Understanding AWS X-Ray traces for Amazon API Gateway APIs

This section discusses AWS X-Ray trace segments, subsegments, and other trace fields for Amazon API Gateway APIs.

Before you read this section, review the following topics in the X-Ray Developer Guide:

• AWS X-Ray Console

• AWS X-Ray Segment Documents

• X-Ray Concepts

Examples of trace objects for an API Gateway API

This section discusses some of the objects you may see in a trace for an API Gateway API.

Annotations

Annotations can appear in segments and subsegments. They are used as filtering expressions in sampling rules to filter traces. For more information, see Configuring Sampling Rules in the AWS X-Ray Console.

Following is an example of an annotations object, in which an API stage is identified by the API ID and the API stage name:

"annotations": {
    "aws:api_id": "a1b2c3d4e5",
    "aws:api_stage": "dev"
}

AWS resource data

The aws object appears only in segments. Following is an example of an aws object that matches the Default sampling rule. For an in-depth explanation of sampling rules, see Configuring Sampling Rules in the AWS X-Ray Console.

"aws": {
    "xray": {
        "sampling_rule_name": "Default"
    },
    "api_gateway": {
        "account_id": "123412341234",
        "rest_api_id": "a1b2c3d4e5",
        "stage": "dev",
        "request_id": "a1b2c3d4-a1b2-a1b2-a1b2-a1b2c3d4e5f6"
    }
}

Understanding the trace

Following is a trace segment for an API Gateway stage. For a detailed explanation of the fields that make up the trace segment, see AWS X-Ray Segment Documents in the AWS X-Ray Developer Guide.

        {
            "Document": {
                "id": "a1b2c3d4a1b2c3d4",
                "name": "testxray/dev",
                "start_time": 1533928226.229,
                "end_time": 1533928226.614,
                "metadata": {
                    "default": {
                        "extended_request_id": "abcde12345abcde=",
                        "request_id": "a1b2c3d4-a1b2-a1b2-a1b2-a1b2c3d4e5f6"
                    }
                },
                "http": {
                    "request": {
                        "url": "https://example.com/dev?username=demo&message=hellofromdemo/",
                        "method": "GET",
                        "client_ip": "192.0.2.0",
                        "x_forwarded_for": true
                    },
                    "response": {
                        "status": 200,
                        "content_length": 0
                    }
                },
                "aws": {
                    "xray": {
                        "sampling_rule_name": "Default"
                    },
                    "api_gateway": {
                        "account_id": "123412341234",
                        "rest_api_id": "a1b2c3d4e5",
                        "stage": "dev",
                        "request_id": "a1b2c3d4-a1b2-a1b2-a1b2-a1b2c3d4e5f6"
                    }
                },
                "annotations": {
                    "aws:api_id": "a1b2c3d4e5",
                    "aws:api_stage": "dev"
                },
                "trace_id": "1-a1b2c3d4-a1b2c3d4a1b2c3d4a1b2c3d4",
                "origin": "AWS::ApiGateway::Stage",
                "resource_arn": "arn:aws:apigateway:us-east-1::/restapis/a1b2c3d4e5/stages/dev",
                "subsegments": [
                    {
                        "id": "abcdefgh12345678",
                        "name": "Lambda",
                        "start_time": 1533928226.233,
                        "end_time": 1533928226.6130002,
                        "http": {
                            "request": {
                                "url": "https://example.com/2015-03-31/functions/arn:aws:lambda:us-east-1:123412341234:function:xray123/invocations",
                                "method": "GET"
                            },
                            "response": {
                                "status": 200,
                                "content_length": 62
                            }
                        },
                        "aws": {
                            "function_name": "xray123",
                            "region": "us-east-1",
                            "operation": "Invoke",
                            "resource_names": [
                                "xray123"
                            ]
                        },
                        "namespace": "aws"
                    }
                ]
            },
            "Id": "a1b2c3d4a1b2c3d4"
        }