first-commit

modules/web/middleware/flash.go

@@ -0,0 +1,92 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package middleware
+
+import (
+	"fmt"
+	"html/template"
+	"net/http"
+	"net/url"
+
+	"code.gitea.io/gitea/modules/reqctx"
+)
+
+// Flash represents a one time data transfer between two requests.
+type Flash struct {
+	DataStore reqctx.RequestDataStore
+	url.Values
+	ErrorMsg, WarningMsg, InfoMsg, SuccessMsg string
+}
+
+func (f *Flash) set(name, msg string, current ...bool) {
+	if f.Values == nil {
+		f.Values = make(map[string][]string)
+	}
+	showInCurrentPage := len(current) > 0 && current[0]
+	if showInCurrentPage {
+		// assign it to the context data, then the template can use ".Flash.XxxMsg" to render the message
+		f.DataStore.GetData()["Flash"] = f
+	} else {
+		// the message map will be saved into the cookie and be shown in next response (a new page response which decodes the cookie)
+		f.Set(name, msg)
+	}
+}
+
+func flashMsgStringOrHTML(msg any) string {
+	switch v := msg.(type) {
+	case string:
+		return v
+	case template.HTML:
+		return string(v)
+	}
+	panic(fmt.Sprintf("unknown type: %T", msg))
+}
+
+// Error sets error message
+func (f *Flash) Error(msg any, current ...bool) {
+	f.ErrorMsg = flashMsgStringOrHTML(msg)
+	f.set("error", f.ErrorMsg, current...)
+}
+
+// Warning sets warning message
+func (f *Flash) Warning(msg any, current ...bool) {
+	f.WarningMsg = flashMsgStringOrHTML(msg)
+	f.set("warning", f.WarningMsg, current...)
+}
+
+// Info sets info message
+func (f *Flash) Info(msg any, current ...bool) {
+	f.InfoMsg = flashMsgStringOrHTML(msg)
+	f.set("info", f.InfoMsg, current...)
+}
+
+// Success sets success message
+func (f *Flash) Success(msg any, current ...bool) {
+	f.SuccessMsg = flashMsgStringOrHTML(msg)
+	f.set("success", f.SuccessMsg, current...)
+}
+
+func ParseCookieFlashMessage(val string) *Flash {
+	if vals, _ := url.ParseQuery(val); len(vals) > 0 {
+		return &Flash{
+			Values:     vals,
+			ErrorMsg:   vals.Get("error"),
+			SuccessMsg: vals.Get("success"),
+			InfoMsg:    vals.Get("info"),
+			WarningMsg: vals.Get("warning"),
+		}
+	}
+	return nil
+}
+
+func GetSiteCookieFlashMessage(dataStore reqctx.RequestDataStore, req *http.Request, cookieName string) (string, *Flash) {
+	// Get the last flash message from cookie
+	lastFlashCookie := GetSiteCookie(req, cookieName)
+	lastFlashMsg := ParseCookieFlashMessage(lastFlashCookie)
+	if lastFlashMsg != nil {
+		lastFlashMsg.DataStore = dataStore
+		return lastFlashCookie, lastFlashMsg
+	}
+	return lastFlashCookie, nil
+}