Circuit breaker pattern in HLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define the state when the circuit breaker allows requests.

HLD

state = "[1]"  # State when requests are allowed

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

AHalf-Open

BOpen

CClosed

DDisabled

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'Open' which actually blocks requests.

Confusing 'Half-Open' with the normal state.

The Closed state means the circuit breaker allows requests to pass through normally.

2fill in blank

medium

Complete the code to specify the state when the circuit breaker blocks requests.

HLD

if failure_count > threshold:
    state = "[1]"  # Block requests

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

AOpen

BClosed

CHalf-Open

DDisabled

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'Closed' which allows requests.

Confusing 'Half-Open' with the blocking state.

The Open state means the circuit breaker blocks requests to prevent further failures.

3fill in blank

hard

Fix the error in the code to transition the circuit breaker to the state that tests if the system has recovered.

HLD

if timeout_expired:
    state = "[1]"  # Test system recovery

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

ADisabled

BClosed

COpen

DHalf-Open

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Open' which keeps blocking requests.

Using 'Closed' which allows all requests without testing.

The Half-Open state allows a limited number of requests to test if the system has recovered.

4fill in blank

hard

Fill both blanks to complete the request handling logic in the circuit breaker.

HLD

if state == "[1]":
    allow_request = True
elif state == "[2]":
    allow_request = False

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

AClosed

BOpen

CHalf-Open

DDisabled

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the states and their meanings.

Using 'Disabled' which is not part of normal flow.

Requests are allowed in Closed state and blocked in Open state.

5fill in blank

hard

Fill all three blanks to complete the dictionary representing circuit breaker states and their descriptions.

HLD

states = {
    "Closed": "[1]",
    "Open": "[2]",
    "Half-Open": "[3]"
}

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

ARequests allowed

BRequests blocked

CTest limited requests

DSystem disabled

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing descriptions between states.

Including 'System disabled' which is not a standard state.

The Closed state means requests are allowed, Open means requests are blocked, and Half-Open means testing limited requests.