no, create_engine() does not connect at all. connections occur when you first call `engine.connect()`. From that point, the behavior of subsequent `engine.connect()` calls depends on connection pool configuration. all connection pools have points at which they continue to establish new connections as the application proceeds, it's just a question of how often and under what circumstances. The default QueuePool will make new connections when it goes into "overflow", as well as when existing connections are invalidated due to connectivity problems or if the pool_recycle timeout is reached.
On Thu, Sep 7, 2023, at 2:34 PM, Steven Schierholz wrote: > That makes sense but doesn't connect only happen once when create_engine() is > called? > > On Thursday, September 7, 2023 at 12:00:35 PM UTC-6 Mike Bayer wrote: >> __ >> the documentation for this pattern is at >> https://docs.sqlalchemy.org/en/20/core/engines.html#generating-dynamic-authentication-tokens >> , and a completely specific example is at >> https://docs.sqlalchemy.org/en/20/dialects/mssql.html#mssql-pyodbc-access-tokens >> . Basically your application needs to have some way to retrieve the >> correct credentials as it runs, and you hook that into the event to populate >> the connect arguments with the correct credentials. >> >> On Thu, Sep 7, 2023, at 1:54 PM, Steven Schierholz wrote: >>> So I have seen some chats here about cred refresh from vault and some >>> suggestions have been to use @event.listens_for(engine, "do_connect") to >>> update creds when the connection is established. My understanding of this >>> is that connecting to the database should only happen once when my flask >>> application starts up, but I need to update the creds without restarting my >>> application so I'm not sure that the event listener will work in my case. >>> >>> Am I understanding that correctly? If so, is there a way to get the right >>> creds to pass to the engine for sqlalchemy every 24 hours when the creds >>> from vault get updated without restarting my application? >>> >>> >>> -- >>> 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 sqlalchemy+...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/sqlalchemy/2de2e3fb-526c-49f7-8780-9ef55a9ad8bcn%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/sqlalchemy/2de2e3fb-526c-49f7-8780-9ef55a9ad8bcn%40googlegroups.com?utm_medium=email&utm_source=footer>. >> > > > -- > 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 sqlalchemy+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sqlalchemy/5c9c5b5f-a84b-41b8-8eb2-c3117fbf50f5n%40googlegroups.com > > <https://groups.google.com/d/msgid/sqlalchemy/5c9c5b5f-a84b-41b8-8eb2-c3117fbf50f5n%40googlegroups.com?utm_medium=email&utm_source=footer>. -- 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 sqlalchemy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/71dcdb8d-2493-403d-83f7-7060041a563c%40app.fastmail.com.
