diff --git a/src/scheduling/fallback.py b/src/scheduling/fallback.py
index 6a6133aa6c62e1b745776d5910d780bdab2088ad..bcf669f4cd9bd3c0b052428e65210cdde531d8ff 100644
--- a/src/scheduling/fallback.py
+++ b/src/scheduling/fallback.py
@@ -138,7 +138,8 @@ class FallbackManager:
if fallback_type != self.state.get("previous_fallback_type"):
timeslot = self.state["timeslot"]
if timeslot:
- DB.session.merge(timeslot)
+ with DB.Session() as session:
+ session.merge(timeslot)
self.engine.event_dispatcher.on_fallback_active(timeslot, fallback_type)
diff --git a/src/scheduling/models.py b/src/scheduling/models.py
index f5a6b487e61aca67124071155197955511ef49b0..fdb5ebdcebcc99d0dd5cf6638b57b91e871dded8 100644
--- a/src/scheduling/models.py
+++ b/src/scheduling/models.py
@@ -17,6 +17,7 @@
# along with this program. If not, see <http://www.gnu.org/licenses/>.
+import contextlib
import sys
import time
import logging
@@ -24,6 +25,7 @@ import datetime
import sqlalchemy as sa
+import sqlalchemy
from sqlalchemy import BigInteger, Boolean, Column, DateTime, Integer, String, ForeignKey, ColumnDefault
from sqlalchemy.orm import scoped_session
from sqlalchemy.orm import sessionmaker
@@ -40,14 +42,35 @@ config = AuraConfig()
engine = sa.create_engine(config.get_database_uri())
Base = declarative_base()
Base.metadata.bind = engine
+__sqlalchemy_version = tuple(int(item) for item in sqlalchemy.__version__.split(".")[:2])
+
class DB():
session_factory = sessionmaker(bind=engine)
Session = scoped_session(session_factory)
- session = Session()
Model = Base
+# Monkey-patch the above DB.Session generator for SQLAlchemy before v1.4.
+# Such older versions of SQLAlchemy do not support contexts.
+if __sqlalchemy_version < (1, 4):
+ @contextlib.contextmanager
+ def get_session_context():
+ """ provide a context for a session
+
+ This context is the same as the one provided by a "scoped_session" in SQLAlchemy v1.4 or
+ later.
+
+ see https://docs.sqlalchemy.org/en/13/orm/session_basics.html#when-do-i-construct-a-session-when-do-i-commit-it-and-when-do-i-close-it
+ """
+ session = scoped_session(DB.session_factory)
+ try:
+ yield session
+ finally:
+ session.close()
+
+ DB.Session = get_session_context
+
class AuraDatabaseModel():
"""
@@ -69,29 +92,32 @@ class AuraDatabaseModel():
"""
Store to the database
"""
- if add:
- DB.session.add(self)
- else:
- DB.session.merge(self)
- if commit:
- DB.session.commit()
+ with DB.Session() as session:
+ if add:
+ session.add(self)
+ else:
+ session.merge(self)
+ if commit:
+ session.commit()
def delete(self, commit=False):
"""
Delete from the database
"""
- DB.session.delete(self)
- if commit:
- DB.session.commit()
+ with DB.Session() as session:
+ session.delete(self)
+ if commit:
+ session.commit()
def refresh(self):
"""
Refreshes the currect record
"""
- DB.session.expire(self)
- DB.session.refresh(self)
+ with DB.Session() as session:
+ session.expire(self)
+ session.refresh(self)
def _asdict(self):
@@ -132,7 +158,8 @@ class AuraDatabaseModel():
"""
Base.metadata.drop_all()
Base.metadata.create_all()
- DB.session.commit()
+ with DB.Session() as session:
+ session.commit()
if systemexit:
sys.exit(0)
@@ -223,7 +250,12 @@ class Timeslot(DB.Model, AuraDatabaseModel):
Args:
date_time (datetime): date and time when the timeslot starts
"""
- return DB.session.query(Timeslot).filter(Timeslot.timeslot_start == date_time).first()
+ with DB.Session() as session:
+ return (
+ session.query(Timeslot)
+ .filter(Timeslot.timeslot_start == date_time)
+ .first()
+ )
@staticmethod
@@ -238,10 +270,13 @@ class Timeslot(DB.Model, AuraDatabaseModel):
Returns:
([Timeslot]): List of timeslots
"""
- timeslots = DB.session.query(Timeslot).\
- filter(Timeslot.timeslot_start >= date_from).\
- order_by(Timeslot.timeslot_start).all()
- return timeslots
+ with DB.Session() as session:
+ return (
+ session.query(Timeslot)
+ .filter(Timeslot.timeslot_start >= date_from)
+ .order_by(Timeslot.timeslot_start)
+ .all()
+ )
def set_active_entry(self, entry):
@@ -355,7 +390,8 @@ class Playlist(DB.Model, AuraDatabaseModel):
# """
# Fetches all entries
# """
- # all_entries = DB.session.query(Playlist).filter(Playlist.fallback_type == 0).all()
+ # with DB.Session() as session:
+ # all_entries = session.query(Playlist).filter(Playlist.fallback_type == 0).all()
# cnt = 0
# for entry in all_entries:
@@ -381,7 +417,12 @@ class Playlist(DB.Model, AuraDatabaseModel):
Exception: In case there a inconsistent database state, such es multiple playlists for given date/time.
