cleanup of note (& revisions) content is now postponed and done 48 hours after deleting it. This makes it possible to correct user mistake without having to use a real backup

src/entities/note.js

@@ -104,6 +104,13 @@ class Note extends Entity {
         return await repository.getEntities(`SELECT * FROM attributes WHERE isDeleted = 0 AND noteId = ?`, [this.noteId]);
     }
 
+    /**
+     * @returns {Promise<Attribute[]>} relations targetting this specific note
+     */
+    async getTargetRelations() {
+        return await repository.getEntities("SELECT * FROM attributes WHERE type = 'relation' AND isDeleted = 0 AND value = ?", [this.noteId]);
+    }
+
     /**
      * @param {string} [name] - attribute name to filter
      * @returns {Promise<Attribute[]>} all note's attributes, including inherited ones

src/services/notes.js

@@ -278,11 +278,11 @@ async function deleteNote(branch) {
 
     if (notDeletedBranches.length === 0) {
         note.isDeleted = true;
-        note.content = '';
+        // we don't reset content here, that's postponed and done later to give the user
+        // a chance to correct a mistake
         await note.save();
 
         for (const noteRevision of await note.getRevisions()) {
-            noteRevision.content = '';
             await noteRevision.save();
         }
 
@@ -295,15 +295,36 @@ async function deleteNote(branch) {
             await attribute.save();
         }
 
-        const targetAttributes = await repository.getEntities("SELECT * FROM attributes WHERE type = 'relation' AND isDeleted = 0 AND value = ?", [note.noteId]);
-
-        for (const attribute of targetAttributes) {
+        for (const attribute of await note.getTargetRelations()) {
             attribute.isDeleted = true;
             await attribute.save();
         }
     }
 }
 
+async function cleanupDeletedNotes() {
+    const cutoffDate = new Date(new Date().getTime() - 48 * 3600 * 1000);
+
+    const notesForCleanup = await repository.getEntities("SELECT * FROM notes WHERE isDeleted = 1 AND content != '' AND dateModified <= ?", [dateUtils.dateStr(cutoffDate)]);
+
+    for (const note of notesForCleanup) {
+        note.content = '';
+        await note.save();
+    }
+
+    const notesRevisionsForCleanup = await repository.getEntities("SELECT note_revisions.* FROM notes JOIN note_revisions USING(noteId) WHERE notes.isDeleted = 1 AND note_revisions.content != '' AND notes.dateModified <= ?", [dateUtils.dateStr(cutoffDate)]);
+
+    for (const noteRevision of notesRevisionsForCleanup) {
+        noteRevision.content = '';
+        await noteRevision.save();
+    }
+}
+
+// first cleanup kickoff 5 minutes after startup
+setTimeout(cleanupDeletedNotes, 5 * 60 * 1000);
+
+setInterval(cleanupDeletedNotes, 4 * 3600 * 1000);
+
 module.exports = {
     createNewNote,
     createNote,