whenever/lib/command_line.rb

108 lines
3.2 KiB
Ruby

module Whenever
class CommandLine
def self.execute(options={})
new(options).run
end
def initialize(options={})
@options = options
@options[:file] ||= 'config/schedule.rb'
@options[:identifier] ||= default_identifier
unless File.exists?(@options[:file])
warn("[fail] Can't find file: #{@options[:file]}")
exit(1)
end
if @options[:update] && @options[:write]
warn("[fail] Can't update AND write. choose one.")
exit(1)
end
end
def run
if @options[:update]
write_crontab(updated_crontab)
elsif @options[:write]
write_crontab(whenever_cron)
else
puts Whenever.cron(:file => @options[:file])
exit
end
end
protected
def default_identifier
File.expand_path(@options[:file])
end
def whenever_cron
@whenever_cron ||= [comment_open, Whenever.cron(:file => @options[:file]), comment_close].join("\n")
end
def read_crontab
return @current_crontab if @current_crontab
command = ['crontab -l']
command << "-u #{@options[:user]}" if @options[:user]
command_results = %x[#{command.join(' ')} 2> /dev/null]
@current_crontab = $?.exitstatus.zero? ? command_results : ''
end
def write_crontab(contents)
tmp_cron_file = Tempfile.new('whenever_tmp_cron').path
File.open(tmp_cron_file, File::WRONLY | File::APPEND) do |file|
file << contents
end
command = ['crontab']
command << "-u #{@options[:user]}" if @options[:user]
command << tmp_cron_file
if system(command.join(' '))
action = 'written' if @options[:write]
action = 'updated' if @options[:update]
puts "[write] crontab file #{action}"
exit
else
warn "[fail] Couldn't write crontab; try running `whenever' with no options to ensure your schedule file is valid."
exit(1)
end
end
def updated_crontab
# Check for unopened or unclosed identifier blocks
if read_crontab.index(comment_open) && !read_crontab.index(comment_close)
warn "[fail] Unclosed indentifier; Your crontab file contains '#{comment_open}', but no '#{comment_close}'"
exit(1)
elsif !read_crontab.index(comment_open) && read_crontab.index(comment_close)
warn "[fail] Unopened indentifier; Your crontab file contains '#{comment_close}', but no '#{comment_open}'"
exit(1)
end
# If an existing identier block is found, replace it with the new cron entries
if read_crontab.index(comment_open) && read_crontab.index(comment_close)
read_crontab.gsub(Regexp.new("#{comment_open}.+#{comment_close}", Regexp::MULTILINE), whenever_cron)
else # Otherwise, append the new cron entries after any existing ones
[read_crontab, whenever_cron].join("\n\n")
end
end
def comment_base
"Whenever generated tasks for: #{@options[:identifier]}"
end
def comment_open
"# Begin #{comment_base}"
end
def comment_close
"# End #{comment_base}"
end
end
end