main.go

/*
Copyright 2016 Mike Cheng

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 main

import (
	"encoding/json"
	"flag"
	"log"
	"net/http"
	"os"
	"sync"
)

var (
	configFile  = flag.String("config", "", "Configuration file")
	redirectMap = make(map[string]string)
)

type Config struct {
	TLSConfigs   []TLSConfig `json:"tls"`
	Redirections []Redirect  `json:"redirections"`
}

type TLSConfig struct {
	CertFile string `json:"cert"`
	KeyFile  string `json:"key"`
}

type Redirect struct {
	URL         string `json:"url"`
	RedirectURL string `json:"redirect"`
}

func loadConfig() Config {
	if *configFile == "" {
		log.Fatal("Must specify configuration file")
	}

	var config Config

	f, err := os.Open(*configFile)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	d := json.NewDecoder(f)
	err = d.Decode(&config)
	if err != nil {
		log.Fatal(err)
	}

	return config
}

func main() {
	flag.Parse()

	config := loadConfig()

	// Load all of the redirection configs
	for _, redirect := range config.Redirections {
		redirectMap[redirect.URL] = redirect.RedirectURL
	}

	http.HandleFunc("/", redirectHandler)

	var wg sync.WaitGroup
	wg.Add(2)

	go listenAndServe(&wg)
	go listenAndServeTLS(config, &wg)

	wg.Wait()
}