Service discovery concept in Microservices - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to register a service instance with the discovery server.

Microservices

discovery_client.register_service('[1]', '10.0.0.1', 8080)

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

Aservice_id

Bservice_name

Cservice_port

Dservice_address

Attempts:

3 left

💡 Hint

Common Mistakes

Using IP address or port as the service identifier.

Confusing service ID with service name.

The first argument should be the service name to identify the service in the discovery system.

2fill in blank

medium

Complete the code to discover the address of a service instance.

Microservices

address = discovery_client.get_service_address('[1]')

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Ainstance_id

Bservice_port

Cservice_name

Dnode_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using instance ID instead of service name.

Using port number or node ID which are not keys for discovery.

You need to provide the service name to get the address of one of its instances.

3fill in blank

hard

Fix the error in the service registration code to include health check.

Microservices

discovery_client.register_service('payment-service', '10.0.0.5', 9090, health_check='[1]')

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Ahttp://10.0.0.5:9090/health

B10.0.0.5:9090

C/health

Dhealth

Attempts:

3 left

💡 Hint

Common Mistakes

Providing only a path or IP without protocol.

Using a keyword instead of a URL.

The health check URL must be a full HTTP URL so the discovery server can call it to check service health.

4fill in blank

hard

Fill both blanks to create a dictionary of service instances filtered by status.

Microservices

healthy_services = {id: info for id, info in services.items() if info['[1]'] == '[2]'}

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Astatus

Bhealthy

Caddress

Dactive

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'address' as a key for filtering.

Using 'active' instead of 'healthy' as status value.

We filter services where the status key equals healthy to get only healthy instances.

5fill in blank

hard

Fill all three blanks to implement a simple client-side load balancer picking a random healthy instance.

Microservices

import random

instances = discovery_client.get_service_instances('[1]')
healthy = [i for i in instances if i['[2]'] == '[3]']
selected = random.choice(healthy)

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

Aorder-service

Bstatus

Chealthy

Daddress

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong service name.

Filtering by wrong key or value.

Not filtering before choosing randomly.

We get instances of 'order-service', filter by 'status' equal to 'healthy', then pick one randomly.