# RequestAuthorizer

Request-based lambda authorizer that recognizes the caller's identity via request parameters, such as headers, paths, query strings, stage variables, or context variables.

Based on the request, authorization is performed by a lambda function.

Extends: Construct › Resource › Authorizer › RequestAuthorizer
Implements: IResource, IAuthorizer, IEnvironmentAware, IConstruct, IDependable

- CloudFormation: [`AWS::ApiGateway::Authorizer`](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-resource-apigateway-authorizer.html)
- L1 type: [`CfnAuthorizer`](/cdk/api/v2/docs/aws-cdk-lib.aws_apigateway.CfnAuthorizer.html)
- Source: [`aws-apigateway/lib/authorizers/lambda.ts`](https://github.com/aws/aws-cdk/blob/v2.273.0/packages/aws-cdk-lib/aws-apigateway/lib/authorizers/lambda.ts#L275)
- Type last changed: v2.196.0 · 16 May 2025

## Example

```ts
declare const authFn: lambda.Function;
declare const books: apigateway.Resource;

const auth = new apigateway.RequestAuthorizer(this, 'booksAuthorizer', {
  handler: authFn,
  identitySources: [apigateway.IdentitySource.header('Authorization')]
});

books.addMethod('GET', new apigateway.HttpIntegration('http://amazon.com'), {
  authorizer: auth
});
```

## Initializer

```ts
new RequestAuthorizer(scope: Construct, id: string, props: RequestAuthorizerProps)
```

## Construct Props

- `assumeRole`: [IRole](/cdk/api/v2/docs/aws-cdk-lib.aws_iam.IRole.html) = A resource policy is added to the Lambda function allowing apigateway.amazonaws.com to invoke the function. — An optional IAM role for APIGateway to assume before calling the Lambda-based authorizer.

  The IAM role must be
  assumable by 'apigateway.amazonaws.com'.

  **Default:** A resource policy is added to the Lambda function allowing apigateway.amazonaws.com to invoke the function.

- `authorizerName`: string = the unique construct ID — An optional human friendly name for the authorizer.

  Note that, this is not the primary identifier of the authorizer.

- `handler`: [IFunction](/cdk/api/v2/docs/aws-cdk-lib.aws_lambda.IFunction.html) (required) — The handler for the authorizer lambda function.

  The handler must follow a very specific protocol on the input it receives
  and the output it needs to produce.  API Gateway has documented the
  handler's [input specification](https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-lambda-authorizer-input.html)
  and [output specification](https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-lambda-authorizer-output.html).

- `identitySources`: string[] (required) — An array of request header mapping expressions for identities.

  Supported parameter types are
  Header, Query String, Stage Variable, and Context. For instance, extracting an authorization
  token from a header would use the identity source `IdentitySource.header('Authorization')`.

  Note: API Gateway uses the specified identity sources as the request authorizer caching key. When caching is
  enabled, API Gateway calls the authorizer's Lambda function only after successfully verifying that all the
  specified identity sources are present at runtime. If a specified identify source is missing, null, or empty,
  API Gateway returns a 401 Unauthorized response without calling the authorizer Lambda function.

- `resultsCacheTtl`: [Duration](/cdk/api/v2/docs/aws-cdk-lib.Duration.html) = Duration.minutes(5) — How long APIGateway should cache the results.

  Max 1 hour.
  Disable caching by setting this to 0.

## Properties

- `authorizationType`: [AuthorizationType](/cdk/api/v2/docs/aws-cdk-lib.aws_apigateway.AuthorizationType.html) — The authorization type of this authorizer.

- `authorizerArn`: string (required) — The ARN of the authorizer to be used in permission policies, such as IAM and resource-based grants.

- `authorizerId`: string (required) — The id of the authorizer.

- `env`: [ResourceEnvironment](/cdk/api/v2/docs/aws-cdk-lib.interfaces.ResourceEnvironment.html) (required) — The environment this resource belongs to.

  For resources that are created and managed in a Stack (those created by
  creating new class instances like `new Role()`, `new Bucket()`, etc.), this
  is always the same as the environment of the stack they belong to.

  For referenced resources (those obtained from referencing methods like
  `Role.fromRoleArn()`, `Bucket.fromBucketName()`, etc.), they might be
  different than the stack they were imported into.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) (required) — The tree node.

- `PROPERTY_INJECTION_ID`: string (required) (static) — Uniquely identifies this class.

- `stack`: [Stack](/cdk/api/v2/docs/aws-cdk-lib.Stack.html) (required) — The stack in which this resource is defined.

## Methods

- `applyCrossStackReferenceStrength(strength: ReferenceStrength): void` — Override the cross-stack reference strength for this resource.

  When set, any cross-stack reference to this resource will use the specified
  mechanism instead of the global default determined by the
  `@aws-cdk/core:defaultCrossStackReferences` context key. This is useful for
  selectively weakening specific references to avoid the "deadly embrace" problem
  without changing the app-wide default.

  **Parameters**

  - `strength` — - The reference strength to use for this resource.

- `applyRemovalPolicy(policy: RemovalPolicy): void` — Apply the given removal policy to this resource.

  The Removal Policy controls what happens to this resource when it stops
  being managed by CloudFormation, either because you've removed it from the
  CDK application or because you've made a change that requires the resource
  to be replaced.

  The resource can be deleted (`RemovalPolicy.DESTROY`), or left in your AWS
  account for data recovery and cleanup later (`RemovalPolicy.RETAIN`).

- `isAuthorizer(x: any): boolean` (static) — Return whether the given object is an Authorizer.

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  Use this method instead of `instanceof` to properly detect `Construct`
  instances, even when the construct library is symlinked.

  Explanation: in JavaScript, multiple copies of the `constructs` library on
  disk are seen as independent, completely different libraries. As a
  consequence, the class `Construct` in each copy of the `constructs` library
  is seen as a different class, and an instance of one class will not test as
  `instanceof` the other class. `npm install` will not create installations
  like this, but users may manually symlink construct libraries together or
  use a monorepo tool: in those cases, multiple copies of the `constructs`
  library can be accidentally installed, and `instanceof` will behave
  unpredictably. It is safest to avoid using `instanceof`, and using
  this type-testing method instead.

  **Parameters**

  - `x` — Any object.

  **Returns:** true if `x` is an object created from a class which extends `Construct`.

- `isOwnedResource(construct: IConstruct): boolean` (static) — Returns true if the construct was created by CDK, and false otherwise.

- `isResource(construct: IConstruct): boolean` (static) — Check whether the given construct is a Resource.

- `toString(): string` — Returns a string representation of this construct.

- `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct.

  Mixins are applied in order. The list of constructs is captured at the
  start of the call, so constructs added by a mixin will not be visited.
  Use multiple `with()` calls if subsequent mixins should apply to added
  constructs.