Django comes with a robust cache system that lets you save dynamic pages, so they don’t have to be calculated for each request. The Django caching system can make use of varying cache mechanisms and includes a framework for adding new ones.
To use the Django cache API, the first step is to set your CACHE setting in your settings.py file. Here, the Django documentation gives an example of a simple local-memory caching setup:
```
CACHE = {
‘default’: {
‘BACKEND’: ‘django.core.cache.backends.locmem.LocMemCache’,
‘LOCATION’: ‘unique-snowflake’,
}
}
```
Second, the cache\_page can be used as a decorator to any view function. With this, Django will cache the output of the view function for the given duration. For instance, if you want to cache a view for 15 minutes, this can be done like so:
```
from django.views.decorators.cache import cache_page
@cache_page(60 * 15)
def my_view(request):
…
```
When the cache\_page decorator is used, the output is only generated once every 15 minutes, regardless of how many users access it.
In addition to this, Django’s cache framework includes tools for cache invalidation, which can be used, with key-based invalidation, to clear the cache.
The cache’s low-level cache API is also valuable for caching data in your views by setting and getting keys. Here is an example from the Django documentation.
```
from django.core.cache import cache
def my_view(request): my_data = cache.get(‘my_data’) if my_data is None: result = generate_expensive_data() cache.set(‘my_data’, result, 60 * 15) my_data = result
return my_data ```In the example above, “my_data” is being fetched from the cache. If it isn’t in the cache, the generate_expensive\_data() function will get executed, and its result will be stored in the cache for 15 minutes.
Remember that you can use several other settings to alter the behavior of your cache, such as TIMEOUT, which changes the default timeout period, and OPTIONS that specify cache-backend-specific options.
To conclude, Django cache API provides a flexible and user-friendly way for both page and data-level caching in Django applications. The API itself provides a plethora of usage options, which can cater to varying needs of differing applications. And by using this, Django developers can efficiently improve the performance of their applications.
The information provided was sourced from the official Django documentation, which is an excellent resource for anyone seeking to understand more about the Django cache API (source: https://docs.djangoproject.com/en/3.2/topics/cache/).
