C4/BackgroundJob.pm

   1 package C4::BackgroundJob;
   2
   3 # Copyright (C) 2007 LibLime
   4 # Galen Charlton <galen.charlton@liblime.com>
   5 #
   6 # This file is part of Koha.
   7 #
   8 # Koha is free software; you can redistribute it and/or modify it under the
   9 # terms of the GNU General Public License as published by the Free Software
  10 # Foundation; either version 2 of the License, or (at your option) any later
  11 # version.
  12 #
  13 # Koha is distributed in the hope that it will be useful, but WITHOUT ANY
  14 # WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  15 # A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License along
  18 # with Koha; if not, write to the Free Software Foundation, Inc.,
  19 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20
  21 use strict;
  22 #use warnings; FIXME - Bug 2505
  23 use C4::Context;
  24 use C4::Auth qw/get_session/;
  25 use Digest::MD5;
  26
  27 use vars qw($VERSION);
  28
  29 BEGIN {
  30         # set the version for version checking
  31     $VERSION = 3.07.00.049;
  32 }
  33
  34 =head1 NAME
  35
  36 C4::BackgroundJob - manage long-running jobs
  37 initiated from the web staff interface
  38
  39 =head1 SYNOPSIS
  40
  41  # start tracking a job
  42  my $job = C4::BackgroundJob->new($sessionID, $job_name, $job_invoker, $num_work_units);
  43  my $jobID = $job->id();
  44  $job->progress($work_units_processed);
  45  $job->finish($job_result_hashref);
  46
  47  # get status and results of a job
  48  my $job = C4::BackgroundJob->fetch($sessionID, $jobID);
  49  my $max_work_units = $job->size();
  50  my $work_units_processed = $job->progress();
  51  my $job_status = $job->status();
  52  my $job_name = $job->name();
  53  my $job_invoker = $job->invoker();
  54  my $results_hashref = $job->results();
  55
  56 This module manages tracking the progress and results
  57 of (potentially) long-running jobs initiated from
  58 the staff user interface.  Such jobs can include
  59 batch MARC and patron record imports.
  60
  61 =head1 METHODS
  62
  63 =head2 new
  64
  65  my $job = C4::BackgroundJob->new($sessionID, $job_name, $job_invoker, $num_work_units);
  66
  67 Create a new job object and set its status to 'running'.  C<$num_work_units>
  68 should be a number representing the size of the job; the units of the
  69 job size are up to the caller and could be number of records,
  70 number of bytes, etc.
  71
  72 =cut
  73
  74 sub new {
  75     my $class = shift;
  76     my ($sessionID, $job_name, $job_invoker, $num_work_units) = @_;
  77
  78     my $self = {};
  79     $self->{'sessionID'} = $sessionID;
  80     $self->{'name'} = $job_name;
  81     $self->{'invoker'} = $job_invoker;
  82     $self->{'size'} = $num_work_units;
  83     $self->{'progress'} = 0;
  84     $self->{'status'} = "running";
  85     $self->{'jobID'} = Digest::MD5::md5_hex(Digest::MD5::md5_hex(time().{}.rand().{}.$$));
  86
  87     bless $self, $class;
  88     $self->_serialize();
  89
  90     return $self;
  91 }
  92
  93 # store object in CGI session
  94 sub _serialize {
  95     my $self = shift;
  96
  97     my $prefix = "job_" . $self->{'jobID'};
  98     my $session = get_session($self->{'sessionID'});
  99     $session->param($prefix, $self);
 100     $session->flush();
 101 }
 102
 103 =head2 id
 104
 105  my $jobID = $job->id();
 106
 107 Read-only accessor for job ID.
 108
 109 =cut
 110
 111 sub id {
 112     my $self = shift;
 113     return $self->{'jobID'};
 114 }
 115
 116 =head2 name
 117
 118  my $name = $job->name();
 119  $job->name($name);
 120
 121 Read/write accessor for job name.
 122
 123 =cut
 124
 125 sub name {
 126     my $self = shift;
 127     if (@_) {
 128         $self->{'name'} = shift;
 129         $self->_serialize();
 130     } else {
 131         return $self->{'name'};
 132     }
 133 }
 134
 135 =head2 invoker
 136
 137  my $invoker = $job->invoker();
 138 i $job->invoker($invoker);
 139
 140 Read/write accessor for job invoker.
 141
 142 =cut
 143
 144 sub invoker {
 145     my $self = shift;
 146     if (@_) {
 147         $self->{'invoker'} = shift;
 148         $self->_serialize();
 149     } else {
 150         return $self->{'invoker'};
 151     }
 152 }
 153
 154 =head2 progress
 155
 156  my $progress = $job->progress();
 157  $job->progress($progress);
 158
 159 Read/write accessor for job progress.
 160
 161 =cut
 162
 163 sub progress {
 164     my $self = shift;
 165     if (@_) {
 166         $self->{'progress'} = shift;
 167         $self->_serialize();
 168     } else {
 169         return $self->{'progress'};
 170     }
 171 }
 172
 173 =head2 status
 174
 175  my $status = $job->status();
 176
 177 Read-only accessor for job status.
 178
 179 =cut
 180
 181 sub status {
 182     my $self = shift;
 183     return $self->{'status'};
 184 }
 185
 186 =head2 size
 187
 188  my $size = $job->size();
 189  $job->size($size);
 190
 191 Read/write accessor for job size.
 192
 193 =cut
 194
 195 sub size {
 196     my $self = shift;
 197     if (@_) {
 198         $self->{'size'} = shift;
 199         $self->_serialize();
 200     } else {
 201         return $self->{'size'};
 202     }
 203 }
 204
 205 =head2 finish
 206
 207  $job->finish($results_hashref);
 208
 209 Mark the job as finished, setting its status to 'completed'.
 210 C<$results_hashref> should be a reference to a hash containing
 211 the results of the job.
 212
 213 =cut
 214
 215 sub finish {
 216     my $self = shift;
 217     my $results_hashref = shift;
 218     $self->{'status'} = 'completed';
 219     $self->{'results'} = $results_hashref;
 220     $self->_serialize();
 221 }
 222
 223 =head2 results
 224
 225  my $results_hashref = $job->results();
 226
 227 Retrieve the results of the current job.  Returns undef
 228 if the job status is not 'completed'.
 229
 230 =cut
 231
 232 sub results {
 233     my $self = shift;
 234     return unless $self->{'status'} eq 'completed';
 235     return $self->{'results'};
 236 }
 237
 238 =head2 fetch
 239
 240  my $job = C4::BackgroundJob->fetch($sessionID, $jobID);
 241
 242 Retrieve a job that has been serialized to the database.
 243 Returns C<undef> if the job does not exist in the current
 244 session.
 245
 246 =cut
 247
 248 sub fetch {
 249     my $class = shift;
 250     my $sessionID = shift;
 251     my $jobID = shift;
 252
 253     my $session = get_session($sessionID);
 254     my $prefix = "job_$jobID";
 255     unless (defined $session->param($prefix)) {
 256         return;
 257     }
 258     my $self = $session->param($prefix);
 259     bless $self, $class;
 260     return $self;
 261 }
 262
 263 1;
 264 __END__
 265
 266 =head1 AUTHOR
 267
 268 Koha Development Team <http://koha-community.org/>
 269
 270 Galen Charlton <galen.charlton@liblime.com>
 271
 272 =cut