/* * * Copyright 2015, Google Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution. * * Neither the name of Google Inc. nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ 'use strict'; var grpc = require('../..'); var grpcMath = require('./math_grpc_pb'); var math = require('./math_pb'); /** * Server function for division. Provides the /Math/DivMany and /Math/Div * functions (Div is just DivMany with only one stream element). For each * DivArgs parameter, responds with a DivReply with the results of the division * @param {Object} call The object containing request and cancellation info * @param {function(Error, *)} cb Response callback */ function mathDiv(call, cb) { var req = call.request; var divisor = req.getDivisor(); var dividend = req.getDividend(); // Unary + is explicit coersion to integer if (req.getDivisor() === 0) { cb(new Error('cannot divide by zero')); } else { var response = new math.DivReply(); response.setQuotient(Math.floor(dividend / divisor)); response.setRemainder(dividend % divisor); cb(null, response); } } /** * Server function for Fibonacci numbers. Provides the /Math/Fib function. Reads * a single parameter that indicates the number of responses, and then responds * with a stream of that many Fibonacci numbers. * @param {stream} stream The stream for sending responses. */ function mathFib(stream) { // Here, call is a standard writable Node object Stream var previous = 0, current = 1; for (var i = 0; i < stream.request.getLimit(); i++) { var response = new math.Num(); response.setNum(current); stream.write(response); var temp = current; current += previous; previous = temp; } stream.end(); } /** * Server function for summation. Provides the /Math/Sum function. Reads a * stream of number parameters, then responds with their sum. * @param {stream} call The stream of arguments. * @param {function(Error, *)} cb Response callback */ function mathSum(call, cb) { // Here, call is a standard readable Node object Stream var sum = 0; call.on('data', function(data) { sum += data.getNum(); }); call.on('end', function() { var response = new math.Num(); response.setNum(sum); cb(null, response); }); } function mathDivMany(stream) { stream.on('data', function(div_args) { var divisor = div_args.getDivisor(); var dividend = div_args.getDividend(); if (divisor === 0) { stream.emit('error', new Error('cannot divide by zero')); } else { var response = new math.DivReply(); response.setQuotient(Math.floor(dividend / divisor)); response.setRemainder(dividend % divisor); stream.write(response); } }); stream.on('end', function() { stream.end(); }); } function getMathServer() { var server = new grpc.Server(); server.addService(grpcMath.MathService, { div: mathDiv, fib: mathFib, sum: mathSum, divMany: mathDivMany }); return server; } if (require.main === module) { var server = getMathServer(); server.bind('0.0.0.0:50051', grpc.ServerCredentials.createInsecure()); server.start(); } /** * See docs for server */ module.exports = getMathServer;