Redis as message broker in Django - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Redis client in Django.

Django

from redis import [1]

Drag options to blanks, or click blank then click option'

ARedis

BClient

CConnection

DBroker

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Client' instead of 'Redis' causes import errors.

Trying to import 'Broker' which does not exist in redis package.

The Redis client class is named Redis. Importing it allows you to connect to the Redis server.

2fill in blank

medium

Complete the code to publish a message to a Redis channel.

Django

redis_client = Redis()
redis_client.[1]('channel1', 'Hello World')

Drag options to blanks, or click blank then click option'

Abroadcast

Bpush

Csend

Dpublish

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'send' or 'push' which are not Redis client methods.

Trying to use 'broadcast' which is not a Redis method.

The method to send a message to a Redis channel is publish. It takes the channel name and the message.

3fill in blank

hard

Fix the error in subscribing to a Redis channel.

Django

pubsub = redis_client.[1]()
pubsub.subscribe('channel1')

Drag options to blanks, or click blank then click option'

Apubsub()

Bsubscribe

Cpubsub

Dpubsub_subscribe

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to call 'subscribe()' directly on the Redis client.

Using 'subscribe' as a method to create pubsub object.

To subscribe, you first create a pubsub object by calling pubsub() on the Redis client. Then you call subscribe() on that object.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps channel names to message counts, filtering only channels with more than 5 messages.

Django

message_counts = {channel: count for channel, count in redis_client.[1]('channel_counts').items() if count [2] 5}

Drag options to blanks, or click blank then click option'

Ahgetall

B>

C<

Dkeys

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'keys()' which returns only keys, not counts.

Using '<' which filters counts less than 5.

hgetall('channel_counts') retrieves all fields and values from a Redis hash. The comprehension filters counts greater than 5 using the '>' operator.

5fill in blank

hard

Fill all three blanks to create a Redis message handler that listens to a channel, decodes messages, and prints them.

Django

pubsub = redis_client.[1]()
pubsub.subscribe('[2]')
for message in pubsub.listen():
    if message['type'] == 'message':
        print(message['data'].[3]('utf-8'))

Drag options to blanks, or click blank then click option'

Apubsub

Bchannel1

Cdecode

Dsubscribe

Attempts:

3 left

💡 Hint

Common Mistakes

Calling 'subscribe' instead of 'pubsub()' to create the pubsub object.

Not decoding the message data before printing.

First, create a pubsub object with pubsub(). Then subscribe to the channel named channel1. Finally, decode the message data from bytes to string using decode('utf-8').