creating flask webapp with sql alchemy
I'm building a small webapp using flask and hosted on PythonAnywhere. The app is made of an Exchange class where several Team classes interact. Each user who logins is related to a specific Team. The app will have no more than 30 connected users at the same time although they will have to get info in real time. There is also an always-on task which will also need to connect to the database.
I'm using sqlalchemy to manage the database connections but I'm constantly getting either (2006, 'MySQL server has gone away') or (2013, 'Lost connection to MySQL server during query'). Therefore I was wondering how I should manage concurrent connections within the app. I tried several configurations such as opening and closing the connections after every call in the flask app or even within every class method but nothing seems to work.
Should I make calls the database only from the flask app using for instance flask-sqlalchemy or are there other ways to achieve this?
python flask sqlalchemy flask-sqlalchemy pythonanywhere
edited Nov 26 '18 at 7:22
petezurich
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
add a comment |
I'm building a small webapp using flask and hosted on PythonAnywhere. The app is made of an Exchange class where several Team classes interact. Each user who logins is related to a specific Team. The app will have no more than 30 connected users at the same time although they will have to get info in real time. There is also an always-on task which will also need to connect to the database.
I'm using sqlalchemy to manage the database connections but I'm constantly getting either (2006, 'MySQL server has gone away') or (2013, 'Lost connection to MySQL server during query'). Therefore I was wondering how I should manage concurrent connections within the app. I tried several configurations such as opening and closing the connections after every call in the flask app or even within every class method but nothing seems to work.
Should I make calls the database only from the flask app using for instance flask-sqlalchemy or are there other ways to achieve this?
python flask sqlalchemy flask-sqlalchemy pythonanywhere
edited Nov 26 '18 at 7:22
petezurich
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15
add a comment |
I'm building a small webapp using flask and hosted on PythonAnywhere. The app is made of an Exchange class where several Team classes interact. Each user who logins is related to a specific Team. The app will have no more than 30 connected users at the same time although they will have to get info in real time. There is also an always-on task which will also need to connect to the database.
I'm using sqlalchemy to manage the database connections but I'm constantly getting either (2006, 'MySQL server has gone away') or (2013, 'Lost connection to MySQL server during query'). Therefore I was wondering how I should manage concurrent connections within the app. I tried several configurations such as opening and closing the connections after every call in the flask app or even within every class method but nothing seems to work.
Should I make calls the database only from the flask app using for instance flask-sqlalchemy or are there other ways to achieve this?
python flask sqlalchemy flask-sqlalchemy pythonanywhere
edited Nov 26 '18 at 7:22
petezurich
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
I'm building a small webapp using flask and hosted on PythonAnywhere. The app is made of an Exchange class where several Team classes interact. Each user who logins is related to a specific Team. The app will have no more than 30 connected users at the same time although they will have to get info in real time. There is also an always-on task which will also need to connect to the database.
I'm using sqlalchemy to manage the database connections but I'm constantly getting either (2006, 'MySQL server has gone away') or (2013, 'Lost connection to MySQL server during query'). Therefore I was wondering how I should manage concurrent connections within the app. I tried several configurations such as opening and closing the connections after every call in the flask app or even within every class method but nothing seems to work.
Should I make calls the database only from the flask app using for instance flask-sqlalchemy or are there other ways to achieve this?
python flask sqlalchemy flask-sqlalchemy pythonanywhere
python flask sqlalchemy flask-sqlalchemy pythonanywhere
edited Nov 26 '18 at 7:22
petezurich
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
edited Nov 26 '18 at 7:22
petezurich
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
edited Nov 26 '18 at 7:22
petezurich
3,61081734
edited Nov 26 '18 at 7:22
petezurich
3,61081734
edited Nov 26 '18 at 7:22
petezurich
3,61081734
3,61081734
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
asked Nov 26 '18 at 7:15
therealcodetherealcode
748
748
So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15
add a comment |
So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15
So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15
add a comment |
1 Answer
1
active
oldest
votes
Your connections are timing out. Tell sqlalchemy to recycle connections after a time that is shorter than the timeout. Like this:
engine = create_engine('mysql+mysqldb://...', pool_recycle=280)
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Your connections are timing out. Tell sqlalchemy to recycle connections after a time that is shorter than the timeout. Like this:
engine = create_engine('mysql+mysqldb://...', pool_recycle=280)
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
add a comment |
Your connections are timing out. Tell sqlalchemy to recycle connections after a time that is shorter than the timeout. Like this:
engine = create_engine('mysql+mysqldb://...', pool_recycle=280)
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
add a comment |
Your connections are timing out. Tell sqlalchemy to recycle connections after a time that is shorter than the timeout. Like this:
engine = create_engine('mysql+mysqldb://...', pool_recycle=280)
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
Your connections are timing out. Tell sqlalchemy to recycle connections after a time that is shorter than the timeout. Like this:
engine = create_engine('mysql+mysqldb://...', pool_recycle=280)
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
answered Nov 26 '18 at 12:52
GlennGlenn
4,71111321
4,71111321
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
add a comment |
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
I did this already although I put 299
– therealcode
Nov 26 '18 at 14:02
add a comment |
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So are you using flask-sqlalchemy right now? Because if you aren't, using it will probably be the solution.
– Joost
Nov 26 '18 at 13:32
Do you mean like moving all database calls from the classes to the web app and use flask-sqlalchemy?
– therealcode
Nov 26 '18 at 14:05
It doesn't matter where you make calls to the database, it matters that you make calls using a Flask-SQLalchemy db. You only need to keep this in mind when initing your database, and if your database is init-ed as Flask-SQLAlchemy db, it will handle all kinds of funky errors and behaviour from there. Read here
– Joost
Nov 26 '18 at 14:15