Redis as message broker in Flask - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Redis client in a Flask app.

Flask

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 'Connection' which is not the main client class.

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

2fill in blank

medium

Complete the code to create a Redis client instance connecting to localhost.

Flask

redis_client = Redis(host=[1], port=6379, db=0)

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

A'remotehost'

B'localhost'

C'127.0.0.2'

D'0.0.0.0'

Attempts:

3 left

💡 Hint

Common Mistakes

Using IP addresses other than 127.0.0.1 for local connection.

Using '0.0.0.0' which means all interfaces, not a specific host.

To connect to the local Redis server, use 'localhost' as the host.

3fill in blank

hard

Fix the error in publishing a message to a Redis channel.

Flask

redis_client.[1]('notifications', 'Hello World!')

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

Apost

Bsend

Cpublish

Dpush

Attempts:

3 left

💡 Hint

Common Mistakes

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

Using 'post' which is unrelated to Redis messaging.

The correct method to send a message to a Redis channel is publish.

4fill in blank

hard

Fill both blanks to subscribe to a Redis channel and listen for messages.

Flask

pubsub = redis_client.[1]()
pubsub.[2]('updates')

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Apubsub

Bsubscribe

Clisten

Dsubscribe_channel

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'listen' instead of 'subscribe' to subscribe to a channel.

Trying to call 'subscribe_channel' which does not exist.

First, create a pubsub object with pubsub(), then subscribe to a channel with subscribe().

5fill in blank

hard

Fill all three blanks to receive and print messages from a Redis subscription.

Flask

for message in pubsub.[1]():
    if message['[2]'] == 'message':
        print(message['[3]'])

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

Alisten

Btype

Cdata

Dsubscribe

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'subscribe' instead of 'listen' to receive messages.

Checking wrong keys in the message dictionary.

Use listen() to get messages, check if type == 'message' (message type), then print the data content.