""" Universal Metadata Cache — caches all Spotify and iTunes API responses. Stores full JSON responses alongside structured queryable fields for browsing. Transparent to callers: check cache before API call, store after success. """ import json import logging import threading from datetime import datetime from typing import Optional, Dict, List, Tuple logger = logging.getLogger(__name__) # Singleton _cache_instance = None _cache_lock = threading.Lock() def get_metadata_cache(): """Get or create the singleton MetadataCache instance.""" global _cache_instance if _cache_instance is None: with _cache_lock: if _cache_instance is None: _cache_instance = MetadataCache() return _cache_instance class MetadataCache: """Caches Spotify and iTunes API responses with structured fields + raw JSON.""" def __init__(self): # Tables are created by MusicDatabase migration — we just use get_database() pass def _get_db(self): from database.music_database import get_database return get_database() # ─── Entity Methods ─────────────────────────────────────────────── def get_entity(self, source: str, entity_type: str, entity_id: str) -> Optional[dict]: """Look up a cached entity. Returns parsed raw_json dict on hit, None on miss.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() cursor.execute(""" SELECT id, raw_json, updated_at, ttl_days FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ? """, (source, entity_type, entity_id)) row = cursor.fetchone() if row: # Inline TTL check — don't serve stale data try: updated = datetime.fromisoformat(row['updated_at']) age_days = (datetime.now() - updated).days if age_days > (row['ttl_days'] or 30): cursor.execute("DELETE FROM metadata_cache_entities WHERE id = ?", (row['id'],)) conn.commit() return None except (ValueError, TypeError): pass # Touch: update access stats cursor.execute(""" UPDATE metadata_cache_entities SET last_accessed_at = CURRENT_TIMESTAMP, access_count = access_count + 1 WHERE id = ? """, (row['id'],)) conn.commit() return json.loads(row['raw_json']) return None finally: conn.close() except Exception as e: logger.debug(f"Cache lookup error ({source}/{entity_type}/{entity_id}): {e}") return None def store_entity(self, source: str, entity_type: str, entity_id: str, raw_data: dict) -> None: """Store an entity in the cache. Extracts structured fields from raw_data.""" if not entity_id or not raw_data: return try: fields = self._extract_fields(source, entity_type, raw_data) raw_json = json.dumps(raw_data, default=str) db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() cursor.execute(""" INSERT OR REPLACE INTO metadata_cache_entities (source, entity_type, entity_id, name, image_url, external_urls, genres, popularity, followers, artist_name, artist_id, release_date, total_tracks, album_type, label, album_name, album_id, duration_ms, track_number, disc_number, explicit, isrc, preview_url, raw_json, updated_at, last_accessed_at, access_count) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, COALESCE((SELECT access_count FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ?), 0) + 1) """, ( source, entity_type, entity_id, fields.get('name', ''), fields.get('image_url'), fields.get('external_urls'), fields.get('genres'), fields.get('popularity'), fields.get('followers'), fields.get('artist_name'), fields.get('artist_id'), fields.get('release_date'), fields.get('total_tracks'), fields.get('album_type'), fields.get('label'), fields.get('album_name'), fields.get('album_id'), fields.get('duration_ms'), fields.get('track_number'), fields.get('disc_number'), fields.get('explicit'), fields.get('isrc'), fields.get('preview_url'), raw_json, source, entity_type, entity_id, )) conn.commit() finally: conn.close() except Exception as e: logger.debug(f"Cache store error ({source}/{entity_type}/{entity_id}): {e}") def store_entities_bulk(self, source: str, entity_type: str, items: List[Tuple[str, dict]], skip_if_exists: bool = False) -> None: """Store multiple entities at once. items = [(entity_id, raw_data), ...] Args: skip_if_exists: If True, don't overwrite existing entries. Use this for opportunistic caching of simplified data (e.g. from list endpoints) to avoid replacing richer data from detail endpoints. """ if not items: return try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() for entity_id, raw_data in items: if not