Class: RQ::Snapshotter

Inherits:
MainHelper show all
Defined in:
lib/rq/snapshotter.rb

Overview

a Snapshotter is responsible for safely making a hot snapshot of a queue’s db. it’s very useful to make a snapshot if, for instance, you are working out a complex query over several attempts since each attempt will compete with other processes for the queue’s lock. by making a snapshot you will have your own read only copy to perfect your command before applying it to the actual queue. the feature can also be used to make a hot backup of a queue - tough the Backer has some features that make this more convenient

Constant Summary

Constants included from Logging

Logging::DIV0, Logging::DIV1, Logging::DIV2, Logging::DIV3, Logging::EOL, Logging::SEC0, Logging::SEC1, Logging::SEC2, Logging::SEC3

Instance Attribute Summary

Attributes inherited from MainHelper

#argv, #cmd, #dot_rq_dir, #env, #fields, #job_stdin, #loops, #main, #mode, #options, #program, #q, #qpath, #quiet, #stdin

Instance Method Summary collapse

Methods inherited from MainHelper

#dumping_yaml_tuples, #field_match, #init_job_stdin!, #initialize, #loadio, #loadyaml, #set_q

Methods included from Logging

append_features

Methods included from Logging::LogMethods

#debug, #error, #fatal, #info, #logerr, #logger, #logger=, #warn

Methods included from Util

#alive?, append_features, #btrace, #columnize, #defval, #emsg, #erreq, #errmsg, #escape, #escape!, #exec, export, #fork, #getopt, #hashify, #hms, #host, #hostname, #klass, #maim, #mcp, #realpath, #stamptime, #system, #timestamp, #tmpnam, #uncache, #which_ruby

Constructor Details

This class inherits a constructor from RQ::MainHelper

Instance Method Details

#snapshot ⇒ Object

–{{{



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# File 'lib/rq/snapshotter.rb', line 20

def snapshot 
#--{{{
  set_q
  qtmp = @argv.shift
  raise "<#{ qtmp }> exists" if qtmp and test(?e, qtmp)
  qss = @q.snapshot qtmp, @options['retries']
  #info{ "created q snapshot <#{ qtmp }>" }

  puts '---'
  puts "q: #{ qss.path }"
  puts "db: #{ qss.db.path }"
  puts "schema: #{ qss.db.schema }"
  puts "lock: #{ qss.db.lockfile }"
#--}}}
end