Migrate multiples methods from ChannelStore to return error interface (#14708)

Automatic Merge

app/command_msg.go

@@ -4,11 +4,13 @@
 package app
 
 import (
+	"errors"
 	"strings"
 
 	goi18n "github.com/mattermost/go-i18n/i18n"
 	"github.com/mattermost/mattermost-server/v5/mlog"
 	"github.com/mattermost/mattermost-server/v5/model"
+	"github.com/mattermost/mattermost-server/v5/store"
 )
 
 type msgProvider struct {
@@ -72,7 +74,8 @@ func (me *msgProvider) DoCommand(a *App, args *model.CommandArgs, message string
 
 	targetChannelId := ""
 	if channel, channelErr := a.Srv().Store.Channel().GetByName(args.TeamId, channelName, true); channelErr != nil {
-		if channelErr.Id == "store.sql_channel.get_by_name.missing.app_error" {
+		var nfErr *store.ErrNotFound
+		if errors.As(channelErr, &nfErr) {
 			if !a.SessionHasPermissionTo(args.Session, model.PERMISSION_CREATE_DIRECT_CHANNEL) {
 				return &model.CommandResponse{Text: args.T("api.command_msg.permission.app_error"), ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL}
 			}