main.go

package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"net/http"
	"net/url"
	"os"
	"strconv"
	"sync"
)

const (
	cacheDB     = 2        // 存储数据的redis db
	cachePrefix = "gonews" // 缓存前缀
)

var dir string
var act string
var port int
var pullInterval int64 // 自动拉取间隔

var wg sync.WaitGroup

func init() {
	flag.StringVar(&dir, "d", "", "the path of news to parse")
	flag.StringVar(&act, "a", "cache", "the action to run service, values 'api' or 'cache'")
	flag.IntVar(&port, "p", 8017, "the port to listen for api service")
	flag.Int64Var(&pullInterval, "pull", 60, "the time interval (minutes) to pull data source, ")
}

func main() {
	flag.Parse()
	if act == "api" { // web服务
		http.HandleFunc("/", showApis)
		http.HandleFunc("/news", getNewsApi) // 获取新闻数据api
		err := http.ListenAndServe(":"+strconv.Itoa(port), nil)
		if err != nil {
			fmt.Fprintf(os.Stderr, "ListenAndServe error：%s", err)
			os.Exit(1)
		}
		fmt.Fprintf(os.Stdout, "%s", "Success to run api service")
	} else { // 缓存数据操作
		initDataPuller(dir, pullInterval)
		select {}
	}
}

// 并发缓存数据
func cacheNews(path string) {
	defer wg.Done()
	news := getNews(path)
	for _, item := range news {
		cache := map[string]interface{}{
			"id":    strconv.Itoa(int(item.ID)),
			"title": item.Title,
			"link":  item.Link.String(),
			"ctime": item.Ctime.Format("20060102"),
		}
		setNewsCache(cache) // 缓存数据
	}
}

// 首页展示api列表
func showApis(w http.ResponseWriter, req *http.Request) {
	w.Write([]byte(`{"apis":["/news"]}`))
}

// 获取新闻的api
func getNewsApi(w http.ResponseWriter, req *http.Request) {
	page := int64(1)
	per := int64(50)
	keyword := ""
	query, err := url.ParseQuery(req.URL.RawQuery)
	if err == nil {
		if len(query["page"]) > 0 && query["page"][0] != "" {
			iPage, _ := strconv.Atoi(query["page"][0])
			page = int64(iPage)
		}
		if len(query["per"]) > 0 && query["per"][0] != "" {
			iPer, _ := strconv.Atoi(query["per"][0])
			per = int64(iPer)
		}
		if len(query["keyword"]) > 0 && query["keyword"][0] != "" {
			keyword = query["keyword"][0]
		}
	}
	var news []map[string]string
	var count int64 = 0
	if keyword != "" {
		news, count = searchNews(keyword, page, per)
	} else {
		news, count = getAllNews(page, per)
	}
	data := map[string]interface{}{
		"total": count,
		"per":   per,
		"items": news,
	}
	jData, _ := json.Marshal(data)
	w.Write(jData)
}