Django Database Connection Autoreconnect
This library monkeypatches
that when a database operation fails because the underlying TCP connection was
already closed, it first tried to reconnect, instead of immediately raising
Why is this useful?
I use HAProxy as a load-balancer in front of my PostgreSQL databases all
the time, sometimes in addition to
pgbouncer. Even though you can mostly
prevent surprises by enabling TCP keep-alive packets through tcpka,
clitcpka and srvtcpka, I still encounter situations where the
underlying TCP connection has been closed through the load-balancer. Most often
this results in
django.db.utils.OperationalError: server closed the connection unexpectedly This probably means the server terminated abnormally before or while processing the request.
This library patches Django such that it try to reconnect once before failing.
Another application of this is when using Hashicorp Vault, where credentials for a database connection can expire at any time and then need to be refreshed from Vault.
How to install?
Just pull the library in using
pip install django-dbconn-retry. Then add
INSTALLED_APPS in your
The library provides an interface for other code to plug into the process to, for example, allow 12factor-vault to refresh the database credentials before the code tries to reestablish the database connection. These are implemented using Django Signals.
||Installs a hook of the type
||Installs a hook of the type
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