Module: Minion::Backend
Parent: Mojo::Base

NAME

Minion::Backend - Backend base class

SYNOPSIS

package Minion::Backend::MyBackend;
use Mojo::Base 'Minion::Backend';

sub broadcast         {...}
sub dequeue           {...}
sub enqueue           {...}
sub fail_job          {...}
sub finish_job        {...}
sub history           {...}
sub list_jobs         {...}
sub list_locks        {...}
sub list_workers      {...}
sub lock              {...}
sub note              {...}
sub receive           {...}
sub register_worker   {...}
sub remove_job        {...}
sub repair            {...}
sub reset             {...}
sub retry_job         {...}
sub stats             {...}
sub unlock            {...}
sub unregister_worker {...}

DESCRIPTION

Minion::Backend is an abstract base class for Minion backends, like Minion::Backend::Pg.

ATTRIBUTES

Minion::Backend implements the following attributes.

minion

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

Minion object this backend belongs to. Note that this attribute is weakened.

METHODS

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

auto_retry_job

my $bool = $backend->auto_retry_job($job_id, $retries, $attempts);

Automatically "retry" job with "backoff" in Minion if there are attempts left, used to implement backends like Minion::Backend::Pg.

broadcast

my $bool = $backend->broadcast('some_command');
my $bool = $backend->broadcast('some_command', [@args]);
my $bool = $backend->broadcast('some_command', [@args], [$id1, $id2, $id3]);

Broadcast remote control command to one or more workers. Meant to be overloaded in a subclass.

dequeue

my $job_info = $backend->dequeue($worker_id, 0.5);
my $job_info = $backend->dequeue($worker_id, 0.5, {queues => ['important']});

Wait a given amount of time in seconds for a job, dequeue it and transition from inactive to active state, or return undef if queues were empty. Meant to be overloaded in a subclass.

These options are currently available:

id
id => '10023'

Dequeue a specific job.

min_priority
min_priority => 3

Do not dequeue jobs with a lower priority.

queues
queues => ['important']

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

These fields are currently available:

args
args => ['foo', 'bar']

Job arguments.

id
id => '10023'

Job ID.

retries
retries => 3

Number of times job has been retried.

task
task => 'foo'

Task name.

enqueue

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

Enqueue a new job with inactive state. Meant to be overloaded in a subclass.

These options are currently available:

attempts
attempts => 25

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

delay
delay => 10

Delay job for this many seconds (from now), defaults to 0.

expire
expire => 300

Job is valid for this many seconds (from now) before it expires.

lax
lax => 1

Existing jobs this job depends on may also have transitioned to the failed state to allow for it to be processed, defaults to false. Note that this option is EXPERIMENTAL and might change without warning!

notes
notes => {foo => 'bar', baz => [1, 2, 3]}

Hash reference with arbitrary metadata for this job.

parents
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
priority => 5

Job priority, defaults to 0. Jobs with a higher priority get performed first. Priorities can be positive or negative, but should be in the range between 100 and -100.

queue
queue => 'important'

Queue to put job in, defaults to default.

fail_job

my $bool = $backend->fail_job($job_id, $retries);
my $bool = $backend->fail_job($job_id, $retries, 'Something went wrong!');
my $bool = $backend->fail_job(
  $job_id, $retries, {whatever => 'Something went wrong!'});

Transition from active to failed state with or without a result, and if there are attempts remaining, transition back to inactive with a delay based on "backoff" in Minion. Meant to be overloaded in a subclass.

finish_job

my $bool = $backend->finish_job($job_id, $retries);
my $bool = $backend->finish_job($job_id, $retries, 'All went well!');
my $bool = $backend->finish_job(
  $job_id, $retries, {whatever => 'All went well!'});

Transition from active to finished state with or without a result. Meant to be overloaded in a subclass.

history

my $history = $backend->history;

Get history information for job queue. Meant to be overloaded in a subclass.

These fields are currently available:

daily
daily => [{epoch => 12345, finished_jobs => 95, failed_jobs => 2}, ...]

