Creating a Gateway Response¶
A gateway response is displayed if APIG fails to process an API request. APIG provides a set of default responses and also allows you to create responses with custom status codes and content. The response content must be in JSON format.
For example, the content of a default gateway response is as follows:
{"error_code": "$context.error.code", "error_msg": "$context.error.message", "request_id": "$context.requestId"}
You can add a response with the following content:
{"errorcode": "$context.error.code", "errormsg": "$context.error.message", "requestid": "$context.requestId","apiId":"$context.apiId"}
You can add more fields to or delete existing fields from the JSON body.
Note
You can create a maximum of four gateway responses for each group.
A maximum of 10 response headers can be customized. The key of a response header can contain 1 to 128 characters, including digits, letters, and underscores (_). The value can reference runtime variables (see Context Variables), but cannot contain double brackets ([[ or ]]).
The type of a default or custom response cannot be modified, but the status code and content of the response can.
The type of a gateway response cannot be changed. For details, see Response Types.
Gateway responses can contain the API gateway context variables (starting with $context). For details, see Context Variables.
Procedure¶
Go to the APIG console.
Select a dedicated gateway at the top of the navigation pane.
Choose API Management > API Groups.
Click a group name.
Click the Group Information tab.
In the Gateway Responses area, create or modify gateway responses.
To cancel modifications to a default response, click Restore Defaults in the upper right.
Response Types¶
The following table lists the response types supported by APIG. You can define status codes to meet your service requirements.
Response Name | Default Status Code | Description |
|---|---|---|
Access Denied | 403 | Access denied. For example, the access control policy is triggered or an attack is detected. |
Authorizer Configuration Error | 500 | A custom authorizer error has occurred. For example, communication failed or an error response was returned. |
Authorizer Failed | 500 | The custom authorization failed. |
Incorrect Identity Source | 401 | The identity source of the custom authorizer is missing or invalid. |
Third-Party Configuration Error | 500 | A third-party authorizer error has occurred. For example, communication failed or an error response was returned. |
Third-Party Authorizer Failure | 401 | The third-party authorizer returns an authentication failure. |
Incorrect Third-Party Identity Source | 401 | The identity source of the third-party authorizer is missing. |
Authentication Failure | 401 | IAM or app authentication failed. |
Identity Source Not Found | 401 | No identity source has been specified. |
Backend Timeout | 504 | Communication with the backend service timed out. |
Backend Unavailable | 502 | The backend service is unavailable due to communication error. |
Default 4XX |
| Another 4XX error occurred. |
Default 5XX |
| Another 5XX error occurred. |
No API Found | 404 | No API is found. |
Incorrect Request Parameters | 400 | The request parameters are incorrect or the HTTP method is not supported. |
Request Throttled | 429 | The request was rejected due to request throttling. |
Unauthorized Credential | 401 | The credential you are using has not been authorized to call the API. |
Context Variables¶
Variable | Description |
|---|---|
$context.apiId | API ID. |
$context.apiName | API name. |
$context.appId | ID of the credential that calls the API. |
$context.appName | Name of the credential that calls the API. |
$context.requestId | Request ID generated when the API is called. |
$context.stage | Deployment environment in which the API is called. |
$context.sourceIp | Source IP address of the API caller. |
$context.reqPath | API request path, excluding the query string. |
$context.reqUri | API request path, including the query string. |
$context.reqMethod | Request method. |
$context.authorizer.frontend.property | Values of the specified attribute-value pairs mapped to the context in the frontend custom authorizer response |
$context.authorizer.backend.property | Values of the specified attribute-value pairs mapped to the context in the backend custom authorizer response |
$context.error.message | Error message. |
$context.error.code | Error code. |
$context.error.type | Error type. |