class Puppet::Util::Lockfile

This class provides a simple API for managing a lock file whose contents are an (optional) String. In addition to querying the basic state (locked?) of the lock, managing the lock (lock, unlock), the contents can be retrieved at any time while the lock is held (lock_data). This can be used to store pids, messages, etc.

@see Puppet::Util::JsonLockfile

Attributes

file_path[R]

Public Instance Methods

lock(lock_data = nil) click to toggle source

@return [boolean] true if lock is successfully acquired, false otherwise.

# File lib/puppet/util/lockfile.rb, line 25
def lock(lock_data = nil)
  begin
    Puppet::FileSystem.exclusive_create(@file_path, nil) do |fd|
      fd.print(lock_data)
    end
    true
  rescue Errno::EEXIST
    false
  end
end

lock_data() click to toggle source

Retrieve the (optional) lock data that was specified at the time the file

was locked.

@return [String] the data object.

# File lib/puppet/util/lockfile.rb, line 53
def lock_data
  return File.read(@file_path) if file_locked?
end

locked?() click to toggle source

# File lib/puppet/util/lockfile.rb, line 45
def locked?
  # delegate logic to a more explicit private method
  file_locked?
end

unlock() click to toggle source

# File lib/puppet/util/lockfile.rb, line 36
def unlock
  if locked?
    Puppet::FileSystem.unlink(@file_path)
    true
  else
    false
  end
end

Public Class Methods

new(file_path) click to toggle source

# File lib/puppet/util/lockfile.rb, line 12
def initialize(file_path)
  @file_path = file_path
end