[API] Add notification endpoint (#9488)

* [API] Add notification endpoints

 * add func GetNotifications(opts FindNotificationOptions)
 * add func (n *Notification) APIFormat()
 * add func (nl NotificationList) APIFormat()
 * add func (n *Notification) APIURL()
 * add func (nl NotificationList) APIFormat()
 * add LoadAttributes functions (loadRepo, loadIssue, loadComment, loadUser)
 * add func (c *Comment) APIURL()
 * add func (issue *Issue) GetLastComment()
 * add endpoint GET /notifications
 * add endpoint PUT /notifications
 * add endpoint GET /repos/{owner}/{repo}/notifications
 * add endpoint PUT /repos/{owner}/{repo}/notifications
 * add endpoint GET /notifications/threads/{id}
 * add endpoint PATCH /notifications/threads/{id}

* Add TEST

* code format

* code format

routers/api/v1/notify/threads.go

@@ -0,0 +1,101 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package notify
+
+import (
+	"fmt"
+	"net/http"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/context"
+)
+
+// GetThread get notification by ID
+func GetThread(ctx *context.APIContext) {
+	// swagger:operation GET /notifications/threads/{id} notification notifyGetThread
+	// ---
+	// summary: Get notification thread by ID
+	// consumes:
+	// - application/json
+	// produces:
+	// - application/json
+	// parameters:
+	// - name: id
+	//   in: path
+	//   description: id of notification thread
+	//   type: string
+	//   required: true
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/NotificationThread"
+	//   "403":
+	//     "$ref": "#/responses/forbidden"
+	//   "404":
+	//     "$ref": "#/responses/notFound"
+
+	n := getThread(ctx)
+	if n == nil {
+		return
+	}
+	if err := n.LoadAttributes(); err != nil {
+		ctx.InternalServerError(err)
+		return
+	}
+
+	ctx.JSON(http.StatusOK, n.APIFormat())
+}
+
+// ReadThread mark notification as read by ID
+func ReadThread(ctx *context.APIContext) {
+	// swagger:operation PATCH /notifications/threads/{id} notification notifyReadThread
+	// ---
+	// summary: Mark notification thread as read by ID
+	// consumes:
+	// - application/json
+	// produces:
+	// - application/json
+	// parameters:
+	// - name: id
+	//   in: path
+	//   description: id of notification thread
+	//   type: string
+	//   required: true
+	// responses:
+	//   "205":
+	//     "$ref": "#/responses/empty"
+	//   "403":
+	//     "$ref": "#/responses/forbidden"
+	//   "404":
+	//     "$ref": "#/responses/notFound"
+
+	n := getThread(ctx)
+	if n == nil {
+		return
+	}
+
+	err := models.SetNotificationStatus(n.ID, ctx.User, models.NotificationStatusRead)
+	if err != nil {
+		ctx.InternalServerError(err)
+		return
+	}
+	ctx.Status(http.StatusResetContent)
+}
+
+func getThread(ctx *context.APIContext) *models.Notification {
+	n, err := models.GetNotificationByID(ctx.ParamsInt64(":id"))
+	if err != nil {
+		if models.IsErrNotExist(err) {
+			ctx.Error(http.StatusNotFound, "GetNotificationByID", err)
+		} else {
+			ctx.InternalServerError(err)
+		}
+		return nil
+	}
+	if n.UserID != ctx.User.ID && !ctx.User.IsAdmin {
+		ctx.Error(http.StatusForbidden, "GetNotificationByID", fmt.Errorf("only user itself and admin are allowed to read/change this thread %d", n.ID))
+		return nil
+	}
+	return n
+}