feat: Release inferred spans for function URLs

event_samples/lambda-function-urls.json

@@ -0,0 +1,46 @@
+{
+  "version": "2.0",
+  "routeKey": "$default",
+  "rawPath": "/",
+  "rawQueryString": "",
+  "headers": {
+    "sec-fetch-mode": "navigate",
+    "sec-fetch-site": "none",
+    "accept-language": "en-US,en;q=0.9",
+    "x-forwarded-proto": "https",
+    "x-forwarded-port": "443",
+    "x-forwarded-for": "71.195.30.42",
+    "sec-fetch-user": "?1",
+    "pragma": "no-cache",
+    "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
+    "sec-ch-ua": "\"Google Chrome\";v=\"95\", \"Chromium\";v=\"95\", \";Not A Brand\";v=\"99\"",
+    "sec-ch-ua-mobile": "?0",
+    "x-amzn-trace-id": "Root=1-61953929-1ec00c3011062a48477b169e",
+    "sec-ch-ua-platform": "\"macOS\"",
+    "host": "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com",
+    "upgrade-insecure-requests": "1",
+    "cache-control": "no-cache",
+    "accept-encoding": "gzip, deflate, br",
+    "sec-fetch-dest": "document",
+    "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36"
+  },
+  "requestContext": {
+    "accountId": "601427279990",
+    "apiId": "a8hyhsshac",
+    "domainName": "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com",
+    "domainPrefix": "a8hyhsshac",
+    "http": {
+      "method": "GET",
+      "path": "/",
+      "protocol": "HTTP/1.1",
+      "sourceIp": "71.195.30.42",
+      "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36"
+    },
+    "requestId": "ec4d58f8-2b8b-4ceb-a1d5-2be7bff58505",
+    "routeKey": "$default",
+    "stage": "$default",
+    "time": "17/Nov/2021:17:17:29 +0000",
+    "timeEpoch": 1637169449721
+  },
+  "isBase64Encoded": false
+}

src/trace/span-inferrer.spec.ts

@@ -10,6 +10,7 @@ const webSocketEvent = require("../../event_samples/api-gateway-wss.json");
 const apiGatewayV1 = require("../../event_samples/api-gateway-v1.json");
 const apiGatewayV2 = require("../../event_samples/api-gateway-v2.json");
 const s3Event = require("../../event_samples/s3.json");
+const functionUrlEvent = require("../../event_samples/lambda-function-urls.json");
 const mockWrapper = {
   startSpan: jest.fn(),
 };
@@ -172,6 +173,7 @@ describe("SpanInferrer", () => {
       ],
     ]);
   });
+
   it("creates an inferred span for eventbridge events", () => {
     const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
     inferrer.createInferredSpan(eventBridgeEvent, {} as any, {} as SpanContext);
@@ -190,6 +192,7 @@ describe("SpanInferrer", () => {
       },
     });
   });
+
   it("creates an inferred span for websocket events", () => {
     const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
     inferrer.createInferredSpan(webSocketEvent, {} as any, {} as SpanContext);
@@ -198,7 +201,7 @@ describe("SpanInferrer", () => {
       childOf: {},
       startTime: undefined,
       tags: {
-        _inferred_span: { synchronicity: undefined, tag_source: "self" },
+        _inferred_span: { synchronicity: "sync", tag_source: "self" },
         apiid: "08se3mvh28",
         connection_id: "MM0qReAFGjQCE-w=",
         endpoint: "$connect",
@@ -215,6 +218,7 @@ describe("SpanInferrer", () => {
       },
     });
   });
+
   it("creates an inferred span for API Gateway V1 events", () => {
     const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
     inferrer.createInferredSpan(apiGatewayV1, {} as any, {} as SpanContext);
@@ -223,7 +227,7 @@ describe("SpanInferrer", () => {
       childOf: {},
       startTime: undefined,
       tags: {
-        _inferred_span: { synchronicity: undefined, tag_source: "self" },
+        _inferred_span: { synchronicity: "sync", tag_source: "self" },
         apiid: "id",
         endpoint: "/my/path",
         "http.url": "id.execute-api.us-east-1.amazonaws.com/my/path",
@@ -240,6 +244,7 @@ describe("SpanInferrer", () => {
       },
     });
   });
+
   it("creates an inferred span for API Gateway V2 events", () => {
     const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
     inferrer.createInferredSpan(apiGatewayV2, {} as any, {} as SpanContext);
@@ -248,7 +253,7 @@ describe("SpanInferrer", () => {
       childOf: {},
       startTime: 1583817383220,
       tags: {
-        _inferred_span: { synchronicity: undefined, tag_source: "self" },
+        _inferred_span: { synchronicity: "sync", tag_source: "self" },
         apiid: "r3pmxmplak",
         endpoint: "/default/nodejs-apig-function-1G3XMPLZXVXYI",
         "http.url": "r3pmxmplak.execute-api.us-east-2.amazonaws.com/default/nodejs-apig-function-1G3XMPLZXVXYI",
@@ -265,6 +270,31 @@ describe("SpanInferrer", () => {
       },
     });
   });
+
+  it("creates an inferred span for Lambda Function URL Events", () => {
+    const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
+    inferrer.createInferredSpan(functionUrlEvent, {} as any, {} as SpanContext);
+
+    expect(mockWrapper.startSpan).toBeCalledWith("aws.lambda.url", {
+      service: "aws.lambda",
+      startTime: 1637169449721,
+      tags: {
+        _inferred_span: {
+          synchronicity: "sync",
+          tag_source: "self",
+        },
+        endpoint: "/",
+        "http.method": "GET",
+        "http.url": "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com/",
+        operation_name: "aws.lambda.url",
+        request_id: undefined,
+        "resource.name": "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com/",
+        resource_names: "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com/",
+        "span.type": "http",
+      },
+    });
+  });
+
   it("creates an inferred span for s3 events", () => {
     const inferrer = new SpanInferrer(mockWrapper as unknown as TracerWrapper);
     inferrer.createInferredSpan(s3Event, {} as any, {} as SpanContext);

