Service accounts for applications in GCP - Step-by-Step Execution

Process Flow - Service accounts for applications

Create Service Account

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Assign Roles/Permissions

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Application Uses Service Account

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Service Account Authenticates

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Access GCP Resources

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Perform Allowed Actions

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End

This flow shows how a service account is created, given permissions, then used by an application to access GCP resources securely.

Execution Sample

GCP

gcloud iam service-accounts create app-sa --display-name="App Service Account"
gcloud projects add-iam-policy-binding my-project --member="serviceAccount:[e-mail]" --role="roles/storage.objectViewer"
# Application uses app-sa key to authenticate and access storage

Create a service account, assign it a role to view storage objects, then the application uses it to access storage.

Process Table

Step	Action	Resource Affected	Result	Notes
1	Create service account 'app-sa'	IAM Service Accounts	Service account 'app-sa' created	Ready for permission assignment
2	Assign 'storage.objectViewer' role to 'app-sa'	IAM Policy Binding	Role assigned to 'app-sa'	Allows read access to storage objects
3	Application authenticates using 'app-sa' credentials	Authentication	Authentication successful	App can now act as 'app-sa'
4	Application requests storage object list	Cloud Storage	Access granted, object list returned	Permission check passed
5	Application tries to delete storage object	Cloud Storage	Access denied	No delete permission assigned
6	End	-	Execution stops	Application limited by assigned roles

💡 Execution stops because application only has read permission, no further actions allowed.

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	Final
Service Account 'app-sa'	Not created	Created	Created with role	Authenticated	Authenticated	Authenticated	Authenticated
Permissions	None	None	storage.objectViewer	storage.objectViewer	storage.objectViewer	storage.objectViewer	storage.objectViewer
Application Access	None	None	None	Allowed to read storage	Allowed to read storage	Denied delete storage	Denied delete storage

Key Moments - 2 Insights

Why can't the application delete storage objects even though it uses the service account?

Because the service account was only given the 'storage.objectViewer' role, which allows read-only access. This is shown in execution_table step 5 where delete is denied.

What happens if the service account is not assigned any role?

The application cannot access any resources because the service account has no permissions. This is implied before step 2 in the execution_table.

Visual Quiz - 3 Questions

Look at the execution table, at which step does the application successfully authenticate using the service account?

A Step 2

B Step 3

C Step 4

D Step 5

💡 Hint

Check the 'Result' column for authentication success in the execution_table.

According to the variable tracker, what permission does the service account have after step 2?

A storage.admin

B No permissions

C storage.objectViewer

D storage.objectCreator

💡 Hint

Look at the 'Permissions' row after step 2 in the variable_tracker.

If the application needed to delete storage objects, what change would you make in the execution table?

A Assign 'storage.objectAdmin' role to the service account

B Remove the service account

C Change authentication method

D No change needed

💡 Hint

Refer to step 5 where delete is denied due to insufficient permissions.

Concept Snapshot

Service accounts are special accounts for applications to access GCP resources.
Create a service account, assign roles to grant permissions.
Applications authenticate using service account credentials.
Permissions control what actions the app can perform.
Least privilege: assign only needed roles for security.

Full Transcript

Service accounts let applications securely access Google Cloud resources. First, create a service account. Then assign it roles that define what it can do, like reading storage objects. The application uses the service account's credentials to authenticate. Once authenticated, the app can perform actions allowed by the assigned roles. For example, if the service account has only read permissions, the app cannot delete storage objects. This keeps access secure and limited to what is necessary.