Feature/audit certificate upload (#30223)

* feat: Add certificate upload option for audit logging settings

* Commit current changes

* Additions

* MM-62944 Fix fileupload settings not being clickable

* Support for uploading a cert for experimental audit logging cert. Pre cloud implementation in the backend

* Forgot to add new hook

* Add support for setting custom audit log certifcates in Cloud

* Permissions

* I18n

* Change order

* Linter fixes

* Linter fixes, add openapi spec

* additions for openapi

* More openapi fixes because it won't run locally

* Undo, cursor went rogue

* newline fix

* Align types properly

* Fix i18n

* Fix i18n AGAIN

* Fix error

* Update api/v4/source/audit_logging.yaml

---------

Co-authored-by: Harrison Healey <harrisonmhealey@gmail.com>
Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/api4/audit_logging.go

@@ -0,0 +1,84 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package api4
+
+import (
+	"mime/multipart"
+	"net/http"
+
+	"github.com/mattermost/mattermost/server/public/model"
+	"github.com/mattermost/mattermost/server/v8/channels/audit"
+)
+
+func (api *API) InitAuditLogging() {
+	api.BaseRoutes.AuditLogs.Handle("/certificate", api.APISessionRequired(addAuditLogCertificate)).Methods(http.MethodPost)
+	api.BaseRoutes.AuditLogs.Handle("/certificate", api.APISessionRequired(removeAuditLogCertificate)).Methods(http.MethodDelete)
+}
+
+func parseAuditLogCertificateRequest(r *http.Request, maxFileSize int64) (*multipart.FileHeader, *model.AppError) {
+	err := r.ParseMultipartForm(maxFileSize)
+	if err != nil {
+		return nil, model.NewAppError("addAuditLogCertificate", "api.admin.add_certificate.no_file.app_error", nil, "", http.StatusBadRequest).Wrap(err)
+	}
+
+	m := r.MultipartForm
+
+	fileArray, ok := m.File["certificate"]
+	if !ok || len(fileArray) == 0 {
+		return nil, model.NewAppError("addAuditLogCertificate", "api.admin.add_certificate.no_file.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	if len(fileArray) > 1 {
+		return nil, model.NewAppError("addAuditLogCertificate", "api.admin.add_certificate.multiple_files.app_error", nil, "", http.StatusBadRequest)
+	}
+
+	return fileArray[0], nil
+}
+
+func addAuditLogCertificate(c *Context, w http.ResponseWriter, r *http.Request) {
+	c.Logger.Debug("addAuditLogCertificate")
+
+	if !c.App.SessionHasPermissionTo(*c.AppContext.Session(), model.PermissionSysconsoleWriteExperimentalFeatures) {
+		c.SetPermissionError(model.PermissionSysconsoleWriteExperimentalFeatures)
+		return
+	}
+
+	fileData, err := parseAuditLogCertificateRequest(r, *c.App.Config().FileSettings.MaxFileSize)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	auditRec := c.MakeAuditRecord("addAuditLogCertificate", audit.Fail)
+	defer c.LogAuditRec(auditRec)
+	audit.AddEventParameter(auditRec, "filename", fileData.Filename)
+
+	if err := c.App.AddAuditLogCertificate(c.AppContext, fileData); err != nil {
+		c.Err = err
+		return
+	}
+
+	auditRec.Success()
+	ReturnStatusOK(w)
+}
+
+func removeAuditLogCertificate(c *Context, w http.ResponseWriter, r *http.Request) {
+	c.Logger.Debug("removeAuditLogCertificate")
+
+	if !c.App.SessionHasPermissionTo(*c.AppContext.Session(), model.PermissionSysconsoleWriteExperimentalFeatures) {
+		c.SetPermissionError(model.PermissionSysconsoleWriteExperimentalFeatures)
+		return
+	}
+
+	auditRec := c.MakeAuditRecord("removeAuditLogCertificate", audit.Fail)
+	defer c.LogAuditRec(auditRec)
+
+	if err := c.App.RemoveAuditLogCertificate(c.AppContext); err != nil {
+		c.Err = err
+		return
+	}
+
+	auditRec.Success()
+	ReturnStatusOK(w)
+}