com.google.endpoints.examples.bookstore.BookstoreServer.java Source code

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Here is the source code for com.google.endpoints.examples.bookstore.BookstoreServer.java

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// Copyright 2016 Google Inc.
//
// 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.
//
////////////////////////////////////////////////////////////////////////////////

package com.google.endpoints.examples.bookstore;

import io.grpc.Server;
import io.grpc.ServerBuilder;
import io.grpc.StatusException;

import java.io.IOException;
import java.util.concurrent.TimeUnit;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;

/**
 * Builds and starts a GRPC-based Bookstore server.
 */
public final class BookstoreServer {

    private static final int DEFAULT_PORT = 8000;

    public static void main(String[] args) throws Exception {
        Options options = createOptions();
        CommandLineParser parser = new DefaultParser();
        CommandLine line;
        try {
            line = parser.parse(options, args);
        } catch (ParseException e) {
            System.err.println("Invalid command line: " + e.getMessage());
            printUsage(options);
            return;
        }

        int port = DEFAULT_PORT;

        if (line.hasOption("port")) {
            String portOption = line.getOptionValue("port");
            try {
                port = Integer.parseInt(portOption);
            } catch (java.lang.NumberFormatException e) {
                System.err.println("Invalid port number: " + portOption);
                printUsage(options);
                return;
            }
        }

        final BookstoreData data = initializeBookstoreData();
        final BookstoreServer server = new BookstoreServer();
        Runtime.getRuntime().addShutdownHook(new Thread() {
            @Override
            public void run() {
                try {
                    System.out.println("Shutting down");
                    server.stop();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
        server.start(port, data);
        System.out.format("Bookstore service listening on %d\n", port);
        server.blockUntilShutdown();
    }

    private Server server;

    private void start(int port, BookstoreData data) throws IOException {
        server = ServerBuilder.forPort(port).addService(new BookstoreService(data)).build().start();
    }

    private void stop() throws Exception {
        server.shutdownNow();
        if (!server.awaitTermination(5, TimeUnit.SECONDS)) {
            System.err.println("Timed out waiting for server shutdown");
        }
    }

    private void blockUntilShutdown() throws InterruptedException {
        if (server != null) {
            server.awaitTermination();
        }
    }

    private static BookstoreData initializeBookstoreData() throws StatusException {
        BookstoreData data = new BookstoreData();
        ShelfEntity shelf = data.createShelf(Shelf.newBuilder().setTheme("Fiction").build());
        data.createBook(shelf.getShelfId(),
                Book.newBuilder().setAuthor("Neal Stephenson").setTitle("REAMDE").build());
        shelf = data.createShelf(Shelf.newBuilder().setTheme("Fantasy").build());
        data.createBook(shelf.getShelfId(),
                Book.newBuilder().setAuthor("George R. R. Martin").setTitle("A Game of Thrones").build());
        return data;
    }

    private static Options createOptions() {
        Options options = new Options();

        // port
        options.addOption(Option.builder().longOpt("port").desc("The port on which the server listens.").hasArg()
                .argName("port").type(Integer.class).build());

        return options;
    }

    private static void printUsage(Options options) {
        HelpFormatter formatter = new HelpFormatter();
        formatter.printHelp("client", "A simple Bookstore gRPC server for use with Endpoints.", options, "", true);
    }
}