grpc-js-xds: interop server: Add support for sending custom metrics

Author: murgatroid99

packages/grpc-js-xds/interop/xds-interop-server.ts

@@ -232,12 +232,36 @@ function getIPv6Addresses(): string[] {
   return ipv6Addresses;
 }
 
+interface ConfiguredMetrics {
+  qps?: number;
+  applicationUtilization?: number;
+  eps?: number;
+}
+
+function createInBandMetricsInterceptor(metrics: ConfiguredMetrics) {
+  return function inBandMetricsInterceptor(methodDescriptor: grpc.ServerMethodDefinition<any, any>, call: grpc.ServerInterceptingCallInterface): grpc.ServerInterceptingCall {
+    const metricsRecorder = call.getMetricsRecorder()
+    if (metrics.qps) {
+      metricsRecorder.recordQpsMetric(metrics.qps);
+    }
+    if (metrics.applicationUtilization) {
+      metricsRecorder.recordApplicationUtilizationMetric(metrics.applicationUtilization);
+    }
+    if (metrics.eps) {
+      metricsRecorder.recordEpsMetric(metrics.eps);
+    }
+    return new grpc.ServerInterceptingCall(call);
+  }
+}
+
 async function main() {
   const argv = yargs
-    .string(['port', 'maintenance_port', 'address_type', 'secure_mode'])
+    .string(['port', 'maintenance_port', 'address_type', 'secure_mode', 'metrics_mode'])
+    .number(['qps', 'application_utilization', 'eps'])
     .demandOption(['port'])
     .default('address_type', 'IPV4_IPV6')
     .default('secure_mode', 'false')
+    .default('metrics_mode', 'NONE')
     .parse()
     console.log('Starting xDS interop server. Args: ', argv);
   const healthImpl = new HealthImplementation({'': 'NOT_SERVING'});
@@ -253,7 +277,28 @@ async function main() {
   }
   const reflection = new ReflectionService(packageDefinition, {
     services: ['grpc.testing.TestService']
-  })
+  });
+  let metricInterceptor: grpc.ServerInterceptor | null = null;
+  const metricsMode = argv.metrics_mode.toUpperCase();
+  let metricRecorder: grpc.ServerMetricRecorder | null = null;
+  if (metricsMode === 'IN_BAND') {
+    metricInterceptor = createInBandMetricsInterceptor({
+      qps: argv.qps,
+      applicationUtilization: argv.application_utilization,
+      eps: argv.eps
+    });
+  } else if (metricsMode === 'OUT_OF_BAND') {
+    metricRecorder = new grpc.ServerMetricRecorder();
+    if (argv.qps) {
+      metricRecorder.setQpsMetric(argv.qps);
+    }
+    if (argv.application_utilization) {
+      metricRecorder.setApplicationUtilizationMetric(argv.application_utilization);
+    }
+    if (argv.eps) {
+      metricRecorder.setEpsMetric(argv.eps);
+    }
+  }
   const addressType = argv.address_type.toUpperCase();
   const secureMode = argv.secure_mode.toLowerCase() == 'true';
   if (secureMode) {
@@ -266,19 +311,33 @@ async function main() {
     reflection.addToServer(maintenanceServer);
     grpc.addAdminServicesToServer(maintenanceServer);
 
-    const server = new grpc_xds.XdsServer({interceptors: [testInfoInterceptor]});
+    const interceptorList = [testInfoInterceptor];
+    if (metricInterceptor) {
+      interceptorList.push(metricInterceptor);
+    }
+    const server = new grpc_xds.XdsServer({interceptors: interceptorList});
     server.addService(loadedProto.grpc.testing.TestService.service, testServiceHandler);
+    if (metricRecorder) {
+      metricRecorder.addToServer(server);
+    }
     const xdsCreds = new grpc_xds.XdsServerCredentials(grpc.ServerCredentials.createInsecure());
     await Promise.all([
       serverBindPromise(maintenanceServer, `[::]:${argv.maintenance_port}`, grpc.ServerCredentials.createInsecure()),
       serverBindPromise(server, `0.0.0.0:${argv.port}`, xdsCreds)
     ]);
   } else {
+    const interceptorList = [unifiedInterceptor];
+    if (metricInterceptor) {
+      interceptorList.push(metricInterceptor);
+    }
     const server = new grpc.Server({interceptors: [unifiedInterceptor]});
     server.addService(loadedProto.grpc.testing.XdsUpdateHealthService.service, xdsUpdateHealthServiceImpl);
     healthImpl.addToServer(server);
     reflection.addToServer(server);
     grpc.addAdminServicesToServer(server);
+    if (metricRecorder) {
+      metricRecorder.addToServer(server);
+    }
     server.addService(loadedProto.grpc.testing.TestService.service, testServiceHandler);
     const creds = grpc.ServerCredentials.createInsecure();
     switch (addressType) {