Cache framework configuration in Django - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What is the output of this Django cache configuration?

Given the following Django cache settings, what will be the cache timeout for the default cache?

Django

CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
        'LOCATION': 'unique-snowflake',
        'TIMEOUT': 300,
    }
}

cache_timeout = CACHES['default']['TIMEOUT']

A 300

B None

C 0

D 60

💡 Hint

Look at the TIMEOUT value set in the default cache dictionary.

The TIMEOUT key in the cache configuration sets the cache expiration time in seconds. Here it is set to 300 seconds.

📝 Syntax

intermediate

Which cache backend setting is syntactically correct?

Identify the correct Django cache backend setting syntax.

A 'BACKEND': 'django.core.cache.backends.memcached.MemcacheCache'

B 'BACKEND': 'django.core.cache.backends.memcached.Memcached'

C 'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache'

D 'BACKEND': 'django.core.cache.backends.memcached.CacheMemcached'

💡 Hint

Check the official Django cache backend class names.

The correct backend class for Memcached in Django is 'MemcachedCache'. Other options are invalid class names.

🔧 Debug

advanced

Why does this cache configuration raise an error?

Examine the following cache configuration and identify the cause of the error.

Django

CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
        'LOCATION': 'unique-snowflake',
        'TIMEOUT': 300,
    }
}

A TIMEOUT cannot be set in cache configuration

B Invalid backend name causes ImportError

C LOCATION value must be an integer, not string

D Missing comma after 'LocMemCache' string causes SyntaxError

💡 Hint

Look carefully at the dictionary syntax between keys.

The missing comma after the 'BACKEND' value causes a syntax error in the dictionary definition.

❓ state_output

advanced

What is the value of cache key after this code runs?

Given this Django cache usage code, what will be the value of 'my_key' in the cache after execution?

Django

from django.core.cache import cache

cache.set('my_key', 'hello', timeout=10)
cache.set('my_key', 'world', timeout=None)
value = cache.get('my_key')

A 'world'

B 'hello'

C None

D Raises KeyError

💡 Hint

The second set call overwrites the first with no timeout.

The second cache.set call replaces the value with 'world' and sets timeout to None, meaning it never expires.

🧠 Conceptual

expert

Which cache configuration ensures thread-safe in-memory caching in Django?

Select the cache backend configuration that provides thread-safe in-memory caching suitable for development.

A {'BACKEND': 'django.core.cache.backends.memcached.PyMemcacheCache', 'LOCATION': '127.0.0.1:11211'}

B {'BACKEND': 'django.core.cache.backends.locmem.LocMemCache', 'LOCATION': 'unique-snowflake'}

C {'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache', 'LOCATION': '/var/tmp/django_cache'}

D {'BACKEND': 'django.core.cache.backends.dummy.DummyCache'}

💡 Hint

Consider which backend is designed for thread-safe local memory caching.

LocMemCache is thread-safe and stores cache in local memory, ideal for development and testing.