API key management in Prompt Engineering / GenAI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an API key?

An API key is a unique code passed by a client to an API to identify and authenticate the client making the request.

beginner

Why should API keys be kept secret?

API keys grant access to services and data. If exposed, unauthorized users can misuse the API, causing security risks and extra costs.

intermediate

What is the purpose of rotating API keys?

Rotating API keys means regularly changing them to reduce the risk of misuse if a key is compromised.

intermediate

How can you restrict API key usage?

You can restrict API keys by limiting IP addresses, setting usage quotas, or defining allowed API endpoints to improve security.

advanced

What is the difference between API key and OAuth token?

An API key is a simple static token for identification, while an OAuth token is a dynamic token that provides delegated access with user permissions.

What is the main role of an API key?

A Encrypt data between client and server

B Store user passwords

C Identify and authenticate the client

D Generate machine learning models

API keys are used to identify and authenticate clients making API requests.

Which practice helps protect API keys from misuse?

A Rotating keys regularly

B Sharing keys publicly

C Using the same key forever

D Ignoring usage limits

Regularly rotating API keys reduces the risk if a key is compromised.

How can API key usage be restricted?

A By using more keys

B By increasing key length

C By disabling encryption

D By limiting IP addresses

Restricting API keys by IP addresses limits where the key can be used.

What happens if an API key is exposed publicly?

A Unauthorized users can misuse the API

B The API key becomes stronger

C The API key automatically changes

D Nothing happens

Exposed API keys can be used by unauthorized users, causing security risks.

Which is a key difference between API keys and OAuth tokens?

A API keys expire every minute; OAuth tokens never expire

B API keys are static; OAuth tokens are dynamic

C OAuth tokens are used only for databases

D API keys require user passwords

API keys are static tokens, while OAuth tokens are dynamic and provide delegated access.

Explain why managing API keys carefully is important for security.

Think about what happens if someone else gets your key.

Describe methods to restrict API key usage to improve security.

Consider how to limit where and how keys are used.

Practice

1. What is the main purpose of an API key in AI services?

easy

A. To improve AI model accuracy

B. To speed up the AI model training

C. To store user data securely

D. To control who can access the AI service

Solution

1. Step 1: Understand API key role

   An API key acts like a password to allow access to AI services.

2. Step 2: Identify main purpose

   It controls who can use the service by authenticating requests.

3. Final Answer:

   To control who can access the AI service -> Option D

4. Quick Check:

   API key = Access control [OK]

Hint: API keys are like secret passwords for access [OK]

Common Mistakes:

• Thinking API keys improve model accuracy
• Confusing API keys with data storage
• Believing API keys speed up training

2. Which of the following is the correct way to include an API key in a request header?

easy

A. Authorization: Bearer YOUR_API_KEY

B. API-Key: YOUR_API_KEY

C. Key: YOUR_API_KEY

D. Token: YOUR_API_KEY

Solution

1. Step 1: Recall standard header format

   The common standard is to use 'Authorization' with 'Bearer' followed by the API key.

2. Step 2: Match correct header syntax

   Authorization: Bearer YOUR_API_KEY matches this standard format exactly.

3. Final Answer:

   Authorization: Bearer YOUR_API_KEY -> Option A

4. Quick Check:

   Authorization header uses Bearer token [OK]

Hint: Use 'Authorization: Bearer' for API keys in headers [OK]

Common Mistakes:

• Using incorrect header names like 'Key' or 'Token'
• Omitting 'Bearer' keyword
• Placing API key in URL instead of header

3. Consider this Python code snippet using an API key:

import requests
headers = {"Authorization": "Bearer abc123"}
response = requests.get("https://api.example.com/data", headers=headers)
print(response.status_code)

What will this code print if the API key is valid and the request succeeds?

medium

A. 401

B. 200

C. 404

D. 500

Solution

1. Step 1: Understand HTTP status codes

   200 means success, 401 means unauthorized, 404 means not found, 500 means server error.

2. Step 2: Analyze code behavior with valid key

   With a valid API key, the request should succeed and return status code 200.

3. Final Answer:

   200 -> Option B

4. Quick Check:

   Valid key + successful request = 200 [OK]

Hint: 200 means success, 401 means unauthorized [OK]

Common Mistakes:

• Confusing 401 unauthorized with success
• Assuming 404 means invalid key
• Thinking 500 is related to API key

4. You have this code snippet to send a request with an API key:

headers = {"Authorization": "Bearer " + api_key}
response = requests.get(url, headers=headers)

But you get a 401 Unauthorized error. What is the most likely cause?

medium

A. The requests library is not imported

B. The URL is misspelled

C. The API key variable is empty or incorrect

D. The server is down

Solution

1. Step 1: Understand 401 error meaning

   401 Unauthorized means the server rejected the request due to bad or missing credentials.

2. Step 2: Identify cause related to API key

   If the API key variable is empty or wrong, the Authorization header is invalid, causing 401.

3. Final Answer:

   The API key variable is empty or incorrect -> Option C

4. Quick Check:

   401 error = invalid credentials [OK]

Hint: 401 means check your API key value first [OK]

Common Mistakes:

• Blaming URL spelling for 401 error
• Ignoring missing import errors
• Assuming server down causes 401

5. You want to improve security by rotating your API keys regularly. Which approach is best to avoid service interruption?

hard

A. Create a new key, update your app to use it, then delete the old key

B. Delete the old key first, then create a new key

C. Use the same key forever without changes

D. Share your API key publicly to get feedback

Solution

1. Step 1: Understand key rotation process

   To avoid downtime, keep old key active until new key is working.

2. Step 2: Choose safe rotation order

   Create new key, update app, confirm it works, then delete old key.

3. Final Answer:

   Create a new key, update your app to use it, then delete the old key -> Option A

4. Quick Check:

   Rotate keys safely by overlapping usage [OK]

Hint: Add new key before deleting old one [OK]

Common Mistakes:

• Deleting old key before new key is ready
• Never rotating keys at all
• Sharing keys publicly