uWSGI Backend

class cachelib.uwsgi.UWSGICache(default_timeout=300, cache='', ignore_delete_many_errors=True)

Bases: BaseCache

Implements the cache using uWSGI’s caching framework.

Note

This class cannot be used when running under PyPy, because the uWSGI API implementation for PyPy is lacking the needed functionality.

Parameters:

  • default_timeout (int | timedelta) –

    The default timeout, either a number of seconds or a datetime.timedelta.

    Changed in version 0.17.0: Accepts a datetime.timedelta.

  • cache (str) – The name of the caching instance to connect to, for example: mycache@localhost:3031, defaults to an empty string, which means uWSGI will cache in the local instance. If the cache is in the same instance as your app, you only have to provide the name of the cache.

  • ignore_delete_many_errors (bool) –

    If False, delete_many() will raise a RuntimeError if any key fails to delete. Keys that do not exist are considered successfully deleted and do not raise.

    Changelog

    Added in version 0.16.0.

serializer = <cachelib.serializers.UWSGISerializer object>
get(key)

Look up key in the cache and return the value for it.

Parameters:

key (str) – the key to be looked up.

Returns:

The value if it exists and is readable, else None.

Return type:

Any

delete(key)

Delete key from the cache.

Parameters:

key (str) – the key to delete.

Returns:

Whether the key existed and has been deleted.

Return type:

bool

set(key, value, timeout=None)

Add a new key/value to the cache (overwrites value, if key already exists in the cache).

Parameters:

  • key (str) – the key to set

  • value (Any) – the value for the key

  • timeout (int | timedelta | None) – the cache timeout for the key, either a number of seconds or a datetime.timedelta (if not specified, it uses the default timeout). A timeout of 0 indicates that the cache never expires.

Returns:

True if key has been updated, False for backend errors. Pickling errors, however, will raise a subclass of pickle.PickleError.

Return type:

Literal[True] | None

add(key, value, timeout=None)

Works like set() but does not overwrite the values of already existing keys.

Parameters:

  • key (str) – the key to set

  • value (Any) – the value for the key

  • timeout (int | timedelta | None) – the cache timeout for the key, either a number of seconds or a datetime.timedelta (if not specified, it uses the default timeout). A timeout of 0 indicates that the cache never expires.

Returns:

Same as set(), but also False for already existing keys.

Return type:

bool

clear()

Clears the cache. Keep in mind that not all caches support completely clearing the cache.

Returns:

Whether the cache has been cleared.

Return type:

bool

has(key)

Checks if a key exists in the cache without returning it. This is a cheap operation that bypasses loading the actual data on the backend.

Parameters:

key (str) – the key to check

Return type:

bool