added possibility to search by attached script returning note ids + some refactorings

src/routes/api/search.js

@@ -1,7 +1,10 @@
 "use strict";
 
 const noteService = require('../../services/notes');
+const repository = require('../../services/repository');
 const noteCacheService = require('../../services/note_cache');
+const log = require('../../services/log');
+const scriptService = require('../../services/script');
 const searchService = require('../../services/search');
 
 async function searchNotes(req) {
@@ -24,7 +27,79 @@ async function saveSearchToNote(req) {
     return { noteId: note.noteId };
 }
 
+async function searchFromNote(req) {
+    const note = await repository.getNote(req.params.noteId);
+
+    if (!note) {
+        return [404, `Note ${req.params.noteId} has not been found.`];
+    }
+
+    if (note.type !== 'search') {
+        return [400, '`Note ${req.params.noteId} is not search note.`']
+    }
+
+    const json = await note.getJsonContent();
+
+    if (!json || !json.searchString) {
+        return [];
+    }
+
+    let noteIds;
+
+    if (json.searchString.startsWith('=')) {
+        const relationName = json.searchString.substr(1).trim();
+
+        noteIds = await searchFromRelation(note, relationName);
+    }
+    else {
+        noteIds = searchService.searchForNoteIds(json.searchString);
+    }
+
+    // we won't return search note's own noteId
+    noteIds = noteIds.filter(noteId => noteId !== note.noteId);
+
+    return noteIds.map(noteCacheService.getNotePath).filter(res => !!res);
+}
+
+async function searchFromRelation(note, relationName) {
+    const scriptNote = await note.getRelationTarget(relationName);
+
+    if (!scriptNote) {
+        log.info(`Search note's relation ${relationName} has not been found.`);
+
+        return [];
+    }
+
+    if (!scriptNote.isJavaScript() || scriptNote.getScriptEnv() !== 'backend') {
+        log.info(`Note ${scriptNote.noteId} is not executable.`);
+
+        return [];
+    }
+
+    if (!note.isContentAvailable) {
+        log.info(`Note ${scriptNote.noteId} is not available outside of protected session.`);
+
+        return [];
+    }
+
+    const result = await scriptService.executeNote(scriptNote, { originEntity: note });
+
+    if (!Array.isArray(result)) {
+        log.info(`Result from ${scriptNote.noteId} is not an array.`);
+
+        return [];
+    }
+
+    if (result.length === 0) {
+        return [];
+    }
+
+    // we expect either array of noteIds (strings) or notes, in that case we extract noteIds ourselves
+    return typeof result[0] === 'string' ? result : result.map(item => item.noteId);
+}
+
 module.exports = {
     searchNotes,
-    saveSearchToNote
+    saveSearchToNote,
+    searchFromNote
 };