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DecoratorFactory class

Base factory class for decorator functions

Signature:

export declare class DecoratorFactory<T, // Type of the metadata spec for individual class/method/property/parameter
M extends T | MetadataMap<T> | MetadataMap<T[]>, // Type of the metadata
D extends DecoratorType>

Example

function classDecorator(spec: MySpec): ClassDecorator {
  return ClassDecoratorFactory.createDecorator('my-key', spec);
}

or

function classDecorator(spec: MySpec): ClassDecorator {
  const factory: ClassDecoratorFactory<MySpec>('my-key', spec);
  return factory.create();
}

These functions above declare @classDecorator that can be used as follows:

@classDecorator({x: 1})
class MyController {}

Constructors

Constructor Modifiers Description
[(constructor)(key, spec, options)](/doc/en/lb4/apidocs.metadata.decoratorfactory._constructor_.html) Construct a new class decorator factory

Properties

Property Modifiers Type Description
[decoratorName](/doc/en/lb4/apidocs.metadata.decoratorfactory.decoratorname.html) `protected` string
[key](/doc/en/lb4/apidocs.metadata.decoratorfactory.key.html) `protected` string
[options](/doc/en/lb4/apidocs.metadata.decoratorfactory.options.html) `protected` [DecoratorOptions](/doc/en/lb4/apidocs.metadata.decoratoroptions.html)
[spec](/doc/en/lb4/apidocs.metadata.decoratorfactory.spec.html) `protected` T
[TARGET](/doc/en/lb4/apidocs.metadata.decoratorfactory.target.html) `static` string A constant to reference the target of a decoration

Methods

Method Modifiers Description
[\_createDecorator(key, spec, options)](/doc/en/lb4/apidocs.metadata.decoratorfactory._createdecorator.html) `protected` `static` Create a decorator function
[allowInheritance()](/doc/en/lb4/apidocs.metadata.decoratorfactory.allowinheritance.html) `protected`
[cloneDeep(val)](/doc/en/lb4/apidocs.metadata.decoratorfactory.clonedeep.html) `static`
[create()](/doc/en/lb4/apidocs.metadata.decoratorfactory.create.html) Create a decorator function of the given type. Each sub class MUST implement this method.
[decorate(target, member, descriptorOrIndex)](/doc/en/lb4/apidocs.metadata.decoratorfactory.decorate.html) `protected` Base implementation of the decorator function
[duplicateDecorationError(target, member, descriptorOrIndex)](/doc/en/lb4/apidocs.metadata.decoratorfactory.duplicatedecorationerror.html) `protected` Create an error to report if the decorator is applied to the target more than once
[getNumberOfParameters(target, member)](/doc/en/lb4/apidocs.metadata.decoratorfactory.getnumberofparameters.html) `static` Get the number of parameters for a given constructor or method
[getTarget(spec)](/doc/en/lb4/apidocs.metadata.decoratorfactory.gettarget.html) Get the optional decoration target of a given spec
[getTargetName(target, member, descriptorOrIndex)](/doc/en/lb4/apidocs.metadata.decoratorfactory.gettargetname.html) `static` Get the qualified name of a decoration target.
[inherit(inheritedMetadata)](/doc/en/lb4/apidocs.metadata.decoratorfactory.inherit.html) `protected` Inherit metadata from base classes. By default, this method merges base metadata into the spec if `allowInheritance` is set to `true`. To customize the behavior, this method can be overridden by sub classes.
[mergeWithInherited(inheritedMetadata, target, member, descriptorOrIndex)](/doc/en/lb4/apidocs.metadata.decoratorfactory.mergewithinherited.html) `protected` This method is called by the default implementation of the decorator function to merge the spec argument from the decoration with the inherited metadata for a class, all properties, all methods, or all method parameters that are decorated by this decorator. It MUST be overridden by subclasses to process inherited metadata.
[mergeWithOwn(ownMetadata, target, member, descriptorOrIndex)](/doc/en/lb4/apidocs.metadata.decoratorfactory.mergewithown.html) `protected` This method is called by the default implementation of the decorator function to merge the spec argument from the decoration with the own metadata for a class, all properties, all methods, or all method parameters that are decorated by this decorator. It MUST be overridden by subclasses to process own metadata.
[withTarget(spec, target)](/doc/en/lb4/apidocs.metadata.decoratorfactory.withtarget.html) Set a reference to the target class or prototype for a given spec if it's an object