Class: Backup::Compressor::Gzip

Inherits:
Base
  • Object
show all
Extended by:
Utilities::Helpers
Defined in:
lib/backup/compressor/gzip.rb

Defined Under Namespace

Classes: Error

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Base

#compress_with

Methods included from Backup::Config::Helpers

included

Constructor Details

#initialize(&block) ⇒ Gzip

Creates a new instance of Backup::Compressor::Gzip



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# File 'lib/backup/compressor/gzip.rb', line 44

def initialize(&block)
  load_defaults!

  @level ||= false
  @rsyncable ||= false

  instance_eval(&block) if block_given?

  @cmd = "#{ utility(:gzip) }#{ options }"
  @ext = '.gz'
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class Backup::Config::Helpers

Instance Attribute Details

#level ⇒ Object

Specify the level of compression to use.

Values should be a single digit from 1 to 9. Note that setting the level to either extreme may or may not give the desired result. Be sure to check the documentation for the compressor being used.

The default level is 6.



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# File 'lib/backup/compressor/gzip.rb', line 18

def level
  @level
end

#rsyncable ⇒ Object

Use the --rsyncable option with gzip.

This option directs gzip to compress data using an algorithm that allows rsync to efficiently detect changes. This is especially useful when used to compress Archive or Database backups that will be stored using Backup’s RSync Storage option.

The --rsyncable option is only available on patched versions of gzip. While most distributions apply this patch, this option may not be available on your system. If it’s not available, Backup will log a warning and continue to use the compressor without this option.



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# File 'lib/backup/compressor/gzip.rb', line 32

def rsyncable
  @rsyncable
end

Class Method Details

.has_rsyncable? ⇒ Boolean

Determine if --rsyncable is supported and cache the result.

Returns:

  • (Boolean) 


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# File 'lib/backup/compressor/gzip.rb', line 36

def self.has_rsyncable?
  return @has_rsyncable unless @has_rsyncable.nil?
  cmd = "#{ utility(:gzip) } --rsyncable --version >/dev/null 2>&1; echo $?"
  @has_rsyncable = %x[#{ cmd }].chomp == '0'
end