23 lines
866 B
ReStructuredText
23 lines
866 B
ReStructuredText
How django-cachalot works
|
||
-------------------------
|
||
|
||
.. note:: If you don’t understand, you can pretend it’s magic.
|
||
|
||
Reverse engineering
|
||
...................
|
||
|
||
It’s a lot of Django reverse engineering combined with a strong test suite.
|
||
Such a test suite is crucial for a reverse engineering project.
|
||
If some important part of Django changes and breaks the expected behaviour,
|
||
you can be sure that the test suite will fail.
|
||
|
||
Monkey patching
|
||
...............
|
||
|
||
Django-cachalot modifies Django in place during execution to add a caching tool
|
||
just before SQL queries are executed.
|
||
When a SQL query reads data, we save the result in cache. If that same query is
|
||
executed later, we fetch that result from cache.
|
||
When we detect ``INSERT``, ``UPDATE`` or ``DELETE``, we know which tables are
|
||
modified. All the previous cached queries can therefore be safely invalidated.
|