Gearman::Worker(3) User Contributed Perl Documentation Gearman::Worker(3)NAMEGearman::Worker - Worker for gearman distributed job system
SYNOPSIS
use Gearman::Worker;
my $worker = Gearman::Worker->new;
$worker->job_servers('127.0.0.1');
$worker->register_function($funcname => $subref);
$worker->work while 1;
DESCRIPTIONGearman::Worker is a worker class for the Gearman distributed job
system, providing a framework for receiving and serving jobs from a
Gearman server.
Callers instantiate a Gearman::Worker object, register a list of
functions and capabilities that they can handle, then enter an event
loop, waiting for the server to send jobs.
The worker can send a return value back to the server, which then gets
sent back to the client that requested the job; or it can simply
execute silently.
USAGE
Gearman::Worker->new(%options)
Creates a new Gearman::Worker object, and returns the object.
If %options is provided, initializes the new worker object with the
settings in %options, which can contain:
· job_servers
Calls job_servers (see below) to initialize the list of job
servers. It will be ignored if this worker is running as a child
process of a gearman server.
· prefix
Calls prefix (see below) to set the prefix / namespace.
$worker->job_servers(@servers)
Initializes the worker $worker with the list of job servers in
@servers. @servers should contain a list of IP addresses, with
optional port numbers. For example:
$worker->job_servers('127.0.0.1', '192.168.1.100:7003');
If the port number is not provided, 7003 is used as the default.
Calling this method will do nothing in a worker that is running as a
child process of a gearman server.
$worker->register_function($funcname, $subref)
$worker->register_function($funcname, $timeout, $subref)
Registers the function $funcname as being provided by the worker
$worker, and advertises these capabilities to all of the job servers
defined in this worker.
$subref must be a subroutine reference that will be invoked when the
worker receives a request for this function. It will be passed a
Gearman::Job object representing the job that has been received by the
worker.
$timeout is an optional parameter specifying how long the jobserver
will wait for your subroutine to give an answer. Exceeding this time
will result in the jobserver reassigning the task and ignoring your
result. This prevents a gimpy worker from ruining the 'user experience'
in many situations.
The subroutine reference can return a return value, which will be sent
back to the job server.
$client->prefix($prefix)
Sets the namespace / prefix for the function names. This is useful for
sharing job servers between different applications or different
instances of the same application (different development sandboxes for
example).
The namespace is currently implemented as a simple tab separated
concatentation of the prefix and the function name.
Gearman::Job->arg
Returns the scalar argument that the client sent to the job server.
Gearman::Job->set_status($numerator, $denominator)
Updates the status of the job (most likely, a long-running job) and
sends it back to the job server. $numerator and $denominator should
represent the percentage completion of the job.
Gearman::Job->work(%opts)
Do one job and returns (no value returned). You can pass "on_start"
"on_complete" and "on_fail" callbacks in %opts.
WORKERS AS CHILD PROCESSES
Gearman workers can be run run as child processes of a parent process
which embeds Gearman::Server. When such a parent process fork/execs a
worker, it sets the environment variable GEARMAN_WORKER_USE_STDIO to
true before launching the worker. If this variable is set to true, then
the jobservers function and option for new() are ignored and the unix
socket bound to STDIN/OUT are used instead as the IO path to the
gearman server.
EXAMPLES
Summation
This is an example worker that receives a request to sum up a list of
integers.
use Gearman::Worker;
use Storable qw( thaw );
use List::Util qw( sum );
my $worker = Gearman::Worker->new;
$worker->job_servers('127.0.0.1');
$worker->register_function(sum => sub { sum @{ thaw($_[0]->arg) } });
$worker->work while 1;
See the Gearman::Client documentation for a sample client sending the
sum job.
perl v5.14.1 2009-10-05 Gearman::Worker(3)