Hourly counts for processed jobs from the past day.

list_jobs

my $results = $backend->list_jobs($offset, $limit);
my $results = $backend->list_jobs($offset, $limit, {states => ['inactive']});

Returns the information about jobs in batches. Meant to be overloaded in a subclass.

# Get the total number of results (without limit)
my $num = $backend->list_jobs(0, 100, {queues => ['important']})->{total};

# Check job state
my $results = $backend->list_jobs(0, 1, {ids => [$job_id]});
my $state = $results->{jobs}[0]{state};

# Get job result
my $results = $backend->list_jobs(0, 1, {ids => [$job_id]});
my $result  = $results->{jobs}[0]{result};

These options are currently available:

before
before => 23

List only jobs before this id.

ids
ids => ['23', '24']

List only jobs with these ids.

notes
notes => ['foo', 'bar']

List only jobs with one of these notes.

queues
queues => ['important', 'unimportant']

List only jobs in these queues.

states
states => ['inactive', 'active']

List only jobs in these states.

tasks
tasks => ['foo', 'bar']

List only jobs for these tasks.

These fields are currently available:

args
args => ['foo', 'bar']

Job arguments.

attempts
attempts => 25

Number of times performing this job will be attempted.

children
children => ['10026', '10027', '10028']

Jobs depending on this job.

created
created => 784111777

Epoch time job was created.

delayed
delayed => 784111777

Epoch time job was delayed to.

expires
expires => 784111777

Epoch time job is valid until before it expires.

finished
finished => 784111777

Epoch time job was finished.

id
id => 10025

Job id.

lax
lax => 0

Existing jobs this job depends on may also have failed to allow for it to be processed.

notes
notes => {foo => 'bar', baz => [1, 2, 3]}

Hash reference with arbitrary metadata for this job.

parents
parents => ['10023', '10024', '10025']

Jobs this job depends on.

priority
priority => 3

Job priority.

queue
queue => 'important'

Queue name.

result
result => 'All went well!'

Job result.

retried
retried => 784111777

Epoch time job has been retried.

retries
retries => 3

Number of times job has been retried.

started
started => 784111777

Epoch time job was started.

state
state => 'inactive'

Current job state, usually active, failed, finished or inactive.

task
task => 'foo'

Task name.

time
time => 78411177

Server time.

worker
worker => '154'

Id of worker that is processing the job.

list_locks

my $results = $backend->list_locks($offset, $limit);
my $results = $backend->list_locks($offset, $limit, {names => ['foo']});

Returns information about locks in batches. Meant to be overloaded in a subclass.

# Get the total number of results (without limit)
my $num = $backend->list_locks(0, 100, {names => ['bar']})->{total};

# Check expiration time
my $results = $backend->list_locks(0, 1, {names => ['foo']});
my $expires = $results->{locks}[0]{expires};

These options are currently available:

names
names => ['foo', 'bar']

List only locks with these names.

These fields are currently available:

expires
expires => 784111777

Epoch time this lock will expire.

id
id => 1

Lock id.

name
name => 'foo'

Lock name.

list_workers

my $results = $backend->list_workers($offset, $limit);
my $results = $backend->list_workers($offset, $limit, {ids => [23]});

Returns information about workers in batches. Meant to be overloaded in a subclass.

# Get the total number of results (without limit)
my $num = $backend->list_workers(0, 100)->{total};

# Check worker host
my $results = $backend->list_workers(0, 1, {ids => [$worker_id]});
my $host    = $results->{workers}[0]{host};

These options are currently available:

before
before => 23

List only workers before this id.

ids
ids => ['23', '24']

List only workers with these ids.

