Helper class providing Nest reflection capabilities.
class Reflector {
static createDecorator<TParam, TTransformed = TParam>(options: CreateDecoratorOptions<TParam, TTransformed> = {}): ReflectableDecorator<TParam, TTransformed>
get<TResult = any, TKey = any>(metadataKeyOrDecorator: TKey, target: any): TResult
getAll<TResult extends any[] = any[], TKey = any>(metadataKeyOrDecorator: TKey, targets: any[]): TResult
getAllAndMerge<TResult extends any[] | object = any[], TKey = any>(metadataKeyOrDecorator: TKey, targets: any[]): TResult
getAllAndOverride<TResult = any, TKey = any>(metadataKeyOrDecorator: TKey, targets: any[]): TResult | undefined
}
Static methods
createDecorator()
|
|---|
Creates a decorator that can be used to decorate classes and methods with metadata.
Can be used as a strongly-typed alternative to @SetMetadata.
static createDecorator<TParam>(options?: CreateDecoratorOptions<TParam, TParam>): ReflectableDecorator<TParam>
Parameters
Returns
ReflectableDecorator<TParam> A decorator function.
|
static createDecorator<TParam, TTransformed>(options: CreateDecoratorWithTransformOptions<TParam, TTransformed>): ReflectableDecorator<TParam, TTransformed>
Parameters
| Option |
Type |
Description |
options
|
CreateDecoratorWithTransformOptions |
|
Returns
ReflectableDecorator<TParam, TTransformed>
|
Methods
get()
|
|---|
|
Retrieve metadata for a specified key or decorator for a specified target.
|
Retrieve metadata for a reflectable decorator for a specified target.
get<T extends ReflectableDecorator<any>>(decorator: T, target: any): T extends ReflectableDecorator<any, infer R> ? R : unknown
Parameters
| Option |
Type |
Description |
decorator
|
T |
reflectable decorator created through Reflector.createDecorator
|
target
|
any |
context (decorated object) to retrieve metadata from
|
Examples
`const roles = this.reflector.get('roles', context.getHandler());`
Returns
T extends ReflectableDecorator<any, infer R> ? R : unknown
|
Retrieve metadata for a specified key for a specified target.
get<TResult = any, TKey = any>(metadataKey: TKey, target: any): TResult
Parameters
| Option |
Type |
Description |
metadataKey
|
TKey |
lookup key for metadata to retrieve
|
target
|
any |
context (decorated object) to retrieve metadata from
|
Examples
`const roles = this.reflector.get('roles', context.getHandler());`
Returns
TResult
|
getAll()
|
|---|
|
Retrieve metadata for a specified key or decorator for a specified set of targets.
|
Retrieve metadata for a specified decorator for a specified set of targets.
getAll<TParam = any, TTransformed = TParam>(decorator: ReflectableDecorator<TParam, TTransformed>, targets: any[]): TTransformed extends Array<any> ? TTransformed : TTransformed[]
Parameters
| Option |
Type |
Description |
decorator
|
ReflectableDecorator |
lookup decorator for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TTransformed extends Array<any> ? TTransformed : TTransformed[]
|
Retrieve metadata for a specified key for a specified set of targets.
getAll<TResult extends any[] = any[], TKey = any>(metadataKey: TKey, targets: any[]): TResult
Parameters
| Option |
Type |
Description |
metadataKey
|
TKey |
lookup key for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TResult
|
getAllAndMerge()
|
|---|
|
Retrieve metadata for a specified key or decorator for a specified set of targets and merge results.
|
Retrieve metadata for a specified decorator for a specified set of targets and merge results.
getAllAndMerge<TParam = any, TTransformed = TParam>(decorator: ReflectableDecorator<TParam, TTransformed>, targets: any[]): TTransformed extends Array<any> ? TTransformed : TTransformed extends object ? TTransformed : TTransformed[]
Parameters
| Option |
Type |
Description |
decorator
|
ReflectableDecorator |
lookup decorator for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TTransformed extends Array<any> ? TTransformed : TTransformed extends object ? TTransformed : TTransformed[]
|
Retrieve metadata for a specified key for a specified set of targets and merge results.
getAllAndMerge<TResult extends any[] | object = any[], TKey = any>(metadataKey: TKey, targets: any[]): TResult
Parameters
| Option |
Type |
Description |
metadataKey
|
TKey |
lookup key for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TResult
|
getAllAndOverride()
|
|---|
|
Retrieve metadata for a specified key or decorator for a specified set of targets and return a first not undefined value.
|
Retrieve metadata for a specified decorator for a specified set of targets and return a first not undefined value.
getAllAndOverride<TParam = any, TTransformed = TParam>(decorator: ReflectableDecorator<TParam, TTransformed>, targets: any[]): TTransformed
Parameters
| Option |
Type |
Description |
decorator
|
ReflectableDecorator |
lookup decorator for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TTransformed
|
Retrieve metadata for a specified key for a specified set of targets and return a first not undefined value.
getAllAndOverride<TResult = any, TKey = any>(metadataKey: TKey, targets: any[]): TResult
Parameters
| Option |
Type |
Description |
metadataKey
|
TKey |
lookup key for metadata to retrieve
|
targets
|
any[] |
context (decorated objects) to retrieve metadata from
|
Returns
TResult
|
