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fix links, change syntax highlighting theme

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Ville Lindholm 2024-10-23 15:48:52 +03:00
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content/blog/psycopg2-nonblocking-1.md
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@ -24,7 +24,7 @@ The solution would be to have `psycopg2` spin up a new thread, run the PostgreSQ
Luckily, this very thing already exists! To make `psycopg2` stay in Python-land, just add the following in your app startup routines: Luckily, this very thing already exists! To make `psycopg2` stay in Python-land, just add the following in your app startup routines:
```python3 ```python
def init_psycopg2() -> None: def init_psycopg2() -> None:
import psycopg2.extensions import psycopg2.extensions
import psycopg2.extras import psycopg2.extras
@ -34,9 +34,9 @@ def init_psycopg2() -> None:
The `psycopg2.extras.wait_select` is just a reference implementation which will replicate the behavior of the default, blocking driver without getting stuck in C-land, and as an added bonus it automatically cancels the SQL query on a `KeyboardInterrupt`. It is of course possible to write your own function to pass into `set_wait_callback()`, which we did when we wrote some more advanced Celery features. The `psycopg2.extras.wait_select` is just a reference implementation which will replicate the behavior of the default, blocking driver without getting stuck in C-land, and as an added bonus it automatically cancels the SQL query on a `KeyboardInterrupt`. It is of course possible to write your own function to pass into `set_wait_callback()`, which we did when we wrote some more advanced Celery features.
A good starting point to learn about `set_wait_callback` is [https://www.psycopg.org/articles/2014/07/20/cancelling-postgresql-statements-python/](this short article). A good starting point to learn about `set_wait_callback` is [this short article](https://www.psycopg.org/articles/2014/07/20/cancelling-postgresql-statements-python/).
The fundamental reason why this feature exists in `psycopg2` is to [https://www.psycopg.org/docs/advanced.html#support-for-coroutine-libraries](enable running it in various coroutine / green thread implementations) in Python. We do not use green threads, we run a vanilla setup of Python which is fully synchronous. It is still extremely useful! The fundamental reason why this feature exists in `psycopg2` is to [enable running it in various coroutine / green thread implementations](https://www.psycopg.org/docs/advanced.html#support-for-coroutine-libraries) in Python. We do not use green threads, we run a vanilla setup of Python which is fully synchronous. It is still extremely useful!
## The result ## The result

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hugo.yaml
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@ -3,3 +3,7 @@ languageCode: en-us
title: Lindholm Software title: Lindholm Software
copyright: © Ville Lindholm copyright: © Ville Lindholm
disableHugoGeneratorInject: true disableHugoGeneratorInject: true
markup:
highlight:
style: solarized-dark