src/trace/span-inferrer.ts

@@ -19,6 +19,9 @@ export class SpanInferrer {
 
   public createInferredSpan(event: any, context: Context | undefined, parentSpanContext: SpanContext | undefined): any {
     const eventSource = parseEventSource(event);
+    if (eventSource === eventSources.lambdaUrl) {
+      return this.createInferredSpanForLambdaUrl(event, context);
+    }
     if (eventSource === eventSources.apiGateway) {
       return this.createInferredSpanForApiGateway(event, context, parentSpanContext);
     }
@@ -42,10 +45,11 @@ export class SpanInferrer {
     }
   }
 
-  isApiGatewayAsync(event: any): boolean {
-    return (
-      event.headers && event.headers["X-Amz-Invocation-Type"] && event.headers["X-Amz-Invocation-Type"] === "Event"
-    );
+  isApiGatewayAsync(event: any): string {
+    if (event.headers && event.headers["X-Amz-Invocation-Type"] && event.headers["X-Amz-Invocation-Type"] === "Event") {
+      return "async";
+    }
+    return "sync";
   }
 
   createInferredSpanForApiGateway(
@@ -98,11 +102,37 @@ export class SpanInferrer {
     }
     options.startTime = event.requestContext.timeEpoch;
     const spanWrapperOptions = {
-      isAsync: this.isApiGatewayAsync(event),
+      isAsync: this.isApiGatewayAsync(event) === "async",
     };
     return new SpanWrapper(this.traceWrapper.startSpan("aws.apigateway", options), spanWrapperOptions);
   }
 
+  createInferredSpanForLambdaUrl(event: any, context: Context | undefined): any {
+    const options: SpanOptions = {};
+    const domain = event.requestContext.domainName;
+    const path = event.rawPath;
+    options.tags = {
+      operation_name: "aws.lambda.url",
+      "http.url": domain + path,
+      endpoint: path,
+      "http.method": event.requestContext.http.method,
+      resource_names: domain + path,
+      request_id: context?.awsRequestId,
+      "span.type": "http",
+      "resource.name": domain + path,
+      _inferred_span: {
+        tag_source: "self",
+        synchronicity: "sync",
+      },
+    };
+    options.service = "aws.lambda";
+    options.startTime = event.requestContext.timeEpoch;
+    const spanWrapperOptions = {
+      isAsync: false,
+    };
+    return new SpanWrapper(this.traceWrapper.startSpan("aws.lambda.url", options), spanWrapperOptions);
+  }
+
   createInferredSpanForDynamoDBStreamEvent(
     event: any,
     context: Context | undefined,

