[MM-55017] Add API method to get users for Admin Reporting (#25499)

* Add store method to get reporting data

* Some store changes

* Added app layer

* Added API call, some miscellaneous fixes

* Fix lint

* Fix serialized check

* Add API docs

* Fix user store tests leaking users

* Fix test

* PR feedback

* Add filtering for role/team/activated user, filter out bot users

* Fix mock

* Fix test

* Oops

* Switch to using struct filter

* More PR feedback

* Fix gen

* Fix test

* Fix API docs

* Fix test

* Fix possible SQL injection, some query optimization

* Fix migrations

* Oops

* Add role to API

* Fix check

* Add Client4 API call for load testing

* Fix test

* Update server/channels/store/storetest/user_store.go

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

* PR feedback

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

server/channels/app/user.go

@@ -24,6 +24,7 @@ import (
 	"github.com/mattermost/mattermost/server/public/shared/i18n"
 	"github.com/mattermost/mattermost/server/public/shared/mlog"
 	"github.com/mattermost/mattermost/server/public/shared/request"
+	pUtils "github.com/mattermost/mattermost/server/public/utils"
 	"github.com/mattermost/mattermost/server/v8/channels/app/email"
 	"github.com/mattermost/mattermost/server/v8/channels/app/imaging"
 	"github.com/mattermost/mattermost/server/v8/channels/app/users"
@@ -2817,3 +2818,36 @@ func (a *App) UserIsFirstAdmin(user *model.User) bool {
 
 	return true
 }
+
+func (a *App) GetUsersForReporting(filter *model.UserReportOptions) ([]*model.UserReport, *model.AppError) {
+	// Don't allow fetching more than 100 users at a time from the normal query endpoint
+	if filter.PageSize <= 0 || filter.PageSize > 100 {
+		return nil, model.NewAppError("GetUsersForReporting", "app.user.get_users_for_reporting.invalid_page_size", nil, "", http.StatusBadRequest)
+	}
+
+	// Validate date range
+	if filter.EndAt > 0 && filter.StartAt > filter.EndAt {
+		return nil, model.NewAppError("GetUsersForReporting", "app.user.get_users_for_reporting.bad_date_range", nil, "", http.StatusBadRequest)
+	}
+
+	return a.getUserReport(filter)
+}
+
+func (a *App) getUserReport(filter *model.UserReportOptions) ([]*model.UserReport, *model.AppError) {
+	// Validate against the columns we allow sorting for
+	if !pUtils.Contains(model.UserReportSortColumns, filter.SortColumn) {
+		return nil, model.NewAppError("GetUsersForReporting", "app.user.get_user_report.invalid_sort_column", nil, "", http.StatusBadRequest)
+	}
+
+	userReportQuery, err := a.Srv().Store().User().GetUserReport(filter)
+	if err != nil {
+		return nil, model.NewAppError("GetUsersForReporting", "app.user.get_user_report.store_error", nil, "", http.StatusInternalServerError).Wrap(err)
+	}
+
+	userReports := make([]*model.UserReport, len(userReportQuery))
+	for i, user := range userReportQuery {
+		userReports[i] = user.ToReport()
+	}
+
+	return userReports, nil
+}