entity_id or not raw_data: continue if skip_if_exists: cursor.execute(""" SELECT 1 FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ? """, (source, entity_type, entity_id)) if cursor.fetchone(): continue fields = self._extract_fields(source, entity_type, raw_data) raw_json = json.dumps(raw_data, default=str) cursor.execute(""" INSERT OR REPLACE INTO metadata_cache_entities (source, entity_type, entity_id, name, image_url, external_urls, genres, popularity, followers, artist_name, artist_id, release_date, total_tracks, album_type, label, album_name, album_id, duration_ms, track_number, disc_number, explicit, isrc, preview_url, raw_json, updated_at, last_accessed_at, access_count) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP, COALESCE((SELECT access_count FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ?), 0) + 1) """, ( source, entity_type, entity_id, fields.get('name', ''), fields.get('image_url'), fields.get('external_urls'), fields.get('genres'), fields.get('popularity'), fields.get('followers'), fields.get('artist_name'), fields.get('artist_id'), fields.get('release_date'), fields.get('total_tracks'), fields.get('album_type'), fields.get('label'), fields.get('album_name'), fields.get('album_id'), fields.get('duration_ms'), fields.get('track_number'), fields.get('disc_number'), fields.get('explicit'), fields.get('isrc'), fields.get('preview_url'), raw_json, source, entity_type, entity_id, )) conn.commit() finally: conn.close() except Exception as e: logger.debug(f"Cache bulk store error ({source}/{entity_type}): {e}") def get_entities_batch(self, source: str, entity_type: str, entity_ids: List[str]) -> Tuple[Dict[str, dict], List[str]]: """Batch cache lookup. Returns (found_dict, missing_ids).""" found = {} missing = [] if not entity_ids: return found, missing try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() # Batch query in chunks of 500 to avoid SQLite variable limit for i in range(0, len(entity_ids), 500): chunk = entity_ids[i:i + 500] placeholders = ','.join('?' * len(chunk)) cursor.execute(f""" SELECT entity_id, raw_json FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id IN ({placeholders}) """, [source, entity_type] + chunk) for row in cursor.fetchall(): found[row['entity_id']] = json.loads(row['raw_json']) # Touch all found entries if found: found_in_chunk = [eid for eid in chunk if eid in found] if found_in_chunk: ph2 = ','.join('?' * len(found_in_chunk)) cursor.execute(f""" UPDATE metadata_cache_entities SET last_accessed_at = CURRENT_TIMESTAMP, access_count = access_count + 1 WHERE source = ? AND entity_type = ? AND entity_id IN ({ph2}) """, [source, entity_type] + found_in_chunk) conn.commit() finally: conn.close() missing = [eid for eid in entity_ids if eid not in found] except Exception as e: logger.debug(f"Cache batch lookup error: {e}") missing = entity_ids return found, missing # ─── Search Cache Methods ───────────────────────────────────────── def get_search_results(self, source: str, search_type: str, query: str, limit: int) -> Optional[List[dict]]: """Look up cached search results. Returns list of raw_json dicts or None.""" normalized = query.strip().lower() if not normalized: return None try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() cursor.execute(""" SELECT id, result_ids, created_at FROM metadata_cache_searches WHERE source = ? AND search_type = ? AND query_normalized = ? AND search_limit = ? """, (source, search_type, normalized, limit)) row = cursor.fetchone() if not row: return None # Check TTL (7 days for searches) try: created = datetime.fromisoformat(row['created_at']) age_days = (datetime.now() - created).days if age_days > 7: # Expired — delete and return miss cursor.execute("DELETE FROM metadata_cache_searches WHERE id = ?", (row['id'],)) conn.commit() return None except (ValueError, TypeError): pass # Touch search entry cursor.execute(""" UPDATE metadata_cache_searches SET last_accessed_at = CURRENT_TIMESTAMP, access_count = access_count + 1 WHERE id = ? """, (row['id'],)) conn.commit() # Resolve entity IDs to full data result_ids = json.loads(row['result_ids']) if not result_ids: return [] results = [] for eid in result_ids: cursor.execute(""" SELECT raw_json FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ? """, (source, search_type, eid)) erow = cursor.fetchone() if erow: