Add grpc-gcp support in gax

package.json

@@ -14,6 +14,7 @@
     "google-auth-library": "^3.0.0",
     "google-proto-files": "^0.18.0",
     "grpc": "^1.16.0",
+    "grpc-gcp": "^0.1.1",
     "is-stream-ended": "^0.1.4",
     "lodash.at": "^4.6.0",
     "lodash.has": "^4.5.2",

src/grpc.ts

@@ -35,6 +35,7 @@ import * as fs from 'fs';
 import {GoogleAuth, GoogleAuthOptions} from 'google-auth-library';
 import {getProtoPath} from 'google-proto-files';
 import * as grpcTypes from 'grpc';  // for types only
+import * as grpcGcp from 'grpc-gcp';
 import {OutgoingHttpHeaders} from 'http';
 import * as path from 'path';
 import * as protobuf from 'protobufjs';
@@ -286,13 +287,17 @@ export class GrpcClient {
       Object.keys(options).forEach(key => {
         if (key.indexOf('grpc.') === 0) {
           grpcOptions[key] = options[key];
-        } else if (key.indexOf('grpc_gcp.') === 0) {
-          // This prefix is used to pass additional arguments that aren't
-          // options for grpc. Strip the prefix before passing.
-          const prefixLength = 'grpc_gcp.'.length;
-          grpcOptions[key.substr(prefixLength)] = options[key];
         }
       });
+      const apiConfigDefinition = options['grpc_gcp.apiConfig'];
+      if (apiConfigDefinition) {
+        const apiConfig = grpcGcp.createGcpApiConfig(apiConfigDefinition);
+        grpcOptions['channelFactoryOverride'] =
+            grpcGcp.gcpChannelFactoryOverride;
+        grpcOptions['callInvocationTransformer'] =
+            grpcGcp.gcpCallInvocationTransformer;
+        grpcOptions['gcpApiConfig'] = apiConfig;
+      }
       return new CreateStub(serviceAddress, credentials, grpcOptions);
     });
   }

test/grpc.ts

@@ -128,6 +128,7 @@ describe('grpc', () => {
   });
 
   describe('createStub', () => {
+    const TEST_PATH = path.resolve(__dirname, '../../test');
     class DummyStub {
       constructor(public address, public creds, public options) {}
     }
@@ -177,7 +178,6 @@ describe('grpc', () => {
         port: 443,
         'grpc.max_send_message_length': 10 * 1024 * 1024,
         'grpc.initial_reconnect_backoff_ms': 10000,
-        'grpc_gcp.non_grpc_option': 1,
         other_dummy_options: 'test',
       };
       return grpcClient.createStub(DummyStub, opts).then(stub => {
@@ -186,8 +186,7 @@ describe('grpc', () => {
         expect(stub.creds).to.deep.eq(dummyChannelCreds);
         // tslint:disable-next-line no-any
         (expect(stub.options).has as any).key([
-          'grpc.max_send_message_length', 'grpc.initial_reconnect_backoff_ms',
-          'non_grpc_option'
+          'grpc.max_send_message_length', 'grpc.initial_reconnect_backoff_ms'
         ]);
         // tslint:disable-next-line no-any
         (expect(stub.options).to.not.have as any).key([
@@ -196,6 +195,33 @@ describe('grpc', () => {
       });
     });
 
+    it('supports grpc-gcp options', () => {
+      const apiConfigDefinition =
+          require(path.resolve(TEST_PATH, 'test_grpc_config.json'));
+      const opts = {
+        servicePath: 'foo.example.com',
+        port: 443,
+        'grpc_gcp.apiConfig': apiConfigDefinition,
+      };
+      return grpcClient.createStub(DummyStub, opts).then(stub => {
+        expect(stub).to.be.an.instanceOf(DummyStub);
+        expect(stub.address).to.eq('foo.example.com:443');
+        expect(stub.creds).to.deep.eq(dummyChannelCreds);
+        // tslint:disable-next-line no-any
+        (expect(stub.options).has as any).key([
+          'channelFactoryOverride', 'callInvocationTransformer', 'gcpApiConfig'
+        ]);
+        // tslint:disable-next-line no-any
+        (expect(stub.options).to.not.have as any).key([
+          'servicePath', 'port', 'grpc_gcp.apiConfig'
+        ]);
+        // tslint:disable-next-line no-any
+        (expect(stub.options['gcpApiConfig']).has as any).key([
+          'channelPool', 'method'
+        ]);
+      });
+    });
+
     it('uses the passed grpc channel', () => {
       const customCreds = {channelCreds: 'custom'};
       const opts = {

test/test_grpc_config.json

@@ -0,0 +1,15 @@
+{
+	"channelPool": {
+		"maxSize": 1,
+		"maxConcurrentStreamsLowWatermark": 1
+    },
+    "method": [
+        {
+            "name": ["method1"],
+            "affinity": {
+                "command": "BIND",
+                "affinityKey": "key1"
+            }
+        }
+    ]
+}