added some comments for handling file creation errors

api/v1/api_files.go

@@ -95,16 +95,27 @@ func (api *API) CreateFileForShow() http.Handler {
 			sendError(w, err)
 			return
 		}
+		// TODO: from here on, in case of an error we should either delete the newly created
+		//       file or at least return the id of the created file so the UI can deal with it.
 
 		refID := "" // TODO: get this from query paremeter
 		job, err := api.importer.CreateJob(showID, file.ID, *srcURI, sess.Username, refID)
 		if err != nil {
-			// shall we remove the file here... thinking...
+			// possible errors:
+			//   - importer.ErrSourceNotSupported -> delete file
+			//   - any error returned by store.GetFile():
+			//     possible reasons for this:
+			//       * connection problem to the store database
+			//       * somebody deleted the file
+			//   - importer.ErrFileNotNew -> leave file
 			sendError(w, err)
 			return
 		}
 		if err = job.Start(context.Background(), 3*time.Hour); err != nil { // TODO: hardcoded value
-			// shall we remove the file here... thinking...
+			// possible errors:
+			//   - importer.ErrAlreadyCanceled -> ??
+			//   - error while creating job workdir -> ??
+			//   - importer.ErrTooManyJobs -> ??
 			sendError(w, err)
 			return
 		}
@@ -120,6 +131,9 @@ func (api *API) CreateFileForShow() http.Handler {
 			<-job.Done()
 		}
 		if file, err = api.store.GetFile(showID, file.ID); err != nil {
+			// possible reasons why this failed:
+			//   - connection problem to the store database
+			//   - somebody deleted the file
 			sendError(w, err)
 			return
 		}