Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/boards/api/statistics.go

@@ -0,0 +1,74 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package api
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/gorilla/mux"
+
+	mm_model "github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/server/boards/model"
+)
+
+func (a *API) registerStatisticsRoutes(r *mux.Router) {
+	// statistics
+	r.HandleFunc("/statistics", a.sessionRequired(a.handleStatistics)).Methods("GET")
+}
+
+func (a *API) handleStatistics(w http.ResponseWriter, r *http.Request) {
+	// swagger:operation GET /statistics handleStatistics
+	//
+	// Fetches the statistic  of the server.
+	//
+	// ---
+	// produces:
+	// - application/json
+	// security:
+	// - BearerAuth: []
+	// responses:
+	//   '200':
+	//     description: success
+	//     schema:
+	//         "$ref": "#/definitions/BoardStatistics"
+	//   default:
+	//     description: internal error
+	//     schema:
+	//       "$ref": "#/definitions/ErrorResponse"
+	if !a.MattermostAuth {
+		a.errorResponse(w, r, model.NewErrNotImplemented("not permitted in standalone mode"))
+		return
+	}
+
+	// user must have right to access analytics
+	userID := getUserID(r)
+	if !a.permissions.HasPermissionTo(userID, mm_model.PermissionGetAnalytics) {
+		a.errorResponse(w, r, model.NewErrPermission("access denied System Statistics"))
+		return
+	}
+
+	boardCount, err := a.app.GetBoardCount()
+	if err != nil {
+		a.errorResponse(w, r, err)
+		return
+	}
+	cardCount, err := a.app.GetUsedCardsCount()
+	if err != nil {
+		a.errorResponse(w, r, err)
+		return
+	}
+
+	stats := model.BoardsStatistics{
+		Boards: int(boardCount),
+		Cards:  cardCount,
+	}
+	data, err := json.Marshal(stats)
+	if err != nil {
+		a.errorResponse(w, r, err)
+		return
+	}
+
+	jsonBytesResponse(w, http.StatusOK, data)
+}