webgui/lib/Spectre/Workflow.pm
2006-03-17 02:07:50 +00:00

363 lines
10 KiB
Perl

package Spectre::Workflow;
=head1 LEGAL
-------------------------------------------------------------------
WebGUI is Copyright 2001-2006 Plain Black Corporation.
-------------------------------------------------------------------
Please read the legal notices (docs/legal.txt) and the license
(docs/license.txt) that came with this distribution before using
this software.
-------------------------------------------------------------------
http://www.plainblack.com info@plainblack.com
-------------------------------------------------------------------
=cut
use strict;
use Crypt::Blowfish;
use JSON;
use POE;
use POE::Component::Client::UserAgent;
#-------------------------------------------------------------------
=head2 _start ( )
Initializes the workflow manager.
=cut
sub _start {
my ( $kernel, $self, $publicEvents) = @_[ KERNEL, OBJECT, ARG0 ];
$self->debug("Starting workflow manager.");
my $serviceName = "workflow";
$kernel->alias_set($serviceName);
$kernel->call( IKC => publish => $serviceName, $publicEvents );
$self->debug("Reading workflow configs.");
my $configs = WebGUI::Config->readAllConfigs($self->config->getWebguiRoot);
foreach my $config (keys %{$configs}) {
$kernel->yield("loadWorkflows", $config);
}
$kernel->yield("checkJobs");
}
#-------------------------------------------------------------------
=head2 _stop ( )
Gracefully shuts down the workflow manager.
=cut
sub _stop {
my ($kernel, $self) = @_[KERNEL, OBJECT];
$self->debug("Stopping workflow manager.");
undef $self;
}
#-------------------------------------------------------------------
=head2 addJob ( config, job )
Adds a workflow job to the workflow processing queue.
=head3 config
The config file name for the site that this job belongs to.
=head3 job
A hash reference containing a row of data from the WorkflowInstance table.
=cut
sub addJob {
my ($self, $config, $job) = @_[OBJECT, ARG0, ARG1];
$self->debug->("Adding workflow instance ".$job->{instanceId}." from ".$config." to job queue at priority ".$job->{priority}.".");
# job list
$self->{_jobs}{$job->{instanceId}} = {
instanceId=>$job->{instanceId},
config=>$config,
status=>"waiting",
priority=>$job->{priority}
};
push(@{$self->{"_priority".$job->{priority}}}, $self->{_jobs}{$job->{instanceId}});
}
#-------------------------------------------------------------------
=head2 checkJobs ( )
Checks to see if there are any open job slots available, and if there are assigns a new job to be run to fill it.
=cut
sub checkJobs {
my ($kernel, $self) = @_[KERNEL, OBJECT];
$self->debug("Checking to see if we can run anymore jobs right now.");
if ($self->countRunningJobs < $self->config->get("maxWorkers")) {
my $job = $self->getNextJob;
if (defined $job) {
$job->{status} = "running";
push(@{$self->{_runningJobs}}, $job);
$kernel->yield("runWorker",$job);
}
}
$kernel->delay_set("checkJobs",$self->config->get("timeBetweenJobs"));
}
#-------------------------------------------------------------------
=head2 config
Returns a reference to the config object.
=cut
sub config {
my $self = shift;
return $self->{_config};
}
#-------------------------------------------------------------------
=head2 countRunningJobs ( )
Returns an integer representing the number of running jobs.
=cut
sub countRunningJobs {
my $self = shift;
my $runningJobs = $self->{_runningJobs} || [];
my $jobCount = scalar(@{$runningJobs});
$self->debug("There are $jobCount running jobs.");
return $jobCount;
}
#-------------------------------------------------------------------
=head2 debug ( output )
Prints out debug information if debug is enabled.
=head3
=cut
sub debug {
my $self = shift;
my $output = shift;
if ($self->{_debug}) {
print "WORKFLOW: ".$output."\n";
}
}
#-------------------------------------------------------------------
=head2 deleteJob ( instanceId )
Removes a workflow job from the processing queue.
=cut
sub deleteJob {
my ($self, $instanceId) = @_[OBJECT, ARG0];
$self->debug("Deleting workflow instance $instanceId from job queue.");
my $priority = $self->{_jobs}{$instanceId}{priority};
delete $self->{_jobs}{$instanceId};
for (my $i=0; $i < scalar(@{$self->{"_priority".$priority}}); $i++) {
if ($self->{"_priority".$priority}[$i]{instanceId} eq $instanceId) {
splice(@{$self->{"_priority".$priority}}, $i, 1);
}
}
}
#-------------------------------------------------------------------
=head2 getNextJob ( )
=cut
sub getNextJob {
my $self = shift;
$self->debug("Looking for a workflow instance to execute.");
foreach my $priority (1..3) {
foreach my $job (@{$self->{"_priority".$priority}}) {
if (time() > $job->{statusDelay} & $job->{status}) {
delete $job->{statusDelay};
$job->{status} eq "waiting";
}
if ($job->{status} eq "waiting") {
$self->debug("Looks like ".$job->{instanceId}." would be a good workflow instance to run.");
return $job;
}
}
}
$self->debug("Didn't see any workflow instances to run.");
return undef;
}
#-------------------------------------------------------------------
=head2 loadWorkflows ( )
=cut
sub loadWorkflows {
my ($kernel, $self, $config) = @_[KERNEL, OBJECT, ARG0];
$self->debug("Loading workflows for ".$config.".");
my $session = WebGUI::Session->open($self->config->getWebguiRoot, $config);
my $result = $session->db->read("select * from WorkflowInstance");
while (my $data = $result->hashRef) {
$kernel->yield("addJob", $config, $data);
}
$session->close;
}
#-------------------------------------------------------------------
=head2 new ( config [ , debug ] )
Constructor. Loads all active workflows from each WebGUI site and begins executing them.
