Add webhook

main.go

@@ -2,12 +2,14 @@ package main
 
 import (
 	"bytes"
+	"encoding/json"
 	"flag"
 	"html/template"
 	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
+	"os/exec"
 	"path"
 	"strconv"
 	"strings"
@@ -18,6 +20,8 @@ import (
 func main() {
 	loadConfig()
 
+	_ = os.Setenv(`GIT_TERMINAL_PROMPT`, `0`)
+
 	if err := updateTemplate(); err != nil {
 		log.Fatal(`Failed to load template. (` + err.Error() + `)`)
 	}
@@ -30,6 +34,7 @@ var config struct {
 	Template string
 	Pages    string
 	Static   string
+	Webhook  string
 }
 
 func loadConfig() {
@@ -37,21 +42,49 @@ func loadConfig() {
 	flag.StringVar(&config.Template, `template`, `template.html`, `The template used by mdsite`)
 	flag.StringVar(&config.Pages, `pages`, `pages`, `The OS path used when searching a page`)
 	flag.StringVar(&config.Static, `static`, `static`, `The OS path used for static resource`)
+	flag.StringVar(&config.Webhook, `webhook`, ``, `The secret for webhooks to update the content`)
 	flag.Parse()
 }
 
 var t *template.Template
 
 func updateTemplate() error {
-	var err error
+	tmpl, err := template.ParseFiles(config.Template)
-	t, err = template.ParseFiles(config.Template)
 	if err != nil {
 		return err
 	}
+
+	t = tmpl
 	return nil
 }
 
 func serveRequest(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodPost && config.Webhook != `` && r.URL.Path == `/hook` {
+		var input struct {
+			Secret string `json:"secret"`
+		}
+		err := json.NewDecoder(r.Body).Decode(&input)
+		_ = r.Body.Close()
+		if err != nil || input.Secret != config.Webhook {
+			w.WriteHeader(403)
+			return
+		}
+
+		err = exec.Command(`git`, `fetch`).Run()
+		if err == nil {
+			err = exec.Command(`git`, `reset`, `--hard`, `origin/master`).Run()
+		}
+		if err == nil {
+			err = updateTemplate()
+		}
+
+		if err != nil {
+			w.WriteHeader(500)
+			w.Write([]byte(`Update failed`))
+		}
+		return
+	}
+
 	if strings.HasPrefix(r.URL.Path, `/static/`) {
 		path := path.Join(config.Static, path.Clean(strings.TrimPrefix(r.URL.Path, `/static/`)))
 		http.ServeFile(w, r, path)