/* * * Copyright 2024 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. * */ const grpc = require('@grpc/grpc-js'); const protoLoader = require('@grpc/proto-loader'); const parseArgs = require('minimist'); const PROTO_PATH = __dirname + '/../protos/echo.proto'; const packageDefinition = protoLoader.loadSync( PROTO_PATH, {keepCase: true, longs: String, enums: String, defaults: true, oneofs: true }); const echoProto = grpc.loadPackageDefinition(packageDefinition).grpc.examples.echo; const keepaliveOptions = { // Ping the server every 10 seconds to ensure the connection is still active 'grpc.keepalive_time_ms': 10_000, // Wait 1 second for the ping ack before assuming the connection is dead 'grpc.keepalive_timeout_ms': 1_000, // send pings even without active streams 'grpc.keepalive_permit_without_calls': 1 } function main() { let argv = parseArgs(process.argv.slice(2), { string: 'target', default: {target: 'localhost:50052'} }); const client = new echoProto.Echo(argv.target, grpc.credentials.createInsecure(), keepaliveOptions); client.unaryEcho({message: 'keepalive demo'}, (error, value) => { if (error) { console.log(`Unexpected error from UnaryEcho: ${error}`); return; } console.log(`RPC response: ${JSON.stringify(value)}`); }); // Keep process alive forever; run with GRPC_TRACE=transport,keepalive GRPC_VERBOSITY=DEBUG to observe ping frames and GOAWAYs due to idleness. setInterval(() => {}, 1000); } main();