=head3 config
The path to the root of the WebGUI installation.
=head3 debug
A boolean indicating Spectre should spew forth debug as it runs.
=cut
sub new {
my $class = shift;
my $config = shift;
my $debug = shift;
my $self = {_debug=>$debug, _config=>$config};
bless $self, $class;
my @publicEvents = qw(addJob deleteJob);
POE::Session->create(
object_states => [ $self => [qw(_start _stop checkJobs loadWorkflows runWorker), @publicEvents] ],
args=>[\@publicEvents]
);
}
#-------------------------------------------------------------------
=head2 runWorker ( )
Calls a worker to execute a workflow activity.
=cut
sub runWorker {
my ($kernel, $self, $job, $session) = @_[KERNEL, OBJECT, ARG0, SESSION];
$self->debug("Preparing to run workflow instance ".$job->{instanceId}.".");
POE::Component::Client::UserAgent->new;
my $url = $job->{sitename}.'/'.$job->{gateway};
$url =~ s/\/\//\//g;
$url = "http://".$url."?op=spectre;instanceId=".$job->{instanceId};
my $payload = {
'do'=>'runWorkflow',
instanceId=>$job->{instanceId},
};
my $cipher = Crypt::Blowfish->new($self->config->get("cryptoKey"));
my $request = HTTP::Request->new(POST => $url, Content => { op=>"spectre", payload=>$cipher->encrypt(objToJson($payload)) });
my $cookie = $self->{_cookies}{$job->{sitename}};
$request->header("Cookie","wgSession=".$cookie) if (defined $cookie);
$request->header("User-Agent","Spectre");
$request->header("X-JobId",$job->{instanceId});
$self->debug("Posting workflow instance ".$job->{instanceId}.".");
$kernel->post( useragent => 'request', { request => $request, response => $session->postback('workerResponse') });
$self->debug("Workflow instance ".$job->{instanceId}." posted.");
}
#-------------------------------------------------------------------
=head2 suspendJob ( jobId )
This method puts a running job back into the available jobs pool thusly freeing up a slot in the running jobs pool. This is done when a job has executed a workflow activity, but the entire workflow has not yet completed.
=head3 jobId
The job being suspended.
=cut
sub suspendJob {
my $self = shift;
my $instanceId = shift;
$self->debug("Suspending workflow instance ".$instanceId.".");
$self->{_jobs}{$instanceId}{status} = "delay";
$self->{_jobs}{$instanceId}{statusDelay} = $self->config->get("delayAfterSuspension") + time();
for (my $i=0; $i < scalar(@{$self->{_runningJobs}}); $i++) {
if ($self->{_runningJobs}[$i]{instanceId} eq $instanceId) {
splice(@{$self->{_runningJobs}}, $i, 1);
}
}
}
#-------------------------------------------------------------------
=head2 workerResponse ( )
This method is called when the response from the runWorker() method is received.
=cut
sub workerResponse {
my $self = $_[OBJECT];
$self->debug("Retrieving response from workflow instance job.");
my ($request, $response, $entry) = @{$_[ARG1]};
my $jobId = $request->header("X-JobId"); # got to figure out how to get this from the request, cuz the response may die
$self->debug("Response retrieved is for $jobId.");
if ($response->is_success) {
$self->debug("Response for $jobId retrieved successfully.");
if ($response->header("Cookie") ne "") {
$self->debug("Storing cookie for $jobId for later use.");
my $cookie = $response->header("Set-Cookie");
$cookie =~ s/wgSession=([a-zA-Z0-9\_\-]{22})/$1/;
$self->{_cookies}{$self->{_jobs}{$jobId}{sitename}} = $cookie;
}
my $cipher = Crypt::Blowfish->new($self->config->get("cryptoKey"));
my $payload = jsonToObj($cipher->decrypt($response->content));
my $state = $payload->{state};
if ($state eq "waiting") {
$self->debug("Was told to wait on $jobId because we're still waiting on some external event.");
$self->suspendJob($jobId);
} elsif ($state eq "complete") {
$self->debug("Workflow instance $jobId ran one of it's activities successfully.");
$self->suspendJob($jobId);
} elsif ($state eq "disabled") {
$self->debug("Workflow instance $jobId is disabled.");
$self->deleteJob($jobId);
} elsif ($state eq "done") {
$self->debug("Workflow instance $jobId is now complete.");
$self->deleteJob($jobId);
} elsif ($state eq "error") {
$self->debug("Got an error for $jobId.");
$self->suspendJob($jobId);
} else {
$self->debug("Something bad happened on the return of $jobId.");
$self->suspendJob($jobId);
# something bad happened
}
} elsif ($response->is_redirect) {
$self->debug("Response for $jobId was redirected.");
} elsif ($response->is_error) {
$self->debug("Response for $jobId had a communications error.");
$self->suspendJob($jobId)
# we should probably log something
}
}
1;