Members (users, groups, service accounts) in GCP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

Identify the member type from the IAM policy binding

Given the following IAM policy binding member string, what type of member does it represent?

serviceAccount:[e-mail]

A A Google group

B A user account

C A service account

D A Google Workspace domain

💡 Hint

Look at the prefix before the colon in the member string.

The prefix 'serviceAccount:' indicates the member is a service account, which is a special account used by applications or virtual machines to interact with Google Cloud services.

🧠 Conceptual

intermediate

Understanding group members in IAM policies

Which of the following member strings correctly represents a Google group in an IAM policy binding?

A user:[e-mail]

B domain:example.com

C serviceAccount:[e-mail]

D group:[e-mail]

💡 Hint

Groups have a specific prefix in the member string.

The prefix 'group:' identifies the member as a Google group, which can contain multiple users and service accounts.

❓ security

advanced

Least privilege principle with service accounts

You want to grant a Compute Engine VM the ability to read from a Cloud Storage bucket. Which member should you add to the bucket's IAM policy to follow the least privilege principle?

A serviceAccount:[e-mail]

B user:[e-mail]

C group:[e-mail]

D domain:example.com

💡 Hint

Grant permissions only to the entity that needs access, not to broad groups or domains.

Granting the service account associated with the VM limits access to only that VM, following the least privilege principle.

❓ Architecture

advanced

Choosing the right member type for automated workflows

You have an automated workflow running on Cloud Functions that needs to access BigQuery data. Which member type should you assign permissions to for best practice?

A serviceAccount:[e-mail]

B user:[e-mail]

C group:[e-mail]

D domain:example.com

💡 Hint

Automated workflows should use identities that represent the service, not individual users or broad groups.

Using a service account for Cloud Functions allows fine-grained control and better security for automated workflows.

✅ Best Practice

expert

Managing access with Google Workspace domains in IAM

You want to grant read access to all users in your company’s Google Workspace domain to a Cloud Storage bucket. Which member string should you use in the IAM policy binding?

A user:[e-mail]

B domain:example.com

C group:[e-mail]

D serviceAccount:[e-mail]

💡 Hint

Think about how to grant access to everyone in a domain without listing individual users or groups.

Using 'domain:example.com' grants access to all users in that Google Workspace domain, which is efficient for company-wide permissions.

Practice

1. Which of the following is a correct way to specify a user as a member in GCP IAM?

easy

A. user:[e-mail]

B. serviceaccount:[e-mail]

C. group:[e-mail]

D. member:[e-mail]

Solution

1. Step 1: Understand member types in GCP IAM

   GCP IAM requires a prefix to identify the member type, such as user, group, or serviceaccount.

2. Step 2: Identify the correct prefix for a user

   The prefix for an individual user is user:. So the correct format is user:email.

3. Final Answer:

   user:[e-mail] -> Option A

4. Quick Check:

   User members start with 'user:' [OK]

Hint: User members always start with 'user:' prefix [OK]

Common Mistakes:

• Using 'member:' prefix which is invalid
• Confusing group and user prefixes
• Using serviceaccount prefix for users

2. Which of the following is the correct syntax to specify a service account member in GCP IAM?

easy

A. service-account:[e-mail]

B. serviceaccount:[e-mail]

C. group:[e-mail]

D. user:[e-mail]

Solution

1. Step 1: Recall the prefix for service accounts

   Service accounts use the prefix serviceaccount: followed by the full service account email.

2. Step 2: Check each option's prefix

   Only serviceaccount:[e-mail] uses the correct prefix serviceaccount: without hyphens or mistakes.

3. Final Answer:

   serviceaccount:[e-mail] -> Option B

4. Quick Check:

   Service accounts use 'serviceaccount:' prefix [OK]

Hint: Service accounts use 'serviceaccount:' prefix without hyphens [OK]

Common Mistakes:

• Using 'service-account:' with a hyphen
• Using 'user:' prefix for service accounts
• Using incomplete email addresses

3. Given the following IAM policy binding snippet, which member will have access?

{"role": "roles/viewer", "members": ["group:[e-mail]", "user:[e-mail]"]}

medium

A. Only users in the dev-team group and Bob

B. Only Bob

C. Only the dev-team group

D. All users in the project

Solution

1. Step 1: Analyze the members list in the policy

   The members list includes group:[e-mail] and user:[e-mail]. Both are granted the role.

2. Step 2: Understand access granted by group and user members

   All users in the dev-team group plus the individual user Bob have the role permissions.

3. Final Answer:

   Only users in the dev-team group and Bob -> Option A

4. Quick Check:

   Group and user members both get access [OK]

Hint: Group members grant access to all group users [OK]

Common Mistakes:

• Assuming only one member gets access
• Confusing group with user access scope
• Thinking all project users get access

4. You tried to add a member with user:alice to an IAM policy but got an error. What is the likely cause?

medium

A. IAM policy does not support user members

B. Using 'user:' prefix instead of 'group:'

C. Service account email used instead of user email

D. Missing full email address after 'user:' prefix

Solution

1. Step 1: Check the required format for user members

   User members must include the full email address after the user: prefix.

2. Step 2: Identify the error cause

   Using just user:alice is incomplete and causes a format error.

3. Final Answer:

   Missing full email address after 'user:' prefix -> Option D

4. Quick Check:

   User members need full email [OK]

Hint: Always include full email after 'user:' [OK]

Common Mistakes:

• Using only username without domain
• Confusing user and group prefixes
• Assuming IAM rejects user members

5. You want to grant a Cloud Function access to a Pub/Sub topic using a service account. Which member string should you add to the Pub/Sub IAM policy?

hard

A. group:[e-mail]

B. user:[e-mail]

C. serviceaccount:[e-mail]

D. service-account:[e-mail]

Solution

1. Step 1: Identify the correct member type for Cloud Function access

   Cloud Functions use service accounts to access other resources, so the member must be a service account.

2. Step 2: Use the correct prefix for service accounts

   The prefix is serviceaccount: followed by the full service account email.

3. Step 3: Verify the options

   Only serviceaccount:[e-mail] uses the correct prefix and format.

4. Final Answer:

   serviceaccount:[e-mail] -> Option C

5. Quick Check:

   Service accounts use 'serviceaccount:' prefix [OK]

Hint: Use 'serviceaccount:' prefix for Cloud Function identities [OK]

Common Mistakes:

• Using 'user:' prefix for service accounts
• Adding group instead of service account
• Using incorrect prefix with hyphen