📝 Assessment – Context, Timeouts & Cancellation

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🎯 Objective

Evaluate your ability to:

• Understand and apply context.Context
• Handle timeouts and cancellations correctly
• Write clean, idiomatic Go code
• Think in production scenarios

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🧠 Section 1 – Conceptual Questions

Q1. What is the purpose of context.Context in Go?

Explain in your own words.

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Q2. Difference between:

• context.WithCancel
• context.WithTimeout
• context.WithDeadline

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Q3. Why should context be passed as the first parameter?

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Q4. What happens if you do not call cancel()?

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Q5. Why is storing context in a struct considered bad practice?

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Q6. When should you NOT use context?

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💻 Section 2 – Code Writing

Q7. Write a function:

func process(ctx context.Context) error

Requirements:

• Simulate work for 3 seconds
• Return early if context is cancelled
• Return appropriate error

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Q8. Create a program:

• Start a goroutine
• Use context.WithCancel
• Stop the goroutine after 2 seconds

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Q9. Implement timeout handling:

• Create a function that runs for 5 seconds
• Use a 2-second timeout
• Print whether it completed or timed out

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🐞 Section 3 – Debugging

Q10. Identify the issue:

func badWorker(ctx context.Context) {
	for {
		fmt.Println("Working...")
		time.Sleep(time.Second)
	}
}

👉 What is wrong? Fix it.

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Q11. Identify the issue:

ctx, _ := context.WithTimeout(context.Background(), 2*time.Second)

👉 What is missing? Why is it important?

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🧩 Section 4 – Scenario-Based

Q12. API Call Scenario

You are calling an external API that may:

• Take too long
• Fail intermittently

👉 How will you:

• Use context to control it?
• Avoid system slowdown?

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Q13. Microservice Chain

Service A → Service B → Database

👉 How should context flow across services?

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Q14. Goroutine Leak Scenario

You start multiple goroutines but forget to handle context.

👉 What problems can arise?

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⭐ Bonus Challenge

Q15. Design a retry mechanism:

• Retry every 1 second

• Stop if:

  • Context is cancelled
  • Operation succeeds

Explain your approach.

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📊 Evaluation Criteria

Area	What is Expected
Concepts	Clear understanding of context usage
Code Quality	Clean, idiomatic Go
Error Handling	Proper use of ctx.Err()
Concurrency	Safe and controlled
Thinking	Real-world awareness

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🚀 Completion Criteria

You are considered proficient in this chapter if you can:

• Correctly implement cancellation and timeouts
• Write context-aware functions
• Avoid common mistakes
• Explain concepts confidently

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💬 Discussion (To be reviewed with mentor)

• What was the most confusing part?
• Where do you see context being used in real projects?
• How is this different from Python?

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👉 Next: Weekly Questions

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