Minion(3) Job queue


use Minion;
# Connect to backend
my $minion = Minion->new(Pg => 'postgresql://[email protected]/test');
# Add tasks
$minion->add_task(something_slow => sub {
my ($job, @args) = @_;
sleep 5;
say 'This is a background worker process.';
# Enqueue jobs
$minion->enqueue(something_slow => ['foo', 'bar']);
$minion->enqueue(something_slow => [1, 2, 3] => {priority => 5});
# Perform jobs for testing
$minion->enqueue(something_slow => ['foo', 'bar']);
# Build more sophisticated workers
my $worker = $minion->repair->worker;
while (int rand 2) {
if (my $job = $worker->register->dequeue(5)) { $job->perform }


Minion is a job queue for the Mojolicious <> real-time web framework, with support for multiple named queues, priorities, delayed jobs, job dependencies, job results, retries with backoff, statistics, distributed workers, parallel processing, autoscaling, resource leak protection and multiple backends (such as PostgreSQL <>).

Job queues allow you to process time and/or computationally intensive tasks in background processes, outside of the request/response lifecycle. Among those tasks you'll commonly find image resizing, spam filtering, HTTP downloads, building tarballs, warming caches and basically everything else you can imagine that's not super fast.

  use Mojolicious::Lite;
  plugin Minion => {Pg => 'postgresql://sri:[email protected]/test'};
  # Slow task
  app->minion->add_task(poke_mojo => sub {
    my $job = shift;
    $job->app->log->debug('We have poked for a visitor');
  # Perform job in a background worker process
  get '/' => sub {
    my $c = shift;
    $c->render(text => 'We will poke for you soon.');

Background worker processes are usually started with the command Minion::Command::minion::worker, which becomes automatically available when an application loads the plugin Mojolicious::Plugin::Minion.

  $ ./ minion worker

Jobs can be managed right from the command line with Minion::Command::minion::job.

  $ ./ minion job

Every job can fail or succeed, but not get lost, the system is eventually consistent and will preserve job results for as long as you like, depending on ``remove_after''. While individual workers can fail in the middle of processing a job, the system will detect this and ensure that no job is left in an uncertain state, depending on ``missing_after''.


And as your application grows, you can move tasks into application specific plugins.

  package MyApp::Task::PokeMojo;
  use Mojo::Base 'Mojolicious::Plugin';
  sub register {
    my ($self, $app) = @_;
    $app->minion->add_task(poke_mojo => sub {
      my $job = shift;
      $job->app->log->debug('We have poked for a visitor');

Which are loaded like any other plugin from your application.

  # Mojolicious
  # Mojolicious::Lite
  plugin 'MyApp::Task::PokeMojo';


Minion inherits all events from Mojo::EventEmitter and can emit the following new ones.


  $minion->on(enqueue => sub {
    my ($minion, $id) = @_;

Emitted after a job has been enqueued, in the process that enqueued it.

  $minion->on(enqueue => sub {
    my ($minion, $id) = @_;
    say "Job $id has been enqueued.";


  $minion->on(worker => sub {
    my ($minion, $worker) = @_;

Emitted in the worker process after it has been created.

  $minion->on(worker => sub {
    my ($minion, $worker) = @_;
    my $id = $worker->id;
    say "Worker $$:$id started.";


Minion implements the following attributes.


  my $app = $minion->app;
  $minion = $minion->app(MyApp->new);

Application for job queue, defaults to a Mojo::HelloWorld object.


  my $backend = $minion->backend;
  $minion     = $minion->backend(Minion::Backend::Pg->new);

Backend, usually a Minion::Backend::Pg object.


  my $cb  = $minion->backoff;
  $minion = $minion->backoff(sub {...});

A callback used to calculate the delay for automatically retried jobs, defaults to "(retries ** 4) + 15" (15, 16, 31, 96, 271, 640...), which means that roughly 25 attempts can be made in 21 days.

