Switch to standard health RPC

pb/demo.proto

@@ -120,7 +120,6 @@ message Address {
 service CurrencyService {
     rpc GetSupportedCurrencies(Empty) returns (GetSupportedCurrenciesResponse) {}
     rpc Convert(CurrencyConversionRequest) returns (Money) {}
-    rpc Check(Empty) returns (Empty) {}
 }
 
 // Represents an amount of money with its currency type.
@@ -157,7 +156,6 @@ message CurrencyConversionRequest {
 
 service PaymentService {
     rpc Charge(ChargeRequest) returns (ChargeResponse) {}
-    rpc Check(Empty) returns (Empty) {}
 }
 
 message CreditCardInfo {

pb/grpc/health/v1/health.proto

@@ -0,0 +1,43 @@
+// Copyright 2015 The gRPC Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// The canonical version of this proto can be found at
+// https://github.com/grpc/grpc-proto/blob/master/grpc/health/v1/health.proto
+
+syntax = "proto3";
+
+package grpc.health.v1;
+
+option csharp_namespace = "Grpc.Health.V1";
+option go_package = "google.golang.org/grpc/health/grpc_health_v1";
+option java_multiple_files = true;
+option java_outer_classname = "HealthProto";
+option java_package = "io.grpc.health.v1";
+
+message HealthCheckRequest {
+  string service = 1;
+}
+
+message HealthCheckResponse {
+  enum ServingStatus {
+    UNKNOWN = 0;
+    SERVING = 1;
+    NOT_SERVING = 2;
+  }
+  ServingStatus status = 1;
+}
+
+service Health {
+  rpc Check(HealthCheckRequest) returns (HealthCheckResponse);
+}

src/currencyservice/genproto.sh

@@ -17,4 +17,4 @@
 #!/bin/bash -e
 # protos are loaded dynamically for node, simply copies over the proto.
 mkdir -p proto && \
-cp ../../pb/demo.proto proto
+cp -r ../../pb/ proto/

src/currencyservice/package.json

@@ -8,6 +8,7 @@
     "@google-cloud/debug-agent": "^2.6.0",
     "@google-cloud/profiler": "^0.1.14",
     "@google-cloud/trace-agent": "^2.11.0",
+    "@grpc/proto-loader": "^0.3.0",
     "async": "^1.5.2",
     "google-protobuf": "^3.0.0",
     "grpc": "^1.0.0",

src/currencyservice/server.js

@@ -32,11 +32,33 @@ const path = require('path');
 const grpc = require('grpc');
 const request = require('request');
 const xml2js = require('xml2js');
+const protoLoader = require('@grpc/proto-loader');
+
+const MAIN_PROTO_PATH = path.join(__dirname, './proto/demo.proto');
+const HEALTH_PROTO_PATH = path.join(__dirname, './proto/grpc/health/v1/health.proto');
 
-const PROTO_PATH = path.join(__dirname, './proto/demo.proto');
 const PORT = 7000;
 const DATA_URL = 'http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml';
-const shopProto = grpc.load(PROTO_PATH).hipstershop;
+
+const shopProto = _loadProto(MAIN_PROTO_PATH).hipstershop;
+const healthProto = _loadProto(HEALTH_PROTO_PATH).grpc.health.v1;
+
+/**
+ * Helper function that loads a protobuf file.
+ */
+function _loadProto (path) {
+  const packageDefinition = protoLoader.loadSync(
+    path,
+    {
+      keepCase: true,
+      longs: String,
+      enums: String,
+      defaults: true,
+      oneofs: true
+    }
+  );
+  return grpc.loadPackageDefinition(packageDefinition);
+}
 
 /**
  * Helper function that gets currency data from an XML webpage
@@ -134,7 +156,7 @@ function convert (call, callback) {
  * Endpoint for health checks
  */
 function check (call, callback) {
-  callback(null);
+  callback(null, { status: 'SERVING' });
 }
 
 /**
@@ -144,7 +166,8 @@ function check (call, callback) {
 function main () {
   console.log(`Starting gRPC server on port ${PORT}...`);
   const server = new grpc.Server();
-  server.addService(shopProto.CurrencyService.service, {getSupportedCurrencies, convert, check});
+  server.addService(shopProto.CurrencyService.service, {getSupportedCurrencies, convert});
+  server.addService(healthProto.Health.service, {check});
   server.bind(`0.0.0.0:${PORT}`, grpc.ServerCredentials.createInsecure());
   server.start();
 }

src/paymentservice/genproto.sh

@@ -15,8 +15,6 @@
 # limitations under the License.
 
 #!/bin/bash -e
-
 # protos are loaded dynamically for node, simply copies over the proto.
-
 mkdir -p proto && \
-cp ../../pb/demo.proto proto
+cp -r ../../pb/ proto/

src/paymentservice/index.js

@@ -33,7 +33,7 @@ require('@google-cloud/debug-agent').start({
 const HipsterShopServer = require('./server');
 
 const PORT = process.env['PORT'];
-const PROTO_PATH = __dirname + '/proto/demo.proto';
+const PROTO_PATH = __dirname + '/proto/';
 
 const server = new HipsterShopServer(PROTO_PATH, PORT);
 

src/paymentservice/server.js

@@ -12,17 +12,23 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+const path = require('path');
 const grpc = require('grpc');
 const protoLoader = require('@grpc/proto-loader');
 
 const charge = require('./charge');
 
 class HipsterShopServer {
-  constructor(protoFile, port = HipsterShopServer.DEFAULT_PORT) {
+  constructor(protoRoot, port = HipsterShopServer.DEFAULT_PORT) {
     this.port = port;
 
+    this.packages = {
+      hipsterShop: this.loadProtoFile(path.join(protoRoot, 'demo.proto')),
+      health: this.loadProtoFile(path.join(protoRoot, 'grpc/health/v1/health.proto'))
+    };
+
     this.server = new grpc.Server();
-    this.loadProto(protoFile);
+    this.loadAllProtos(protoRoot);
   }
 
   /**
@@ -42,7 +48,7 @@ class HipsterShopServer {
   }
 
   static CheckHandler(call, callback) {
-    callback(null);
+    callback(null, { status: 'SERVING' });
   }
 
   listen() {
@@ -62,17 +68,23 @@ class HipsterShopServer {
         oneofs: true,
       }
     );
-    const protoDescriptor = grpc.loadPackageDefinition(packageDefinition);
-    const hipsterShopPackage = protoDescriptor.hipstershop;
-
-    this.addProtoService(hipsterShopPackage.PaymentService.service);
+    return grpc.loadPackageDefinition(packageDefinition);
   }
 
-  addProtoService(service) {
+  loadAllProtos(protoRoot) {
+    const hipsterShopPackage = this.packages.hipsterShop.hipstershop;
+    const healthPackage = this.packages.health.grpc.health.v1;
+
     this.server.addService(
-      service,
+      hipsterShopPackage.PaymentService.service,
       {
         charge: HipsterShopServer.ChargeServiceHandler.bind(this),
+      }
+    );
+
+    this.server.addService(
+      healthPackage.Health.service,
+      {
         check: HipsterShopServer.CheckHandler.bind(this)
       }
     );