From fdcff09f6b48fde2348efaac432fe6cd242faa51 Mon Sep 17 00:00:00 2001
From: Matt Loring <mattloring@google.com>
Date: Thu, 8 Jun 2017 11:00:40 -0700
Subject: [PATCH] Use service name as debuggee id on gke

---
 src/agent/debuglet.js | 21 ++++++++++++++++++---
 test/test-debuglet.js | 22 ++++++++++++++++++++++
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/src/agent/debuglet.js b/src/agent/debuglet.js
index 2cf7cda3..9f55cb67 100644
--- a/src/agent/debuglet.js
+++ b/src/agent/debuglet.js
@@ -146,6 +146,8 @@ Debuglet.normalizeConfig_ = function(config) {
   var envConfig = {
     logLevel: process.env.GCLOUD_DEBUG_LOGLEVEL,
     serviceContext: {
+      // If running on GKE, we will set service context later once
+      // the cluster name can be retrieved from the metadata service.
       service: process.env.GAE_SERVICE || process.env.GAE_MODULE_NAME,
       version: process.env.GAE_VERSION || process.env.GAE_MODULE_VERSION,
       // Debug UI expects GAE_MINOR_VERSION to be available for AppEngine, but
@@ -206,7 +208,7 @@ Debuglet.prototype.start = function() {
 
         that.logger_.info('Unique ID for this Application: ' + id);
 
-        that.getProjectId_(function(err, project, onGCP) {
+        that.getMetadataValues_(function(err, values) {
           if (err) {
             that.logger_.error('Unable to discover projectId. Please provide ' +
                                'the projectId to be able to use the Debuglet',
@@ -214,6 +216,15 @@ Debuglet.prototype.start = function() {
             that.emit('initError', err);
             return;
           }
+          var project = values.project;
+          var clusterName = values.clusterName;
+          var onGCP = values.onGCP;
+
+          if (clusterName) {
+            // If we succeeded to get a cluster name, we must be running on gke.
+            that.config_.serviceContext.service = clusterName;
+            that.config_.serviceContext.version = 'unversioned';
+          }
 
           that.getSourceContext_(function(err, sourceContext) {
             if (err) {
@@ -319,7 +330,7 @@ Debuglet.createDebuggee =
 /**
  * @private
  */
-Debuglet.prototype.getProjectId_ = function(callback) {
+Debuglet.prototype.getMetadataValues_ = function(callback) {
   var that = this;
 
   // We need to figure out whether we are running on GCP. We can use our ability
@@ -339,7 +350,11 @@ Debuglet.prototype.getProjectId_ = function(callback) {
         if (!project) {
           return callback(err);
         }
-        return callback(null, project, onGCP);
+        metadata.instance(
+          'attributes/cluster-name', function(err, response, metadataCluster) {
+            return callback(null,
+              { project: project, clusterName: metadataCluster, onGCP: onGCP});
+        });
       });
 };
 
diff --git a/test/test-debuglet.js b/test/test-debuglet.js
index c5919f98..144fde76 100644
--- a/test/test-debuglet.js
+++ b/test/test-debuglet.js
@@ -295,6 +295,28 @@ describe('Debuglet', function() {
            assert.ok(_.isString(debuglet.config_.serviceContext.minorVersion_));
          });
 
+      it('should use GKE cluster name if available', function(done) {
+        var scope = nock('http://metadata.google.internal')
+          .get('/computeMetadata/v1/instance/attributes/cluster-name')
+            .once()
+            .reply(200, 'my-cool-cluster');
+        var debug = require('../src/debug.js')(
+          {projectId: 'fake-project', credentials: fakeCredentials});
+        var debuglet = new Debuglet(debug, defaultConfig);
+        debuglet.once('started', function(id) {
+          debuglet.stop();
+          assert.ok(debuglet.config_);
+          assert.ok(debuglet.config_.serviceContext);
+          assert.strictEqual(debuglet.config_.serviceContext.service,
+                           'my-cool-cluster');
+          assert.strictEqual(debuglet.config_.serviceContext.version,
+                           'unversioned');
+          scope.done();
+          done();
+        });
+        debuglet.start();
+      });
+
       it('should not have minorVersion unless enviroment provides it',
          function() {
            var debug = require('../src/debug.js')();