"""
playlist = None
- playlists = DB.session.query(Playlist).filter(Playlist.timeslot_start == start_date).all()
+ with DB.Session() as session:
+ playlists = (
+ session.query(Playlist)
+ .filter(Playlist.timeslot_start == start_date)
+ .all()
+ )
for p in playlists:
if p.playlist_id == playlist_id:
@@ -401,7 +442,13 @@ class Playlist(DB.Model, AuraDatabaseModel):
Returns:
(Array<Playlist>): An array holding the playlists
"""
- return DB.session.query(Playlist).filter(Playlist.playlist_id == playlist_id).order_by(Playlist.timeslot_start).all()
+ with DB.Session() as session:
+ return (
+ session.query(Playlist)
+ .filter(Playlist.playlist_id == playlist_id)
+ .order_by(Playlist.timeslot_start)
+ .all()
+ )
@staticmethod
@@ -409,10 +456,11 @@ class Playlist(DB.Model, AuraDatabaseModel):
"""
Checks if the given is empty
"""
- try:
- return not DB.session.query(Playlist).one_or_none()
- except sa.orm.exc.MultipleResultsFound:
- return False
+ with DB.Session() as session:
+ try:
+ return not session.query(Playlist).one_or_none()
+ except sa.orm.exc.MultipleResultsFound:
+ return False
@hybrid_property
@@ -509,26 +557,37 @@ class PlaylistEntry(DB.Model, AuraDatabaseModel):
"""
Selects one entry identified by `playlist_id` and `entry_num`.
"""
- return DB.session.query(PlaylistEntry).filter(PlaylistEntry.artificial_playlist_id == artificial_playlist_id, PlaylistEntry.entry_num == entry_num).first()
+ with DB.Session() as session:
+ return (
+ session.query(PlaylistEntry)
+ .filter(PlaylistEntry.entry_num == entry_num)
+ .filter(PlaylistEntry.artificial_playlist_id == artificial_playlist_id)
+ .first()
+ )
@staticmethod
def delete_entry(artificial_playlist_id, entry_num):
"""
Deletes the playlist entry and associated metadata.
"""
- entry = PlaylistEntry.select_playlistentry_for_playlist(artificial_playlist_id, entry_num)
- metadata = PlaylistEntryMetaData.select_metadata_for_entry(entry.artificial_id)
- metadata.delete()
- entry.delete()
- DB.session.commit()
+ with DB.Session() as session:
+ entry = PlaylistEntry.select_playlistentry_for_playlist(artificial_playlist_id, entry_num)
+ metadata = PlaylistEntryMetaData.select_metadata_for_entry(entry.artificial_id)
+ metadata.delete()
+ entry.delete()
+ session.commit()
@staticmethod
def count_entries(artificial_playlist_id):
"""
Returns the count of all entries.
"""
- result = DB.session.query(PlaylistEntry).filter(PlaylistEntry.artificial_playlist_id == artificial_playlist_id).count()
- return result
+ with DB.Session() as session:
+ return (
+ session.query(PlaylistEntry)
+ .filter(PlaylistEntry.artificial_playlist_id == artificial_playlist_id)
+ .count()
+ )
@hybrid_property
def entry_end(self):
@@ -633,6 +692,9 @@ class PlaylistEntryMetaData(DB.Model, AuraDatabaseModel):
@staticmethod
def select_metadata_for_entry(artificial_playlistentry_id):
- return DB.session.query(PlaylistEntryMetaData).filter(PlaylistEntryMetaData.artificial_entry_id == artificial_playlistentry_id).first()
-
-
+ with DB.Session() as session:
+ return (
+ session.query(PlaylistEntryMetaData)
+ .filter(PlaylistEntryMetaData.artificial_entry_id == artificial_playlistentry_id)
+ .first()
+ )