[MM-55726] Create batch report worker, add batch report job for exporting users to CSV (#25832)

* Split out migration logic and create generic BatchWorker

* WIP

* WIP

* POC batch reporting

* Oops

* Job hookup

* Working export to file

* PR feedback

* Merge'd

* Fix error handling

* Add API to start report, translations, couple fixes

* Add DMs to send reports to users

* Merge'd

* Update types

* A bit of cleanup

* Some fixes

* Add missing API doc

* PR feedback

* Fix generated

* Fix bug with post creation

* PR feedback

* Add some tests

* PR feedback

* Fix lint

* Some test changes

* Fix tests

* Add comment to explain why we forcibly stop

* Rework of some tests

* Batch report test

* Restrict batch exports to Pro and Enterprise licenses

* Fix erroneous comment

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/api4/report.go

@@ -17,10 +17,13 @@ import (
 func (api *API) InitReports() {
 	api.BaseRoutes.Reports.Handle("/users", api.APISessionRequired(getUsersForReporting)).Methods("GET")
 	api.BaseRoutes.Reports.Handle("/users/count", api.APISessionRequired(getUserCountForReporting)).Methods("GET")
+	api.BaseRoutes.Reports.Handle("/users/export", api.APISessionRequired(startUsersBatchExport)).Methods("POST")
+
+	api.BaseRoutes.Reports.Handle("/export/{report_id:[A-Za-z0-9]+}", api.APISessionRequired(retrieveBatchReportFile)).Methods("GET")
 }
 
 func getUsersForReporting(c *Context, w http.ResponseWriter, r *http.Request) {
-	if !(c.IsSystemAdmin() && c.App.SessionHasPermissionTo(*c.AppContext.Session(), model.PermissionSysconsoleReadUserManagementUsers)) {
+	if !(c.IsSystemAdmin()) {
 		c.SetPermissionError(model.PermissionSysconsoleReadUserManagementUsers)
 		return
 	}
@@ -51,7 +54,7 @@ func getUsersForReporting(c *Context, w http.ResponseWriter, r *http.Request) {
 }
 
 func getUserCountForReporting(c *Context, w http.ResponseWriter, r *http.Request) {
-	if !(c.IsSystemAdmin() && c.App.SessionHasPermissionTo(*c.AppContext.Session(), model.PermissionSysconsoleReadUserManagementUsers)) {
+	if !(c.IsSystemAdmin()) {
 		c.SetPermissionError(model.PermissionSysconsoleReadUserManagementUsers)
 		return
 	}
@@ -73,6 +76,50 @@ func getUserCountForReporting(c *Context, w http.ResponseWriter, r *http.Request
 	}
 }
 
+func startUsersBatchExport(c *Context, w http.ResponseWriter, r *http.Request) {
+	if !(c.IsSystemAdmin()) {
+		c.SetPermissionError(model.PermissionSysconsoleReadUserManagementUsers)
+		return
+	}
+
+	startAt, endAt := model.GetReportDateRange(r.URL.Query().Get("date_range"), time.Now())
+	if err := c.App.StartUsersBatchExport(c.AppContext, startAt, endAt); err != nil {
+		c.Err = err
+		return
+	}
+
+	ReturnStatusOK(w)
+}
+
+func retrieveBatchReportFile(c *Context, w http.ResponseWriter, r *http.Request) {
+	if !(c.IsSystemAdmin()) {
+		c.SetPermissionError(model.PermissionSysconsoleReadUserManagementUsers)
+		return
+	}
+
+	reportId := c.Params.ReportId
+	if !model.IsValidId(reportId) {
+		c.Err = model.NewAppError("retrieveBatchReportFile", "api.retrieveBatchReportFile.invalid_report_id", nil, "", http.StatusBadRequest)
+		return
+	}
+
+	format := r.URL.Query().Get("format")
+	if !model.IsValidReportExportFormat(format) {
+		c.Err = model.NewAppError("retrieveBatchReportFile", "api.retrieveBatchReportFile.invalid_format", nil, "", http.StatusBadRequest)
+		return
+	}
+
+	file, name, err := c.App.RetrieveBatchReport(reportId, format)
+	if err != nil {
+		c.Err = err
+		return
+	}
+	defer file.Close()
+
+	w.Header().Set("Content-Type", "text/csv")
+	http.ServeContent(w, r, name, time.Time{}, file)
+}
+
 func fillReportingBaseOptions(values url.Values) model.ReportingBaseOptions {
 	sortColumn := "Username"
 	if values.Get("sort_column") != "" {