src/trace/trigger.spec.ts

@@ -30,6 +30,15 @@ describe("parseEventSource", () => {
       },
       file: "api-gateway-v2.json",
     },
+    {
+      result: {
+        "function_trigger.event_source": "lambda-function-url",
+        "http.url": "a8hyhsshac.lambda-url.eu-south-1.amazonaws.com",
+        "http.url_details.path": "/",
+        "http.method": "GET",
+      },
+      file: "lambda-function-urls.json",
+    },
     {
       result: {
         "function_trigger.event_source": "application-load-balancer",

src/trace/trigger.ts

@@ -17,6 +17,17 @@ import * as eventType from "../utils/event-type-guards";
 import { logError } from "../utils";
 import { gunzipSync } from "zlib";
 
+type LambdaURLEvent = {
+  headers: { [name: string]: string | undefined };
+  requestContext: {
+    domainName?: string | undefined;
+    http: {
+      method: string;
+      path: string;
+    };
+  };
+};
+
 function isHTTPTriggerEvent(eventSource: string | undefined) {
   return (
     eventSource === "api-gateway" ||
@@ -91,6 +102,7 @@ export enum eventSources {
   dynamoDB = "dynamodb",
   eventBridge = "eventbridge",
   kinesis = "kinesis",
+  lambdaUrl = "lambda-function-url",
   s3 = "s3",
   sns = "sns",
   sqs = "sqs",
@@ -103,14 +115,16 @@ export enum eventSources {
  * cloudwatch-events | cloudfront | dynamodb | kinesis | s3 | sns | sqs
  */
 export function parseEventSource(event: any) {
+  if (eventType.isLambdaUrlEvent(event)) {
+    return eventSources.lambdaUrl;
+  }
   if (
     eventType.isAPIGatewayEvent(event) ||
     eventType.isAPIGatewayEventV2(event) ||
     eventType.isAPIGatewayWebsocketEvent(event)
   ) {
     return eventSources.apiGateway;
   }
-
   if (eventType.isALBEvent(event)) {
     return eventSources.applicationLoadBalancer;
   }
@@ -226,7 +240,7 @@ export function parseEventSourceARN(source: string | undefined, event: any, cont
 /**
  * extractHTTPTags extracts HTTP facet tags from the triggering event
  */
-function extractHTTPTags(event: APIGatewayEvent | APIGatewayProxyEventV2 | ALBEvent) {
+function extractHTTPTags(event: APIGatewayEvent | APIGatewayProxyEventV2 | ALBEvent | LambdaURLEvent) {
   const httpTags: { [key: string]: string } = {};
 
   if (eventType.isAPIGatewayEvent(event)) {
@@ -261,6 +275,19 @@ function extractHTTPTags(event: APIGatewayEvent | APIGatewayProxyEventV2 | ALBEv
     }
     return httpTags;
   }
+
+  if (eventType.isLambdaUrlEvent(event)) {
+    const requestContext = event.requestContext;
+    if (requestContext.domainName) {
+      httpTags["http.url"] = requestContext.domainName;
+    }
+    httpTags["http.url_details.path"] = requestContext.http.path;
+    httpTags["http.method"] = requestContext.http.method;
+    if (event.headers?.Referer) {
+      httpTags["http.referer"] = event.headers.Referer;
+    }
+    return httpTags;
+  }
 }
 
 /**

src/utils/event-type-guards.ts

@@ -90,3 +90,11 @@ export function isAppSyncResolverEvent(event: any): event is AppSyncResolverEven
 export function isEventBridgeEvent(event: any): event is EventBridgeEvent<any, any> {
   return event["detail-type"] !== undefined;
 }
+
+export function isLambdaUrlEvent(event: any): boolean {
+  return (
+    event.requestContext !== undefined &&
+    event.requestContext.domainName &&
+    event.requestContext.domainName.includes("lambda-url")
+  );
+}