def session_scope(self):
session = Session()
try:
yield session
session.commit()
except:
session.rollback()
raise
finally:
session.close()
def __str__(self):
return f'Reaction[id={self.id}, seen_date={self.seen_date}, reaction={self.reaction}, user={self.user}, quote_id={self.quote}]'
if __name__ == '__main__':
Base.metadata.create_all(engine)
session = Session()
user = User('3649028588457703', 'DAILY')
session.add(user)
quote = Quote(
"If you want to achieve greatness stop asking for permission.",
"Anonymous")
session.add(quote)
session.commit()
user_quote = Reaction('3649028588457703', quote.id, 'LIKE')
session.add(user_quote)
session.commit()
session.close()
print("=== Now querying data ===")
session = Session()
users = session.query(User).all()
for user in users:
print(user)
quotes = session.query(Quote).all()
for quote in quotes:
print(quote)
reactions = session.query(Quote.text).join(Reaction) \
.filter(Reaction.reaction == 'LIKE')
for reaction in reactions:
print(reaction)
class Context:
def __init__(self):
Base.metadata.create_all(engine)
self.session = Session()
def getAdById(self, adId):
return self.session.query(Ad).get(adId)
def getAdByTitle(self, title):
return self.session.query(Ad).filter_by(title=title).one_or_none()
def getAdsByTags(self, tags):
return self.session.query(Ad).filter(Ad.hiddenTags.any(Tag.value.in_(tags))).all()
def addAd(self, ad):
self._adTags(ad)
try:
self.session.commit()
self.session.add(ad)
self.session.commit()
return ad
except exc.SQLAlchemyError:
print("Context: cannot create ad: ", ad)
return None
def getAds(self, limit, offset=0):
return self.session.query(Ad).limit(limit).offset(offset).all()
def updateAd(self, adId, updated):
fromDb = self.getAdById(adId)
if fromDb is None:
return None
self._removeTags(fromDb)
self._adTags(updated)
try:
fromDb.update(updated)
self.session.commit()
return fromDb
except exc.SQLAlchemyError:
print("Context: cannot remove ad: ", fromDb)
return None
def _adTags(self, ad):
try:
for tag in ad.tags:
self.session.add(tag)
except exc.SQLAlchemyError:
print("Context: cannot add hidden tags: ", ad.tags)
return None
try:
for tag in ad.hiddenTags:
self.session.add(tag)
except exc.SQLAlchemyError:
print("Context: cannot add hidden tags: ", ad.hiddenTags)
def _removeTags(self, ad):
try:
for tag in ad.tags:
self.session.query(ad_tags_association).filter_by(tag_id=tag.id).delete()
self.session.delete(tag)
self.session.commit()
except exc.SQLAlchemyError:
print("Context: cannot delete tags: ", ad.tags)
return None
try:
for tag in ad.hiddenTags:
self.session.query(hidden_ad_tags_association).filter_by(tag_id=tag.id).delete()
self.session.delete(tag)
self.session.commit()
except exc.SQLAlchemyError:
print("Context: cannot delete hidden tags: ", ad.hiddenTags)
def removeAd(self, adId):
fromDb = self.getAdById(adId)
if fromDb is None:
return False
self._removeTags(fromDb)
try:
self.session.commit()
self.session.delete(fromDb)
self.session.commit()
return True
except exc.SQLAlchemyError:
print("Context: cannot delete ad: ", fromDb)
return False
def getTagById(self, tagId):
return self.session.query(Tag).get(tagId)
def getTagByValue(self, value):
return self.session.query(Tag).filter_by(value=value).first()
def addTag(self, tag):
self.session.add(tag)
self.session.commit()
def __del__(self):
try:
self.session.close()
except AttributeError as err:
print(err)