results.append(json.loads(erow['raw_json'])) # Only return if we found all (or most) entries — partial results are unreliable if len(results) >= len(result_ids) * 0.8: return results return None finally: conn.close() except Exception as e: logger.debug(f"Search cache lookup error ({source}/{search_type}/{query}): {e}") return None def store_search_results(self, source: str, search_type: str, query: str, limit: int, entity_ids: List[str]) -> None: """Store search result mapping. Individual entities should already be stored.""" normalized = query.strip().lower() if not normalized or not entity_ids: return try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() cursor.execute(""" INSERT OR REPLACE INTO metadata_cache_searches (source, search_type, query_normalized, query_original, result_ids, result_count, search_limit, last_accessed_at) VALUES (?, ?, ?, ?, ?, ?, ?, CURRENT_TIMESTAMP) """, ( source, search_type, normalized, query.strip(), json.dumps(entity_ids), len(entity_ids), limit, )) conn.commit() finally: conn.close() except Exception as e: logger.debug(f"Search cache store error ({source}/{search_type}/{query}): {e}") # ─── Browsing (for UI) ──────────────────────────────────────────── def browse(self, entity_type: str, source: str = None, search: str = None, sort: str = 'last_accessed_at', sort_dir: str = 'desc', offset: int = 0, limit: int = 48) -> dict: """Paginated browse of cached entities for the UI.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() where_clauses = ['entity_type = ?'] params = [entity_type] # Exclude pseudo-entities like album_id_tracks and track_id_features where_clauses.append(r"entity_id NOT LIKE '%\_tracks' ESCAPE '\'") where_clauses.append(r"entity_id NOT LIKE '%\_features' ESCAPE '\'") if source: where_clauses.append('source = ?') params.append(source) if search: search_term = f'%{search}%' where_clauses.append('(name LIKE ? OR artist_name LIKE ? OR album_name LIKE ?)') params.extend([search_term, search_term, search_term]) where_sql = ' AND '.join(where_clauses) # Count total cursor.execute(f"SELECT COUNT(*) as cnt FROM metadata_cache_entities WHERE {where_sql}", params) total = cursor.fetchone()['cnt'] # Validate sort column valid_sorts = {'last_accessed_at', 'created_at', 'access_count', 'name', 'popularity', 'updated_at'} if sort not in valid_sorts: sort = 'last_accessed_at' direction = 'ASC' if sort_dir == 'asc' else 'DESC' cursor.execute(f""" SELECT id, source, entity_type, entity_id, name, image_url, genres, popularity, followers, artist_name, artist_id, release_date, total_tracks, album_type, label, album_name, album_id, duration_ms, track_number, disc_number, explicit, isrc, preview_url, external_urls, created_at, updated_at, last_accessed_at, access_count FROM metadata_cache_entities WHERE {where_sql} ORDER BY {sort} {direction} LIMIT ? OFFSET ? """, params + [limit, offset]) items = [] for row in cursor.fetchall(): item = dict(row) # Parse JSON fields for the UI for json_field in ('genres', 'external_urls'): if item.get(json_field): try: item[json_field] = json.loads(item[json_field]) except (json.JSONDecodeError, TypeError): pass items.append(item) return {'items': items, 'total': total, 'offset': offset, 'limit': limit} finally: conn.close() except Exception as e: logger.error(f"Cache browse error: {e}") return {'items': [], 'total': 0, 'offset': offset, 'limit': limit} def get_entity_detail(self, source: str, entity_type: str, entity_id: str) -> Optional[dict]: """Get full entity detail including parsed raw_json for the detail modal.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() cursor.execute(""" SELECT * FROM metadata_cache_entities WHERE source = ? AND entity_type = ? AND entity_id = ? """, (source, entity_type, entity_id)) row = cursor.fetchone() if not row: return None # Touch cursor.execute(""" UPDATE metadata_cache_entities SET last_accessed_at = CURRENT_TIMESTAMP, access_count = access_count + 1 WHERE id = ? """, (row['id'],)) conn.commit() item = dict(row) # Parse JSON fields for json_field in ('genres', 'external_urls', 'raw_json'): if item.get(json_field): try: item[json_field] = json.loads(item[json_field]) except (json.JSONDecodeError, TypeError): pass return item finally: conn.close() except Exception as e: logger.error(f"Cache detail error: {e}") return None # ─── Stats ──────────────────────────────────────────────────────── def get_stats(self) -> dict: """Get cache statistics for the dashboard tool card and modal stats bar.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() stats = { 'artists': {'spotify': 0, 'itunes': 0}, 'albums': {'spotify': 0, 'itunes': 0}, 'tracks': {'spotify': 0, 'itunes': 0}, 'searches': 0, 'total_entries': 0, 'total_hits': 0, 'oldest': None, 'newest': None, } # Count by type and source (exclude pseudo-entities like _tracks, _features) cursor.execute(r""" SELECT entity_type, source, COUNT(*) as cnt, SUM(access_count) as hits FROM metadata_cache_entities WHERE entity_id NOT LIKE '%\_tracks' ESCAPE '\' AND entity_id NOT LIKE '%\_features' ESCAPE '\' GROUP BY entity_type, source """) type_key_map = {'artist': 'artists', 'album': 'albums', 'track': 'tracks'} for row in cursor.fetchall(): et = type_key_map.get(row['entity_type']) src = row['source'] if et and et in stats and src in stats[et]: stats[et][src] = row['cnt'] stats['total_entries'] += row['cnt'] stats['total_hits'] += (row['hits'] or 0) # Search count cursor.execute("SELECT COUNT(*) as cnt FROM metadata_cache_searches") stats['searches'] = cursor.fetchone()['cnt'] # Oldest and newest cursor.execute("SELECT MIN(created_at) as oldest, MAX(created_at) as newest FROM metadata_cache_entities") row = cursor.fetchone() if row: stats['oldest'] = row['oldest'] stats['newest'] = row['newest'] return stats finally: conn.close() except Exception as e: logger.error(f"Cache stats error: {e}") return { 'artists': {'spotify': 0, 'itunes': 0}, 'albums': {'spotify': 0, 'itunes': 0}, 'tracks': {'spotify': 0, 'itunes': 0}, 'searches': 0, 'total_entries': 0, 'total_hits': 0, 'oldest': None, 'newest': None, } # ─── Maintenance ────────────────────────────────────────────────── def evict_expired(self) -> int: """Delete entries that have exceeded their TTL. Returns count of evicted entries.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() # Entities cursor.execute(""" DELETE FROM metadata_cache_entities WHERE julianday('now') - julianday(updated_at) > ttl_days """) entity_count = cursor.rowcount # Searches cursor.execute(""" DELETE FROM metadata_cache_searches WHERE julianday('now') - julianday(created_at) > ttl_days """) search_count = cursor.rowcount conn.commit() total = entity_count + search_count if total > 0: logger.info(f"Evicted {total} expired cache entries ({entity_count} entities, {search_count} searches)") return total finally: conn.close() except Exception as e: logger.error(f"Cache eviction error: {e}") return 0 def clear(self, source: str = None, entity_type: str = None) -> int: """Clear cache entries. Optional filters by source and/or entity_type.""" try: db = self._get_db() conn = db._get_connection() try: cursor = conn.cursor() # Clear entities where_parts = [] params = [] if source: where_parts.append('source = ?') params.append(source) if entity_type: where_parts.append('entity_type = ?') params.append(entity_type) if where_parts: where_sql = ' AND '.join(where_parts) cursor.execute(f"DELETE FROM metadata_cache_entities WHERE {where_sql}", params) else: cursor.execute("DELETE FROM metadata_cache_entities") entity_count = cursor.rowcount # Clear searches (match source and entity_type → search_type) search_where = [] search_params = [] if source: search_where.append('source = ?') search_params.append(source) if entity_type: search_where.append('search_type = ?') search_params.append(entity_type) if search_where: cursor.execute(f"DELETE FROM metadata_cache_searches WHERE {' AND '.join(search_where)}", search_params) else: cursor.execute("DELETE FROM metadata_cache_searches") search_count = cursor.rowcount conn.commit() total = entity_count + search_count logger.info(f"Cleared {total} cache entries (source={source}, type={entity_type})") return total finally: conn.close() except Exception as e: logger.error(f"Cache clear error: {e}") return 0 # ─── Field Extraction ───────────────────────────────────────────── def _extract_fields(self, source: str, entity_type: str, raw_data: dict) -> dict: """Extract structured queryable fields from a raw API response.""" if source == 'spotify': return self._extract_spotify_fields(entity_type, raw_data) elif source == 'itunes': return self._extract_itunes_fields(entity_type, raw_data) return {'name': str(raw_data.get('name', raw_data.get('trackName', '')))} def _extract_spotify_fields(self, entity_type: str, data: dict) -> dict: """Extract fields from Spotify API response.""" fields = {} if entity_type == 'artist': fields['name'] = data.get('name', '') fields['genres'] = json.dumps(data.get('genres', [])) fields['popularity'] = data.get('popularity', 0) followers = data.get('followers') fields['followers'] = followers.get('total', 0) if isinstance(followers, dict) else 0 images = data.get('images', []) fields['image_url'] = images[0]['url'] if images else None fields['external_urls'] = json.dumps(data.get('external_urls', {})) elif entity_type == 'album': fields['name'] = data.get('name', '') artists = data.get('artists', []) if artists: fields['artist_name'] = artists[0].get('name', '') fields['artist_id'] = artists[0].get('id', '') fields['release_date'] = data.get('release_date', '') fields['total_tracks'] = data.get('total_tracks', 0) fields['album_type'] = data.get('album_type', 'album') fields['label'] = data.get('label', '') images = data.get('images', []) fields['image_url'] = images[0]['url'] if images else None fields['genres'] = json.dumps(data.get('genres', [])) fields['external_urls'] = json.dumps(data.get('external_urls', {})) elif entity_type == 'track': fields['name'] = data.get('name', '') artists = data.get('artists', []) if artists: fields['artist_name'] = artists[0].get('name', '') fields['artist_id'] = artists[0].get('id', '') album = data.get('album', {}) fields['album_name'] = album.get('name', '') fields['album_id'] = album.get('id', '') album_images = album.get('images', []) fields['image_url'] = album_images[0]['url'] if album_images else None fields['duration_ms'] = data.get('duration_ms', 0) fields['track_number'] = data.get('track_number') fields['disc_number'] = data.get('disc_number', 1) fields['explicit'] = 1 if data.get('explicit') else 0 fields['popularity'] = data.get('popularity', 0) ext_ids = data.get('external_ids', {}) fields['isrc'] = ext_ids.get('isrc') if isinstance(ext_ids, dict) else None fields['preview_url'] = data.get('preview_url') fields['external_urls'] = json.dumps(data.get('external_urls', {})) return fields def _extract_itunes_fields(self, entity_type: str, data: dict) -> dict: """Extract fields from iTunes API response.""" fields = {} def _upscale_artwork(url): """Convert iTunes 100x100 artwork to 600x600.""" if url and '100x100' in url: return url.replace('100x100', '600x600') return url if entity_type == 'artist': fields['name'] = data.get('artistName', '') genre = data.get('primaryGenreName', '') fields['genres'] = json.dumps([genre] if genre else []) fields['popularity'] = 0 fields['followers'] = 0 fields['image_url'] = _upscale_artwork(data.get('artworkUrl100')) urls = {} if data.get('artistViewUrl'): urls['itunes'] = data['artistViewUrl'] fields['external_urls'] = json.dumps(urls) elif entity_type == 'album': fields['name'] = data.get('collectionName', '') fields['artist_name'] = data.get('artistName', '') fields['artist_id'] = str(data.get('artistId', '')) fields['release_date'] = data.get('releaseDate', '')[:10] if data.get('releaseDate') else '' fields['total_tracks'] = data.get('trackCount', 0) # Infer album type from track count tc = data.get('trackCount', 0) if tc <= 3: fields['album_type'] = 'single' elif tc <= 6: fields['album_type'] = 'ep' else: fields['album_type'] = 'album' fields['image_url'] = _upscale_artwork(data.get('artworkUrl100')) urls = {} if data.get('collectionViewUrl'): urls['itunes'] = data['collectionViewUrl'] fields['external_urls'] = json.dumps(urls) elif entity_type == 'track': fields['name'] = data.get('trackName', '') fields['artist_name'] = data.get('artistName', '') fields['artist_id'] = str(data.get('artistId', '')) fields['album_name'] = data.get('collectionName', '') fields['album_id'] = str(data.get('collectionId', '')) fields['image_url'] = _upscale_artwork(data.get('artworkUrl100')) fields['duration_ms'] = data.get('trackTimeMillis', 0) fields['track_number'] = data.get('trackNumber') fields['disc_number'] = data.get('discNumber', 1) fields['explicit'] = 1 if data.get('trackExplicitness') == 'explicit' else 0 fields['preview_url'] = data.get('previewUrl') urls = {} if data.get('trackViewUrl'): urls['itunes'] = data['trackViewUrl'] fields['external_urls'] = json.dumps(urls) return fields