main.go

/*
A simple daemon that exposes a queue as a network service on the port of your
choice. `queued` is made available under a BSD license.
*/

package main

/* queued
 * Author: Tim Henderson
 * Email: tadh@case.edu
 * Copyright 2013 All Right 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 the queued 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 HOLDER 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.
 */

import (
	"fmt"
	"os"
	"strconv"
)

import (
	"github.com/timtadh/getopt"
)

import (
	"github.com/timtadh/queued/net"
	"github.com/timtadh/queued/queue"
)

var ErrorCodes map[string]int = map[string]int{
	"usage":   1,
	"version": 2,
	"opts":    3,
	"badint":  5,
}

var UsageMessage string = "queued <port>"
var ExtendedMessage string = `
starts a queued daemon, a simple queue exposed on the network.

Options
    -h, --help                          print this message
    --allow-dups                        allow duplicate items in the queue.
                                        This setting effects every queue

Specs
    <port>  A bindable port number.
`

func Usage(code int) {
	fmt.Fprintln(os.Stderr, UsageMessage)
	if code == 0 {
		fmt.Fprintln(os.Stderr, ExtendedMessage)
		code = ErrorCodes["usage"]
	} else {
		fmt.Fprintln(os.Stderr, "Try -h or --help for help")
	}
	os.Exit(code)
}

func parse_int(str string) int {
	i, err := strconv.Atoi(str)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error parsing '%v' expected an int\n", str)
		Usage(ErrorCodes["badint"])
	}
	return i
}

func main() {
	short := "h"
	long := []string{
		"help",
		"allow-dups",
	}
	args, optargs, err := getopt.GetOpt(os.Args[1:], short, long)
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		Usage(ErrorCodes["opts"])
	}

	port := -1
	dups := false
	for _, oa := range optargs {
		switch oa.Opt() {
		case "-h", "--help":
			Usage(0)
		case "--allow-dups":
			dups = true
		}
	}

	if len(args) != 1 {
		fmt.Fprintln(os.Stderr, "You must specify a port")
		Usage(ErrorCodes["opts"])
	}
	port = parse_int(args[0])

	fmt.Println("starting")
	server := net.NewServer(func() net.Queue { return queue.NewQueue(dups) })
	server.Start(port)
}