  $minion->backoff(sub {
    my $retries = shift;
    return ($retries ** 4) + 15 + int(rand 30);


  my $after = $minion->missing_after;
  $minion   = $minion->missing_after(172800);

Amount of time in seconds after which workers without a heartbeat will be considered missing and removed from the registry by ``repair'', defaults to 1800 (30 minutes).


  my $after = $minion->remove_after;
  $minion   = $minion->remove_after(86400);

Amount of time in seconds after which jobs that have reached the state "finished" and have no unresolved dependencies will be removed automatically by ``repair'', defaults to 172800 (2 days).


  my $tasks = $minion->tasks;
  $minion   = $minion->tasks({foo => sub {...}});

Registered tasks.


Minion inherits all methods from Mojo::EventEmitter and implements the following new ones.


  $minion = $minion->add_task(foo => sub {...});

Register a task.

  # Job with result
  $minion->add_task(add => sub {
    my ($job, $first, $second) = @_;
    $job->finish($first + $second);
  my $id = $minion->enqueue(add => [1, 1]);
  my $result = $minion->job($id)->info->{result};


  my $id = $minion->enqueue('foo');
  my $id = $minion->enqueue(foo => [@args]);
  my $id = $minion->enqueue(foo => [@args] => {priority => 1});

Enqueue a new job with "inactive" state. Arguments get serialized by the ``backend'' (often with Mojo::JSON), so you shouldn't send objects and be careful with binary data, nested data structures with hash and array references are fine though.

These options are currently available:

  attempts => 25

Number of times performing this job will be attempted, with a delay based on ``backoff'' after the first attempt, defaults to 1.

  delay => 10

Delay job for this many seconds (from now).

  parents => [$id1, $id2, $id3]

One or more existing jobs this job depends on, and that need to have transitioned to the state "finished" before it can be processed.

  priority => 5

Job priority, defaults to 0.

  queue => 'important'

Queue to put job in, defaults to "default".


  my $job = $minion->job($id);

Get Minion::Job object without making any changes to the actual job or return "undef" if job does not exist.

  # Check job state
  my $state = $minion->job($id)->info->{state};
  # Get job result
  my $result = $minion->job($id)->info->{result};


  my $minion = Minion->new(Pg => 'postgresql://[email protected]/test');

Construct a new Minion object.


  $minion->perform_jobs({queues => ['important']});

Perform all jobs with a temporary worker, very useful for testing.

  # Longer version
  my $worker = $minion->worker;
  while (my $job = $worker->register->dequeue(0)) { $job->perform }

These options are currently available:

  queues => ['important']

One or more queues to dequeue jobs from, defaults to "default".


  $minion = $minion->repair;

Repair worker registry and job queue if necessary.


  $minion = $minion->reset;

Reset job queue.


  my $stats = $minion->stats;

Get statistics for jobs and workers.

  # Check idle workers
  my $idle = $minion->stats->{inactive_workers};

These fields are currently available:

  active_jobs => 100

Number of jobs in "active" state.

  active_workers => 100

Number of workers that are currently processing a job.

  delayed_jobs => 100

Number of jobs in "inactive" state that are scheduled to run at specific time in the future or have unresolved dependencies. Note that this field is EXPERIMENTAL and might change without warning!

  failed_jobs => 100

Number of jobs in "failed" state.

  finished_jobs => 100

Number of jobs in "finished" state.

  inactive_jobs => 100

Number of jobs in "inactive" state.

  inactive_workers => 100

Number of workers that are currently not processing a job.


  my $worker = $minion->worker;

Build Minion::Worker object.


This is the class hierarchy of the Minion distribution.
  • Minion
  • Minion::Backend
  • Minion::Backend::Pg
  • Minion::Command::minion
  • Minion::Command::minion::job
  • Minion::Command::minion::worker
  • Minion::Job
  • Minion::Worker
  • Mojolicious::Plugin::Minion


Sebastian Riedel, "[email protected]".


In alphabetical order:

Andrey Khozov

Brian Medley

Joel Berger

Paul Williams


Copyright (C) 2014-2016, Sebastian Riedel and others.

This program is free software, you can redistribute it and/or modify it under the terms of the Artistic License version 2.0.