steadyops-dev/f3-cron

Job scheduling for the PHP Fat-Free Framework

Cron

Job scheduling for the PHP Fat-Free Framework

This plugin for Fat-Free Framework helps you control job scheduling directly from your web app.

• Operation and basic usage
• Schedule format
  • Crontab
  • Examples
  • Presets
• Options
  • Logging
  • CLI/Web interface
  • CLI path
• Ini configuration
• Asynchronicity
• API
• Potential improvements

Operation and basic usage

This plugin provides your app with an external interface to run scheduled jobs. The interface consists in 2 routes automatically added to your app:

• GET /cron checks for due jobs and executes them
• GET /cron/@job triggers a specific job

By default, this interface is accessible in CLI mode only and is meant to be called by the server job scheduler:

1. Unix cron or Windows Task Scheduler calls index.php /cron every minute (or at a slower rate).
2. index.php /cron checks for due jobs at that time and executes them, asynchronously if possible.

Step 1:

Configure your server job scheduler so that it calls php index.php /cron every minute.

Here's how to do it on a *nix server, assuming that your application resides in /path/to/app/index.php:

• create a file named, for example, mycrontab, containing the following line:

* * * * * cd /path/to/app; php index.php /cron

• configure cron with it, using the following command:

crontab mycrontab

NB: depending on your hosting, you may need to ask your provider to perform that step.

Step 2:

Instantiate the Cron class and define the list and frequency of jobs with the following commands:

//index.php
$f3=require('lib/base.php');
...
$cron=Cron::instance();
$cron->set('Job1','App->job1','@daily');
$cron->set('Job2','App->job2','@weekly');
...
$f3->run();

That's it!

Job1 will run every day and Job2 every week.

Schedule format

Crontab

Each job is scheduled using the (nearly) standard crontab format, which consists of 5 fields separated by spaces:

 * * * * *
 │ │ │ │ │
 │ │ │ │ │
 │ │ │ │ └───── day of week (0 - 6) (0 to 6 are Sunday to Saturday)
 │ │ │ └────────── month (1 - 12)
 │ │ └─────────────── day of month (1 - 31)
 │ └──────────────────── hour (0 - 23)
 └───────────────────────── min (0 - 59)

Each field may be:

• a *, meaning any value
• a number: 3
• a range: 1-4 (equals 1,2,3,4)
• a list of numbers or ranges: 1-4,6,8-10

Ranges have a default step value of 1, which can be adjusted using a /:

• 1-6/2 is the same as 1,3,5
• */3 is the same as 1,4,7,10 (month column)

Examples

$cron->set('Job1','App->job1','* * * * *'); // runs every minute
$cron->set('Job2','App->job2','*/5 * * * *'); // runs every 5 minutes
$cron->set('Job3','App->job3','0 8 * * 1'); // runs every Monday at 08:00
$cron->set('Job4','App->job4','0 4 10 * *'); // runs the 10th of each month at 04:00
$cron->set('Job5','App->job5','0 0 * */3 *'); // runs on a quarterly basis

Presets

For easier reading, it is possible to define presets:

$cron->preset('weekend','0 8 * * 6'); // runs every Saturday at 08:00
$cron->preset('lunch','0 12 * * *'); // runs every day at 12:00
$cron->set('Job6','App->job6','@weekend');
$cron->set('Job7','App->job7','@lunch');

The following presets are defined by default:

• @yearly or @annually <=> 0 0 1 1 *
• @monthly <=> 0 0 1 * *
• @weekly <=> 0 0 * * 0
• @daily <=> 0 0 * * *
• @hourly <=> 0 * * * *

Options

Logging

If you set $cron->log=TRUE, every successfully executed job will be logged in a cron.log file located in the TEMP folder.

CLI/Web interface

By default, the routes GET /cron and GET cron/@job are available in CLI mode only, which means that an HTTP request to them will throw a 404 error.

You can control that behavior with the 2 following public properties:

• $cron->cli determines if the routes are available in CLI mode (default: TRUE)
• $cron->web determines if the routes are available in Web mode (default: FALSE)

CLI path

By default, the script called asynchronously in CLI mode is index.php located in the current working directory.

You may need to tweak this value if:

• your web root differs from your app root (e.g: index.php resides in www/ and starts with chdir('..'))
• you want to handle all the scheduling in a separate file (e.g: cron.php instead of index.php)

Examples:

$cron->clipath='htdocs/index.php';//relative to app root
$cron->clipath=__DIR__.'/cron.php';//absolute path

Ini configuration

Configuration is possible from within an .ini file, using the CRON variable. E.g:

[CRON]
log = TRUE
cli = TRUE
web = FALSE
clipath = cron.php

[CRON.presets]
lunch = 0 12 * * *

[CRON.jobs]
Job1 = App->job1, * * * * *
Job2 = App->job2, @lunch
Job3 = App->job3, @hourly

IMPORTANT: Don't forget to instantiate the class before running your app:

//index.php
$f3=require('lib/base.php')
$f3->config('cron.ini');
Cron::instance(); // <--- MANDATORY
$f3->run();

Asynchronicity

If you want tasks to be run asynchronously, you'll need:

• exec() to be enabled on your hosting
• the php executable to be executable and in the path of your hosting user

NB1: The plugin will detect automatically if jobs can be run asynchronously. If not, jobs will be executed synchronously, which may take longer and add a risk of queue loss in case of a job failure.

NB2: Asynchronicity is not available on Windows at the moment. File an issue if you need it.

API

$cron = Cron::instance();

log

Logging of successfully executed jobs (default=FALSE)

$cron->log=TRUE;// enable logging

cli

CLI interface (default=TRUE)

$cron->cli=FALSE;// disable CLI interface

web

Web interface (default=FALSE)

$cron->web=TRUE;// enable web interface

clipath

Path of the script to call asynchronously in CLI mode

Defaults to index.php in the current working directory.

$cron->clipath='htdocs/index.php';//relative to app root
$cron->clipath=__DIR__.'/cron.php';//absolute path

set( $job, $handler, $expr )

Schedule a job

$cron->set('Job1','App->job1','@daily'); // runs daily
$cron->set('Job2','App->job2','*/5 * * * *'); // runs every 5 minutes
$cron->set('Job3','App->job3','0 8 * * 1'); // runs every Monday at 08:00

NB: Valid characters for job names are alphanumeric characters and hyphens.

preset( $name, $expr )

Define a schedule preset

$cron->preset('weekend','0 8 * * 6'); // runs every Saturday at 08:00
$cron->preset('lunch','0 12 * * *'); // runs every day at 12:00

NB: Valid characters for job names are alphanumeric characters.

isDue( $job, $time )

Returns TRUE if the requested job is due at the given time

$cron->isDue('Job3',time()); // returns TRUE if Job3 is due now

execute( $job, $async=TRUE )

Execute a job

$cron->execute('Job2',FALSE); // executes Job2 synchronously

run( $time=NULL, $async=TRUE )

Run scheduler, i.e executes all due jobs at a given time

$cron->run(strtotime('yesterday midnight'));
// run asynchronously all jobs due yesterday at midnight

Potential improvements

• Enable asynchronous execution on Windows.