end
register_hook(name, block) click to toggle source

Register a new proc as a hook. If the block is nil this is the equivalent of removing all hooks of the given name.

`name` is the hook that the block should be registered with.

# File lib/resque.rb, line 632
def register_hook(name, block)
  return clear_hooks(name) if block.nil?

  block = Array(block)
  @hooks[name].concat(block)
end