These fields are currently available:

id
id => 22

Worker id.

host
host => 'localhost'

Worker host.

jobs
jobs => ['10023', '10024', '10025', '10029']

Ids of jobs the worker is currently processing.

notified
notified => 784111777

Epoch time worker sent the last heartbeat.

pid
pid => 12345

Process id of worker.

started
started => 784111777

Epoch time worker was started.

status
status => {queues => ['default', 'important']}

Hash reference with whatever status information the worker would like to share.

lock

my $bool = $backend->lock('foo', 3600);
my $bool = $backend->lock('foo', 3600, {limit => 20});

Try to acquire a named lock that will expire automatically after the given amount of time in seconds. An expiration time of 0 can be used to check if a named lock already exists without creating one. Meant to be overloaded in a subclass.

These options are currently available:

limit
limit => 20

Number of shared locks with the same name that can be active at the same time, defaults to 1.

note

my $bool = $backend->note($job_id, {mojo => 'rocks', minion => 'too'});

Change one or more metadata fields for a job. Setting a value to undef will remove the field. Meant to be overloaded in a subclass.

receive

my $commands = $backend->receive($worker_id);

Receive remote control commands for worker. Meant to be overloaded in a subclass.

register_worker

my $worker_id = $backend->register_worker;
my $worker_id = $backend->register_worker($worker_id);
my $worker_id = $backend->register_worker(
  $worker_id, {status => {queues => ['default', 'important']}});

Register worker or send heartbeat to show that this worker is still alive. Meant to be overloaded in a subclass.

These options are currently available:

status
status => {queues => ['default', 'important']}

Hash reference with whatever status information the worker would like to share.

remove_job

my $bool = $backend->remove_job($job_id);

Remove failed, finished or inactive job from queue. Meant to be overloaded in a subclass.

repair

$backend->repair;

Repair worker registry and job queue if necessary. Meant to be overloaded in a subclass.

reset

$backend->reset({all => 1});

Reset job queue. Meant to be overloaded in a subclass.

These options are currently available:

all
all => 1

Reset everything.

locks
locks => 1

Reset only locks.

retry_job

my $bool = $backend->retry_job($job_id, $retries);
my $bool = $backend->retry_job($job_id, $retries, {delay => 10});

Transition job back to inactive state, already inactive jobs may also be retried to change options. Meant to be overloaded in a subclass.

These options are currently available:

attempts
attempts => 25

Number of times performing this job will be attempted.

delay
delay => 10

Delay job for this many seconds (from now), defaults to 0.

expire
expire => 300

Job is valid for this many seconds (from now) before it expires.

lax
lax => 1

Existing jobs this job depends on may also have transitioned to the failed state to allow for it to be processed, defaults to false. Note that this option is EXPERIMENTAL and might change without warning!

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

Jobs this job depends on.

priority
priority => 5

Job priority.

queue
queue => 'important'

Queue to put job in.

stats

my $stats = $backend->stats;

Get statistics for the job queue. Meant to be overloaded in a subclass.

These fields are currently available:

active_jobs
active_jobs => 100

Number of jobs in active state.

active_locks
active_locks => 100

Number of active named locks.

active_workers
active_workers => 100

Number of workers that are currently processing a job.

delayed_jobs
delayed_jobs => 100

Number of jobs in inactive state that are scheduled to run at specific time in the future or have unresolved dependencies.

enqueued_jobs
enqueued_jobs => 100000

Rough estimate of how many jobs have ever been enqueued.

failed_jobs
failed_jobs => 100

Number of jobs in failed state.

finished_jobs
finished_jobs => 100

Number of jobs in finished state.

inactive_jobs
inactive_jobs => 100

Number of jobs in inactive state.

inactive_workers
inactive_workers => 100

Number of workers that are currently not processing a job.

uptime
uptime => 1000

Uptime in seconds.

workers
workers => 200;

Number of registered workers.

unlock

my $bool = $backend->unlock('foo');

Release a named lock. Meant to be overloaded in a subclass.

unregister_worker

$backend->unregister_worker($worker_id);

Unregister worker. Meant to be overloaded in a subclass.

SEE ALSO

Minion, Minion::Guide, https://minion.pm, Mojolicious::Guides, https://mojolicious.org.