RubyCron
Define your cronjobs in your favorite language, and get reporting for free!
By letting RubyCron deal with warnings, errors, and sending reports, you can focus on writing clean and effective cronjobs in Ruby.
Author
- Bart Kamphorst
Installation
#> gem install rubycron
Dependencies
This gem depends on Mikel's wonderful mail gem.
By default, RubyCron assumes you have a local smtp server running on port 25 in order to send mail.
Tested on
- ruby-1.8.7-p374 [ i686 ]
- ruby-1.9.2-p320 [ x86_64 ]
- ruby-1.9.3-p448 [ x86_64 ]
- ruby-2.0.0-p451 [ x86_64 ]
- ruby-2.1.1
- jruby-1.7.11 [ x86_64 ]
Usage
Configure the basics
Open a new file, require and include RubyCron, and then initialize a new RubyCronJob as follows:
rcj = RubyCronJob.new( :author => 'John Doe',
:name => 'test',
:mailto => '[email protected]' )
Write your cronjob
Call RubyCronJob's execute method, and define your cronjob within the do-end block. Use the info, warning and error methods to create your reports.
rcj.execute do
info "Starting run on #{`uname -n`}"
unless File.directory?(Dir.tmpdir)
warning "Something seems wrong with the tmp directory."
end
begin
File.open('/tmp/rubycrontest', 'w') do |f|
f.write("Test completed successfully.")
end
rescue => e
error "Something went wrong trying to write to file: #{e.}"
end
end
That's it! Now when you run this cronjob, you will receive a report by email.
Set up Cron
To activate the cronjob, add it to your crontab like any other cronjob. There are, however, two ways to do this: run the RubyCronJob as a stand-alone script, or have the RubyCronJob be executed by rcjrunner.rb.
Stand-alone
For the stand-alone option, add a crontab entry like so:
min hour mday month wday command
* * * * * test.rcj
For this to work properly, make sure your rubycronjob (test.rcj in this example) starts with a shebang and is executable.
Using rcjrunner.rb
Simply feed your rubycronjob to rcjrunner.rb as a command-line argument in your crontab entry:
min hour mday month wday command
* * * * * rcjrunner.rb test.rcj
Other configuration options
I now get all these reports, but I really only care if the job fails!
Sorting through hundreds of cron mails per day that report successful runs may be gratifying at times, but most sane people only care to be notified when their cronjobs fail. Not to worry, just add the following line to the RubyCronJob's initialization hash.
:mailon => :error
RubyCron will now only report when errors occurred during the run. Other options are :none, :warning and :all (default).
All emails originate from root@localhost. Can I change that?
Of course. Use
:mailfrom => '[email protected]'
to change the From:-header.
Do I really have to configure a local smtp server to send mail?
No. You can use other smtp servers for delivery like so:
smtpsettings = { :address => 'smtp.gmail.com',
:port => 587,
:domain => 'your.host.name',
:user_name => '<username>',
:password => '<password>',
:authentication => 'plain',
:enable_starttls_auto => true }
rcj = RubyCronJob.new( :author => 'John Doe',
:name => 'test',
:mailto => '[email protected]',
:mailfrom => '[email protected]',
:smtpsettings => smtpsettings )
I want my cronjob to stop running when there are errors.
No problem. You can configure this behavior with
:exiton => :all
Valid values are :none (default), :warning, :error, :all.
Is there a way to manipulate the content of the email reports?
There sure is. Simply write your own ERB template, and tell the RubyCronJob about it with the :template directive.
rcj = RubyCronJob.new(
:author => 'John Doe',
:name => 'test',
:mailto => '[email protected]',
:mailfrom => '[email protected]',
:template => 'my_template.erb' )
Note that from inside the ERB template (my_template.erb in the above example) you have access to the @warnings and @errors arrays.
May I please see some output while I'm developing my cronjob?
Output to stdout and stderr can be very useful when debugging your cronjob. Just set the verbose flag to true:
:verbose => true
Is er there a debug mode?
Absolutely:
:debug => true
This is roughly the equivalent of setting :verbose to true and :mailon to :none. It allows you to test your cronjobs without being spammed.
As a sysadmin, I like grepping through files. Can I have a log file please?
Yes. Set a file path in RubyCronJob's logfile variable, and all output will be redirected to file:
:logfile => '/tmp/rcjlogfile.log'
Note that you will still receive email reports when you enable file logging.
I like all these different options, but can't I set some of them globally for all my cronjobs?
Anything to prevent redundancy, right? Use the :configfile and :configurl directives to point towards YAML files that hold your configuration hashes. For instance, this works:
rcj = RubyCronJob.new( :configfile => "my_config_file.yml" )
Or this:
rcj = RubyCronJob.new( :configurl => "http://www.foo.bar/my_config.yml")
Or even a combination:
rcj = RubyCronJob.new( :configfile => "my_config_file.yml",
:configurl => "http://www.foo.bar/my_config.yml",
:author => 'John Doe' )
Note that in the latter case the values of the directives specified within the RubyCronJob itself will take precedence over the file or url directives.
License
Copyright (c) 2011 - 2015, Bart Kamphorst
(Modified BSD License)
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
- Neither the name of the organization nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL