Fixed database inconsistencies introduced by overeager maintenance

maloja/database/sqldb.py

@@ -3,6 +3,7 @@ import json
 import unicodedata
 import math
 from datetime import datetime
+from threading import Lock
 
 from ..globalconf import data_dir
 from .dbcache import cached_wrapper, cached_wrapper_individual, invalidate_entity_cache
@@ -60,6 +61,12 @@ DB['associated_artists'] = sql.Table(
 meta.create_all(engine)
 
 
+
+# adding a scrobble could consist of multiple write operations that sqlite doesn't
+# see as belonging together
+SCROBBLE_LOCK = Lock()
+
+
 # decorator that passes either the provided dbconn, or creates a separate one
 # just for this function call
 def connection_provider(func):
@@ -189,6 +196,8 @@ def add_scrobble(scrobbledict,dbconn=None):
 @connection_provider
 def add_scrobbles(scrobbleslist,dbconn=None):
 
+	with SCROBBLE_LOCK:
+
 		ops = [
 			DB['scrobbles'].insert().values(
 				**scrobble_dict_to_db(s)
@@ -619,6 +628,8 @@ def get_artist(id,dbconn=None):
 
 @runhourly
 def clean_db():
+
+	with SCROBBLE_LOCK:
 		with engine.begin() as conn:
 			#log(f"Database Cleanup...")
 
@@ -658,6 +669,7 @@ def clean_db():
 
 @runmonthly
 def renormalize_names():
+	with SCROBBLE_LOCK:
 		with engine.begin() as conn:
 			rows = conn.execute(DB['artists'].select()).all()