Rails3利用whenever gem调度发送邮件

1. Install

$ gem install whenever

Or with Bundler in your Gemfile.

gem 'whenever', :require => false

2. Getting Started

$ cd /my/rails/app
$ wheneverize .

This will create an initial "config/schedule.rb" file you.

config/schedule.rb

# Learn more: http://github.com/javan/whenever

set :output, "#{path}/log/whenever.log"

every 15.minutes do

  rake "send_emails"

end

 

3. Rake Tasks

desc "send emails"

task :send_emails do

  command = "ar_sendmail_rails3 -o -e #{Rails.env}"

  `#{command}`

end

4. Command

The whenever command

$ cd /my/rails/app
$ whenever

This will simply show you your schedule.rb file converted to cron syntax. It does not read or write your crontab file. Run whenever --help for a complete list of options.

Usage: whenever [options]

    -i [identifier],                 Default: full path to schedule.rb file

        --update-crontab

    -w, --write-crontab [identifier] Default: full path to schedule.rb file

    -c, --clear-crontab [identifier]

    -s, --set [variables]            Example: --set environment=staging&path=/my/sweet/path

    -f, --load-file [schedule file]  Default: config/schedule.rb

    -u, --user [user]                Default: current user

    -k, --cut [lines]                Cut lines from the top of the cronfile

    -v, --version

5. Add cron job

$ cd /my/rails/app
$ whenever -s environment=qa -w AC

6. Update cron job

$ cd /my/rails/app
$ whenever -i AC

7. Clear cron job

$ cd /my/rails/app
$ whenever -c AC

8. Capistrano

namespace :deploy do

...  

desc "Stop the existing cron job"

  task :stop_cron, :roles=>:app do

    run("crontab -r")

  end

  desc "Update the crontab file"

  task :update_crontab, :roles => :db do

    run "cd #{current_path} && whenever --set environment=#{rails_env} --update-crontab #{application}"

  end

....

end

After Task

after "deploy:symlink","deploy:update_crontab"

9. Tips

If you use RVM, you should install it on system root path or make a soft link to rake. Maybe whenever can't find rake in /usr/bin/.

More: https://github.com/javan/whenever