Set up a method using the API Gateway console

In the Resources pane, choose your method, and then choose the Method request tab.

In the Method request settings section, choose Edit.

For Authorization, select an available authorizer.

1. To enable open access to the method for any user, select None. This step can be skipped if the default setting has not been changed.

2. To use IAM permissions to control the client access to the method, select AWS_IAM. With this choice, only users of the IAM roles with the correct IAM policy attached are allowed to call this method.

   To create the IAM role, specify an access policy with a format like the following:

   {
     "Version": "2012-10-17",
     "Statement": [
       {
         "Effect": "Allow",
         "Action": [
           "execute-api:Invoke"
         ],
         "Resource": [
           "resource-statement"
         ]
       }
     ]
   }  

   In this access policy, resource-statement is the ARN of your method. You can find the ARN of your method by selecting the method on the Resources page. For more information about setting the IAM permissions, see Control access to a REST API with IAM permissions.

   To create the IAM role, you can adapt the instructions in the following tutorial, Create a Lambda function for Lambda non-proxy integration.

3. To use a Lambda authorizer, select a token or a request authorizer. Create the Lambda authorizer to have this choice displayed in the dropdown menu. For information on how to create a Lambda authorizer, see Use API Gateway Lambda authorizers.

4. To use an Amazon Cognito user pool, choose an available user pool under Cognito user pool authorizers. Create a user pool in Amazon Cognito and an Amazon Cognito user pool authorizer in API Gateway to have this choice displayed in the dropdown menu. For information on how to create an Amazon Cognito user pool authorizer, see Control access to REST APIs using Amazon Cognito user pools as an authorizer.

To specify request validation, select a value from the Request Validator dropdown menu. To turn off request validation, select None. For more information about each option, see Request validation for REST APIs in API Gateway.

Select API key required to require an API key. When enabled, API keys are used in usage plans to throttle client traffic.

(Optional) To assign an operation name in a Java SDK of this API, generated by API Gateway, for Operation name, enter a name. For example, for the method request of GET /pets/{petId}, the corresponding Java SDK operation name is, by default ,GetPetsPetId. This name is constructed from the method's HTTP verb (GET) and the resource path variable names (Pets and PetId). If you set the operation name as getPetById, the SDK operation name becomes GetPetById.

To add a query string parameter to the method, do the following:

1. Choose URL Query string parameters, and then choose Add query string.

2. For Name, enter the name of the query string parameter.

3. Select Required if the newly created query string parameter is to be used for request validation. For more information about the request validation, see Request validation for REST APIs in API Gateway.

4. Select Caching if the newly created query string parameter is to be used as part of a caching key. For more information about caching, see Use method or integration parameters as cache keys to index cached responses.

To remove the query string parameter, choose Remove.

To add a header parameter to the method, do the following:

1. Choose HTTP request headers, and then choose Add header.

2. For Name, enter the name of the header.

3. Select Required if the newly created header is to be used for request validation. For more information about the request validation, see Request validation for REST APIs in API Gateway.

4. Select Caching if the newly created header is to be used as part of a caching key. For more information about caching, see Use method or integration parameters as cache keys to index cached responses.

To remove the header, choose Remove.

To declare the payload format of a method request with the POST, PUT, or PATCH HTTP verb, choose Request body, and do the following:

1. Choose Add model.

2. For Content-type, enter a MIME-type (for example, application/json).

3. For Model, select a model from the dropdown menu. The currently available models for the API include the default Empty and Error models as well as any models you have created and added to the Models collection of the API. For more information about creating a model, see Data models for REST APIs.

   Note

   The model is useful to inform the client of the expected data format of a payload. It is helpful to generate a skeletal mapping template. It is important to generate a strongly typed SDK of the API in such languages as Java, C#, Objective-C, and Swift. It is only required if request validation is enabled against the payload.

Choose Save.

In the Resources pane, choose your method, and then choose the Method response tab. You might need to choose the right arrow button to show the tab.

In the Method response settings section, choose Create response.

For HTTP status code, enter an HTTP status code such as 200, 400, or 500.

When a backend-returned response does not have a corresponding method response defined, API Gateway fails to return the response to the client. Instead, it returns a 500 Internal server error error response.

Choose Add header.

For Header name, enter a name.

To return a header from the backend to the client, add the header in the method response.

Choose Add model to define a format of the method response body.

Enter the media type of the response payload for Content type and choose a model from the Models dropdown menu.

Choose Save.