class Vagrant::Config::VersionBase

This is the base class for any configuration versions, and includes the stub methods that configuration versions must implement. Vagrant supports configuration versioning so that backwards compatibility can be maintained for past Vagrantfiles while newer configurations are added. Vagrant only introduces new configuration versions for major versions of Vagrant.

Public Class Methods

finalize(obj) click to toggle source

This is called just before configuration loading is complete of a potentially completely-merged value to perform final touch-ups to the configuration, if required.

This is an optional method to implement. The default implementation will simply return the same object.

This will ONLY be called if this is the version that is being used. In the case that an ‘upgrade` is called, this will never be called.

@param [Object] obj Final configuration object. @param [Object] Finalized configuration object.

# File lib/vagrant/config/version_base.rb, line 32
def self.finalize(obj)
  obj
end
init() click to toggle source

Returns an empty configuration object. This can be any kind of object, since it is treated as an opaque value on the other side, used only for things like calling into {merge}.

@return [Object]

# File lib/vagrant/config/version_base.rb, line 15
def self.init
  raise NotImplementedError
end
load(proc) click to toggle source

Loads the configuration for the given proc and returns a configuration object. The return value is treated as an opaque object, so it can be anything you’d like. The return value is the object that is passed into methods like {merge}, so it should be something you expect.

@param [Proc] proc The proc that is to be configured. @return [Object]

# File lib/vagrant/config/version_base.rb, line 43
def self.load(proc)
  raise NotImplementedError
end
merge(old, new) click to toggle source

Merges two configuration objects, returning the merged object. The values of ‘old` and `new` are the opaque objects returned by {load} or {init}.

Once again, the return object is treated as an opaque value by the Vagrant configuration loader, so it can be anything you’d like.

@param [Object] old Old configuration object. @param [Object] new New configuration object. @return [Object] The merged configuration object.

# File lib/vagrant/config/version_base.rb, line 57
def self.merge(old, new)
  raise NotImplementedError
end
upgrade(old) click to toggle source

This is called if a previous version of configuration needs to be upgraded to this version. Each version of configuration should know how to upgrade the version immediately prior to it. This should be a best effort upgrade that makes many assumptions. The goal is for this to work in almost every case, but perhaps with some warnings. The return value for this is a 3-tuple: ‘[object, warnings, errors]`, where `object` is the upgraded configuration object, `warnings` is an array of warning messages, and `errors` is an array of error messages.

@param [Object] old The version of the configuration object just

prior to this one.

@return [Array] The 3-tuple result. Please see the above documentation

for more information on the exact structure of this object.
# File lib/vagrant/config/version_base.rb, line 75
def self.upgrade(old)
  raise NotImplementedError
end