Class: Vagrant::Plugin::V2::Config
- Inherits:
-
Object
- Object
- Vagrant::Plugin::V2::Config
- Defined in:
- lib/vagrant/plugin/v2/config.rb
Overview
This is the base class for a configuration key defined for V2. Any configuration key plugins for V2 should inherit from this class.
Constant Summary collapse
- UNSET_VALUE =
This constant represents an unset value. This is useful so it is possible to know the difference between a configuration value that was never set, and a value that is nil (explicitly). Best practice is to initialize all variables to this value, then the #merge method below will "just work" in many cases.
Object.new
Instance Method Summary collapse
-
#_detected_errors ⇒ Array<String>
This returns any automatically detected errors.
-
#_finalize! ⇒ Object
An internal finalize call that no subclass should override.
-
#finalize! ⇒ Object
This is called as a last-minute hook that allows the configuration object to finalize itself before it will be put into use.
-
#instance_variables_hash ⇒ Object
Returns the instance variables as a hash of key-value pairs.
-
#merge(other) ⇒ Object
Merge another configuration object into this one.
-
#method_missing(name, *args, &block) ⇒ Object
Capture all bad configuration calls and save them for an error message later during validation.
-
#set_options(options) ⇒ Object
Allows setting options from a hash.
-
#to_json(*a) ⇒ Object
Converts this configuration object to JSON.
-
#to_s ⇒ Object
A default to_s implementation.
-
#validate(machine) ⇒ Hash
Called after the configuration is finalized and loaded to validate this object.
Dynamic Method Handling
This class handles dynamic methods through the method_missing method
#method_missing(name, *args, &block) ⇒ Object
Capture all bad configuration calls and save them for an error message later during validation.
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# File 'lib/vagrant/plugin/v2/config.rb', line 72 def method_missing(name, *args, &block) return super if @__finalized name = name.to_s name = name[0...-1] if name.end_with?("=") @__invalid_methods ||= Set.new @__invalid_methods.add(name) # Return the dummy object so that anything else works ::Vagrant::Config::V2::DummyConfig.new end |
Instance Method Details
#_detected_errors ⇒ Array<String>
This returns any automatically detected errors.
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# File 'lib/vagrant/plugin/v2/config.rb', line 130 def _detected_errors return [] if !@__invalid_methods || @__invalid_methods.empty? return [I18n.t("vagrant.config.common.bad_field", fields: @__invalid_methods.to_a.sort.join(", "))] end |
#_finalize! ⇒ Object
An internal finalize call that no subclass should override.
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# File 'lib/vagrant/plugin/v2/config.rb', line 137 def _finalize! @__finalized = true end |
#finalize! ⇒ Object
This is called as a last-minute hook that allows the configuration object to finalize itself before it will be put into use. This is a useful place to do some defaults in the case the user didn't configure something or so on.
An example of where this sort of thing is used or has been used: the "vm" configuration key uses this to make sure that at least one sub-VM has been defined: the default VM.
The configuration object is expected to mutate itself.
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# File 'lib/vagrant/plugin/v2/config.rb', line 27 def finalize! # Default implementation is to do nothing. end |
#instance_variables_hash ⇒ Object
Returns the instance variables as a hash of key-value pairs.
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# File 'lib/vagrant/plugin/v2/config.rb', line 110 def instance_variables_hash instance_variables.inject({}) do |acc, iv| acc[iv.to_s[1..-1]] = instance_variable_get(iv) acc end end |
#merge(other) ⇒ Object
Merge another configuration object into this one. This assumes that the other object is the same class as this one. This should not mutate this object, but instead should return a new, merged object.
The default implementation will simply iterate over the instance variables and merge them together, with this object overriding any conflicting instance variables of the older object. Instance variables starting with "__" (double underscores) will be ignored. This lets you set some sort of instance-specific state on your configuration keys without them being merged together later.
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# File 'lib/vagrant/plugin/v2/config.rb', line 45 def merge(other) result = self.class.new # Set all of our instance variables on the new class [self, other].each do |obj| obj.instance_variables.each do |key| # Ignore keys that start with a double underscore. This allows # configuration classes to still hold around internal state # that isn't propagated. if !key.to_s.start_with?("@__") # Don't set the value if it is the unset value, either. value = obj.instance_variable_get(key) result.instance_variable_set(key, value) if value != UNSET_VALUE end end end # Persist through the set of invalid methods this_invalid = @__invalid_methods || Set.new other_invalid = other.instance_variable_get(:"@__invalid_methods") || Set.new result.instance_variable_set(:"@__invalid_methods", this_invalid + other_invalid) result end |
#set_options(options) ⇒ Object
Allows setting options from a hash. By default this simply calls
the #{key}=
method on the config class with the value, which is
the expected behavior most of the time.
This is expected to mutate itself.
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# File 'lib/vagrant/plugin/v2/config.rb', line 93 def () .each do |key, value| send("#{key}=", value) end end |
#to_json(*a) ⇒ Object
Converts this configuration object to JSON.
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# File 'lib/vagrant/plugin/v2/config.rb', line 100 def to_json(*a) instance_variables_hash.to_json(*a) end |
#to_s ⇒ Object
A default to_s implementation.
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# File 'lib/vagrant/plugin/v2/config.rb', line 105 def to_s self.class.to_s end |
#validate(machine) ⇒ Hash
Called after the configuration is finalized and loaded to validate this object.
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# File 'lib/vagrant/plugin/v2/config.rb', line 123 def validate(machine) return { self.to_s => _detected_errors } end |