@loopback/metadata

This module contains utilities to help developers implement
TypeScript decorators,
define/merge metadata, and inspect metadata.

- Reflector: Wrapper of
reflect-metadata
- Decorator factories: A set of factories for class/method/property/parameter
decorators to apply metadata to a given class and its static or instance
members.
- MetadataInspector: High level APIs to inspect a class and/or its members to
get metadata applied by decorators.

Basic Use

$3

``ts
import {ClassDecoratorFactory} from '@loopback/metadata';

export interface MyClassMetadata {
name: string;
description?: string;
}

function myClassDecorator(spec: MyClassMetadata): ClassDecorator {
return ClassDecoratorFactory.createDecorator(
'metadata-key-for-my-class-decorator',
spec,
{decoratorName: '@myClassDecorator'},
);
}
`

Alternatively, we can instantiate the factory and create a decorator:

`ts
function myClassDecorator(spec: MyClassMetadata): ClassDecorator {
const factory = new ClassDecoratorFactory(
'metadata-key-for-my-class-decorator',
spec,
);
return factory.create();
}
`

Now we can use @myClassDecorator to add metadata to a class as follows:

`ts
@myClassDecorator({name: 'my-controller'})
class MyController {}
`

$3

`ts
import {MethodDecoratorFactory} from '@loopback/metadata';

export interface MyMethodMetadata {
name: string;
description?: string;
}

function myMethodDecorator(spec: MyMethodMetadata): MethodDecorator {
return MethodDecoratorFactory.createDecorator(
'metadata-key-for-my-method-decorator',
spec,
);
}
`

Now we can use @myMethodDecorator to add metadata to a method as follows:

`ts
class MyController {
@myMethodDecorator({name: 'my-method'})
myMethod(x: string): string {
return 'Hello, ' + x;
}

@myMethodDecorator({name: 'another-method'})
anotherMethod() {}

@myMethodDecorator({name: 'my-static-method'})
static myStaticMethod() {}
}
`

$3

Instead of a single immutable object to be merged, the
MethodMultiDecoratorFactory reduced parameters into a flat array of items.
When fetching the metadata later, you will receive it as an array.

`ts
import {MethodMultiDecoratorFactory} from '@loopback/metadata';

function myMultiMethodDecorator(spec: object): MethodDecorator {
return MethodMultiDecoratorFactory.createDecorator