Fix API Gateway type guards (#165)

make apigateway type guard more specific

Author: DylanLovesCoffee

event_samples/api-gateway-v2.json

@@ -0,0 +1,46 @@
+{
+    "version": "2.0",
+    "routeKey": "ANY /nodejs-apig-function-1G3XMPLZXVXYI",
+    "rawPath": "/default/nodejs-apig-function-1G3XMPLZXVXYI",
+    "rawQueryString": "",
+    "cookies": [
+        "s_fid=7AABXMPL1AFD9BBF-0643XMPL09956DE2",
+        "regStatus=pre-register"
+    ],
+    "headers": {
+        "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
+        "accept-encoding": "gzip, deflate, br",
+        "accept-language": "en-US,en;q=0.9",
+        "content-length": "0",
+        "host": "r3pmxmplak.execute-api.us-east-2.amazonaws.com",
+        "sec-fetch-dest": "document",
+        "sec-fetch-mode": "navigate",
+        "sec-fetch-site": "cross-site",
+        "sec-fetch-user": "?1",
+        "upgrade-insecure-requests": "1",
+        "user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36",
+        "x-amzn-trace-id": "Root=1-5e6722a7-cc56xmpl46db7ae02d4da47e",
+        "x-forwarded-for": "205.255.255.176",
+        "x-forwarded-port": "443",
+        "x-forwarded-proto": "https"
+    },
+    "requestContext": {
+        "accountId": "123456789012",
+        "apiId": "r3pmxmplak",
+        "domainName": "r3pmxmplak.execute-api.us-east-2.amazonaws.com",
+        "domainPrefix": "r3pmxmplak",
+        "http": {
+            "method": "GET",
+            "path": "/default/nodejs-apig-function-1G3XMPLZXVXYI",
+            "protocol": "HTTP/1.1",
+            "sourceIp": "205.255.255.176",
+            "userAgent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36"
+        },
+        "requestId": "JKJaXmPLvHcESHA=",
+        "routeKey": "ANY /nodejs-apig-function-1G3XMPLZXVXYI",
+        "stage": "default",
+        "time": "10/Mar/2020:05:16:23 +0000",
+        "timeEpoch": 1583817383220
+    },
+    "isBase64Encoded": true
+}

event_samples/api-gateway.json

@@ -21,3 +21,4 @@ export const xraySubsegmentNamespace = "datadog";
 export const xrayTraceEnvVar = "_X_AMZN_TRACE_ID";
 export const awsXrayDaemonAddressEnvVar = "AWS_XRAY_DAEMON_ADDRESS";
 export const ddtraceVersion = "X.X.X";
+export const apiGatewayEventV2 = "2.0";

src/trace/constants.ts

@@ -23,12 +23,12 @@ describe("parseEventSource", () => {
     {
       result: {
         "function_trigger.event_source": "api-gateway",
-        "function_trigger.event_source_arn": "arn:aws:apigateway:us-east-1::/restapis/1234567890/stages/prod",
-        "http.url": "70ixmpl4fl.execute-api.us-east-2.amazonaws.com",
-        "http.url_details.path": "/prod/path/to/resource",
-        "http.method": "POST",
+        "function_trigger.event_source_arn": "arn:aws:apigateway:us-east-1::/restapis/r3pmxmplak/stages/default",
+        "http.url": "r3pmxmplak.execute-api.us-east-2.amazonaws.com",
+        "http.url_details.path": "/default/nodejs-apig-function-1G3XMPLZXVXYI",
+        "http.method": "GET",
       },
-      file: "api-gateway.json",
+      file: "api-gateway-v2.json",
     },
     {
       result: {
@@ -146,7 +146,7 @@ describe("parseEventSource", () => {
       for (let response of responses) {
         const statusCode = extractHTTPStatusCodeTag(triggerTags, response.responseBody);
         // We should always return a status code for API Gateway and ALB
-        if (["api-gateway-v1.json", "api-gateway.json", "application-load-balancer.json"].includes(event.file)) {
+        if (["api-gateway-v1.json", "api-gateway-v2.json", "application-load-balancer.json"].includes(event.file)) {
           expect(statusCode).toEqual(response.expectedStatusCode);
         } else {
           expect(statusCode).toBeUndefined();

src/trace/trigger.spec.ts

@@ -202,7 +202,7 @@ function extractHTTPTags(event: APIGatewayEvent | APIGatewayProxyEventV2 | ALBEv
     }
     httpTags["http.url_details.path"] = requestContext.path;
     httpTags["http.method"] = requestContext.httpMethod;
-    if (event.headers.Referer) {
+    if (event.headers?.Referer) {
       httpTags["http.referer"] = event.headers.Referer;
     }
     return httpTags;
@@ -213,7 +213,7 @@ function extractHTTPTags(event: APIGatewayEvent | APIGatewayProxyEventV2 | ALBEv
     httpTags["http.url"] = requestContext.domainName;
     httpTags["http.url_details.path"] = requestContext.http.path;
     httpTags["http.method"] = requestContext.http.method;
-    if (event.headers.Referer) {
+    if (event.headers?.Referer) {
       httpTags["http.referer"] = event.headers.Referer;
     }
     return httpTags;

src/trace/trigger.ts

@@ -11,13 +11,16 @@ import {
   SNSEvent,
   SQSEvent,
 } from "aws-lambda";
+import { apiGatewayEventV2 } from "../trace/constants";
 
 export function isAPIGatewayEvent(event: any): event is APIGatewayEvent {
-  return event.requestContext !== undefined && event.requestContext.stage !== undefined;
+  return event.requestContext?.stage !== undefined && event.httpMethod !== undefined && event.resource !== undefined;
 }
 
 export function isAPIGatewayEventV2(event: any): event is APIGatewayProxyEventV2 {
-  return event.requestContext !== undefined && event.version !== undefined;
+  return (
+    event.requestContext !== undefined && event.version === apiGatewayEventV2 && event.rawQueryString !== undefined
+  );
 }
 
 export function isALBEvent(event: any): event is ALBEvent {