Propagate trace context header (#118)

Author: crdgonzalezca

examples/user_interaction/client/src/App.js

@@ -58,7 +58,6 @@ class App extends React.Component {
         const data = JSON.parse(xhr.responseText)
         const result = this.callCalculatePi();
         this.setState({ pi: result, prime_numbers: data });
-        this.props.history.push('/second_page');
       }
     };
 

examples/user_interaction/client/src/index.js

@@ -45,6 +45,8 @@ const routing = (
 ReactDOM.render(routing, document.getElementById('root'));
 
 window.ocAgent = 'http://localhost:55678';
+// For the purpose of this example, send trace header to all hosts.
+window.ocTraceHeaderHostRegex = /.*/;
 window.ocSampleRate = 1.0; // Sample at 100% for test only. Default is 1/10000.
 
 // Send the root span and child spans for the initial page load to the

examples/user_interaction/server/package-lock.json

@@ -21,9 +21,9 @@
     "node": ">=8"
   },
   "dependencies": {
-    "@opencensus/exporter-zipkin": "^0.0.12",
-    "@opencensus/nodejs": "^0.0.12",
-    "@opencensus/propagation-tracecontext": "^0.0.12",
+    "@opencensus/exporter-zipkin": "^0.0.14",
+    "@opencensus/nodejs": "^0.0.14",
+    "@opencensus/propagation-tracecontext": "^0.0.14",
     "http": "*",
     "sleep": "^6.1.0"
   },

examples/user_interaction/server/package.json

@@ -63,25 +63,34 @@ function calculatePrimeNumbers() {
 
 /** A function which handles requests and send response. */
 function handleRequest(request, response) {
-  const span = tracer.startChildSpan({ name: 'octutorials.handleRequest' });
+  const span = tracer.startChildSpan({ name: 'ocweb.handleRequest' });
 
   try {
     let body = [];
     request.on('error', err => console.log(err));
     request.on('data', chunk => body.push(chunk));
 
-    // Necessary headers because the Node.js and React dev servers run in different ports.
-    response.setHeader('Access-Control-Allow-Origin', '*');
-    response.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, PATCH, DELETE');
-    response.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type');
-    response.setHeader('Access-Control-Allow-Credentials', true);
-
+    // Necessary header because the Node.js and React dev servers run in different ports.
+    response.setHeader('Access-Control-Allow-Origin', '*');    
+    
     let result = '';
     let code = 200;
+    // Accept all CORS pre-flight requests
+    if(request.method === 'OPTIONS'){
+      // Set headers to allow traceparent and subsequent get request.
+      response.setHeader('Access-Control-Allow-Headers', 'traceparent');
+      response.setHeader('Access-Control-Allow-Methods', 'GET');
+      request.on('end', () => {
+        span.end();
+        response.statusCode = code;
+        response.end();
+      });
+      return;
+    }
     if (url.parse(request.url).pathname === '/sleep') {
       console.log("Sleeping...")
       const time = Date.now();
-      sleep.sleep(5);
+      sleep.sleep(2);
       result = { time: Date.now() - time, value: "" };
       console.log("Finished.")
     } else if (url.parse(request.url).pathname === '/prime_numbers') {
@@ -109,7 +118,7 @@ function handleRequest(request, response) {
 function setupTracerAndExporters() {
   const zipkinOptions = {
     url: 'http://localhost:9411/api/v2/spans',
-    serviceName: 'opencensus_tutorial'
+    serviceName: 'opencensus_web_server'
   };
 
   // Creates Zipkin exporter

examples/user_interaction/server/server.js

@@ -68,7 +68,8 @@
   },
   "dependencies": {
     "@opencensus/web-core": "^0.0.3",
-    "@opencensus/web-exporter-ocagent": "^0.0.3"
+    "@opencensus/web-exporter-ocagent": "^0.0.3",
+    "@opencensus/web-propagation-tracecontext": "0.0.3"
   },
   "peerDependencies": {
     "zone.js": "~0.9.1"

packages/opencensus-web-instrumentation-zone/package-lock.json

@@ -24,6 +24,7 @@ const windowWithOcwGlobals = window as WindowWithOcwGlobals;
 const TRACE_ENDPOINT = '/v1/trace';
 
 import { InteractionTracker } from './interaction-tracker';
+import { doPatching } from './monkey-patching';
 
 function setupExporter() {
   if (!windowWithOcwGlobals.ocAgent) {
@@ -39,6 +40,7 @@ function setupExporter() {
 }
 
 export function startInteractionTracker() {
+  doPatching();
   setupExporter();
   InteractionTracker.startTracking();
 }