日志和错误处理

Author: nonfu

handlers/auth.go

@@ -1,7 +1,6 @@
 package handlers
 
 import (
-    "fmt"
     "github.com/xueyuanjun/chitchat/models"
     "net/http"
 )
@@ -24,15 +23,15 @@ func Signup(writer http.ResponseWriter, request *http.Request) {
 func SignupAccount(writer http.ResponseWriter, request *http.Request) {
     err := request.ParseForm()
     if err != nil {
-        fmt.Println("Cannot parse form")
+        danger(err, "Cannot parse form")
     }
     user := models.User{
         Name:     request.PostFormValue("name"),
         Email:    request.PostFormValue("email"),
         Password: request.PostFormValue("password"),
     }
     if err := user.Create(); err != nil {
-        fmt.Println("Cannot create user")
+        danger(err, "Cannot create user")
     }
     http.Redirect(writer, request, "/login", 302)
 }
@@ -43,12 +42,12 @@ func Authenticate(writer http.ResponseWriter, request *http.Request) {
     err := request.ParseForm()
     user, err := models.UserByEmail(request.PostFormValue("email"))
     if err != nil {
-        fmt.Println("Cannot find user")
+        danger(err, "Cannot find user")
     }
     if user.Password == models.Encrypt(request.PostFormValue("password")) {
         session, err := user.CreateSession()
         if err != nil {
-            fmt.Println("Cannot create session")
+            danger(err, "Cannot create session")
         }
         cookie := http.Cookie{
             Name:     "_cookie",
@@ -67,7 +66,7 @@ func Authenticate(writer http.ResponseWriter, request *http.Request) {
 func Logout(writer http.ResponseWriter, request *http.Request) {
     cookie, err := request.Cookie("_cookie")
     if err != http.ErrNoCookie {
-        fmt.Println("Failed to get cookie")
+        warning(err, "Failed to get cookie")
         session := models.Session{Uuid: cookie.Value}
         session.DeleteByUUID()
     }

handlers/helper.go

@@ -5,9 +5,22 @@ import (
     "fmt"
     "github.com/xueyuanjun/chitchat/models"
     "html/template"
+    "log"
     "net/http"
+    "os"
+    "strings"
 )
 
+var logger *log.Logger
+
+func init()  {
+    file, err := os.OpenFile("logs/chitchat.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+    if err != nil {
+        log.Fatalln("Failed to open log file", err)
+    }
+    logger = log.New(file, "INFO ", log.Ldate|log.Ltime|log.Lshortfile)
+}
+
 // Checks if the user is logged in and has a session, if not err is not nil
 func session(writer http.ResponseWriter, request *http.Request) (sess models.Session, err error) {
     cookie, err := request.Cookie("_cookie")
@@ -45,4 +58,26 @@ func generateHTML(writer http.ResponseWriter, data interface{}, filenames ...str
 // version
 func Version() string {
     return "0.1"
-}
+}
+
+// 记录日志信息
+func info(args ...interface{}) {
+    logger.SetPrefix("INFO ")
+    logger.Println(args...)
+}
+
+func danger(args ...interface{}) {
+    logger.SetPrefix("ERROR ")
+    logger.Println(args...)
+}
+
+func warning(args ...interface{}) {
+    logger.SetPrefix("WARNING ")
+    logger.Println(args...)
+}
+
+// 异常处理统一重定向到错误页面
+func error_message(writer http.ResponseWriter, request *http.Request, msg string) {
+    url := []string{"/err?msg=", msg}
+    http.Redirect(writer, request, strings.Join(url, ""), 302)
+}

handlers/index.go

@@ -16,3 +16,13 @@ func Index(writer http.ResponseWriter, request *http.Request) {
         }
     }
 }
+
+func Err(writer http.ResponseWriter, request *http.Request)  {
+    vals := request.URL.Query()
+    _, err := session(writer, request)
+    if err != nil {
+        generateHTML(writer, vals.Get("msg"), "layout", "navbar", "error")
+    } else {
+        generateHTML(writer, vals.Get("msg"), "layout", "auth.navbar", "error")
+    }
+}

handlers/post.go

@@ -15,20 +15,20 @@ func PostThread(writer http.ResponseWriter, request *http.Request) {
     } else {
         err = request.ParseForm()
         if err != nil {
-            fmt.Println("Cannot parse form")
+            danger(err, "Cannot parse form")
         }
         user, err := sess.User()
         if err != nil {
-            fmt.Println("Cannot get user from session")
+            danger(err, "Cannot get user from session")
         }
         body := request.PostFormValue("body")
         uuid := request.PostFormValue("uuid")
         thread, err := models.ThreadByUUID(uuid)
         if err != nil {
-            fmt.Println("Cannot read thread")
+            error_message(writer, request, "Cannot read thread")
         }
         if _, err := user.CreatePost(thread, body); err != nil {
-            fmt.Println("Cannot create post")
+            danger(err, "Cannot create post")
         }
         url := fmt.Sprint("/thread/read?id=", uuid)
         http.Redirect(writer, request, url, 302)

handlers/thread.go

@@ -1,7 +1,6 @@
 package handlers
 
 import (
-    "fmt"
     "github.com/xueyuanjun/chitchat/models"
     "net/http"
 )
@@ -26,15 +25,15 @@ func CreateThread(writer http.ResponseWriter, request *http.Request) {
     } else {
         err = request.ParseForm()
         if err != nil {
-            fmt.Println("Cannot parse form")
+            danger(err, "Cannot parse form")
         }
         user, err := sess.User()
         if err != nil {
-            fmt.Println("Cannot get user from session")
+            danger(err, "Cannot get user from session")
         }
         topic := request.PostFormValue("topic")
         if _, err := user.CreateThread(topic); err != nil {
-            fmt.Println("Cannot create thread")
+            danger(err, "Cannot create thread")
         }
         http.Redirect(writer, request, "/", 302)
     }
@@ -47,7 +46,7 @@ func ReadThread(writer http.ResponseWriter, request *http.Request) {
     uuid := vals.Get("id")
     thread, err := models.ThreadByUUID(uuid)
     if err != nil {
-        fmt.Println("Cannot read thread")
+        error_message(writer, request, "Cannot read thread")
     } else {
         _, err := session(writer, request)
         if err != nil {

logs/chitchat.log

@@ -0,0 +1 @@
+ERROR 2020/04/07 14:55:39 helper.go:71: sql: no rows in result set Cannot find user

main.go

@@ -7,7 +7,7 @@ import (
 )
 
 func main()  {
-    startWebServer("8080")
+    startWebServer("8000")
 }
 
 // 通过指定端口启动 Web 服务器

routes/routes.go

@@ -55,10 +55,10 @@ var webRoutes = WebRoutes{
         handlers.Logout,
     },
     {
-            "newThread",
-            "GET",
-            "/thread/new",
-            handlers.NewThread,
+        "newThread",
+        "GET",
+        "/thread/new",
+        handlers.NewThread,
     },
     {
         "createThread",
@@ -78,4 +78,10 @@ var webRoutes = WebRoutes{
         "/thread/post",
         handlers.PostThread,
     },
+    {
+        "error",
+        "GET",
+        "/err",
+        handlers.Err,
+    },
 }

views/error.html

@@ -0,0 +1,5 @@
+{{ define "content" }}
+
+<p class="lead">{{ . }}</p>
+
+{{ end }}