On Sun, Jun 3, 2018 at 11:42 PM, rvd <[email protected]> wrote: > Hi Mike, > > Thanks for the quick reply. I am using Version 9.6.6 (RDS). Not using any > proxy. Because this was a rather blocking issue, I have been utilizing a > terrible workaround (namely creating an engine every single request, and > using that session) with some success - obviously not ideal though. I have > tried reducing the pool_recycle parameter to 60 seconds; I came across the > ping thing as well during my research - will give that a try too and let you > know. Thank you a ton again for the suggestions, they are very much > appreciated.
you never need to create engine per request, pooling is turned off entirely using NullPool: http://docs.sqlalchemy.org/en/latest/core/pooling.html#switching-pool-implementations > > rvd > > On Sunday, June 3, 2018 at 7:17:55 PM UTC-7, rvd wrote: >> >> Hi all, >> >> I am writing a Flask API that needs to communicate with many datastores, >> Postgres on AWS RDS being one of them. I want to avoid Flask-SQLAlchemy >> (trying to reduce package dependence); I think the standard SQLAlchemy >> library should suffice. I have described the issue thoroughly here (code is >> here as well). But here is the synopsis. When I use a Session object in my >> app, for the first few requests, it works great. Then, if I wait for a while >> and fire off another request, I get a Psycopg2 error about the server >> closing off the connection unexpectedly. This is rather crippling. I have >> spent a lot of time going through SO, asked in the SQLAlchemy IRC channel, >> and tried many tutorials, and this seems to be a standard valid pattern, so >> I am not sure what is going wrong. Should I not be removing the session? >> Should I be using the @app.teardown_appcontext decorator (it seems that if I >> just remove the sessions myself as I am doing now, I shouldn't have to)? >> Should I be using a connection pool instead (it seems that QueuePool is >> enabled under the hood by default anyway)? If it helps, I am using the >> latest version of all packages, Python 3.6.5, and Postman to send the >> requests to the server, which is running at localhost:5000. Any advice would >> be much appreciated - thanks in advance! >> >> Best, >> rvd > > -- > SQLAlchemy - > The Python SQL Toolkit and Object Relational Mapper > > http://www.sqlalchemy.org/ > > To post example code, please provide an MCVE: Minimal, Complete, and > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > description. > --- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
