Script approval and sandbox in Jenkins - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to approve a script signature in Jenkins.

Jenkins

def approved = Jenkins.instance.getExtensionList('hudson.scm.SCM')[0].[1]('script-signature')

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

AgetDescriptorByName

BgetDescriptor

CgetScriptApproval

DgetSignature

Attempts:

3 left

💡 Hint

Common Mistakes

Using getDescriptor or getDescriptorByName instead of getScriptApproval.

Trying to get a signature directly without accessing script approval.

The getScriptApproval method accesses the script approval system in Jenkins.

2fill in blank

medium

Complete the code to check if a script is approved in Jenkins sandbox.

Jenkins

def isApproved = Jenkins.instance.getScriptApproval().[1]('signature')

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

AhasSignature

BisSignatureApproved

CisApproved

DcheckApproval

Attempts:

3 left

💡 Hint

Common Mistakes

Using isApproved which is not a method in this context.

Using hasSignature which only checks presence, not approval.

The method isSignatureApproved checks if a specific script signature is approved.

3fill in blank

hard

Fix the error in the code to add a script signature for approval.

Jenkins

Jenkins.instance.getScriptApproval().[1]('new-signature')

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

AaddSignature

BapproveSignature

CaddApprovedSignature

DaddScriptSignature

Attempts:

3 left

💡 Hint

Common Mistakes

Using approveSignature which is not a method.

Using addScriptSignature which does not exist.

The method addSignature adds a new script signature to the approval list.

4fill in blank

hard

Fill both blanks to create a script approval object and approve a signature.

Jenkins

def approval = Jenkins.instance.[1]()
approval.[2]('signature-to-approve')

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

AgetScriptApproval

BapproveSignature

CaddSignature

DgetApproval

Attempts:

3 left

💡 Hint

Common Mistakes

Using getApproval which does not exist.

Using addSignature instead of approveSignature for approval.

First, get the script approval object with getScriptApproval(), then approve the signature with approveSignature().

5fill in blank

hard

Fill all three blanks to reject a script signature and save the approval state.

Jenkins

def approval = Jenkins.instance.[1]()
approval.[2]('signature-to-reject')
approval.[3]()

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

AgetScriptApproval

BrejectSignature

Csave

DremoveSignature

Attempts:

3 left

💡 Hint

Common Mistakes

Using removeSignature which does not reject but removes.

Forgetting to call save() after changes.

Get the script approval object, reject the signature, then save the changes.

Practice

1. What is the main purpose of script approval in Jenkins?

easy

A. To automatically run all scripts without restrictions

B. To protect Jenkins by allowing admins to approve unsafe scripts before execution

C. To speed up the build process by skipping script checks

D. To disable all scripts in Jenkins

Solution

1. Step 1: Understand script approval role

   Script approval is designed to protect Jenkins by controlling which scripts can run.

2. Step 2: Identify admin involvement

   Admins review and approve scripts to prevent unsafe code from running.

3. Final Answer:

   To protect Jenkins by allowing admins to approve unsafe scripts before execution -> Option B

4. Quick Check:

   Script approval = Admin review for safety [OK]

Hint: Script approval means admin checks scripts before running [OK]

Common Mistakes:

• Thinking scripts run automatically without checks
• Confusing script approval with disabling scripts
• Assuming script approval speeds up builds

2. Which of the following is the correct way to enable sandbox mode in a Jenkins Pipeline script?

easy

A. Check the 'Use Groovy Sandbox' option in the Pipeline script configuration

B. Use @Sandbox annotation at the top of the script

C. Add sandbox=true inside the Jenkinsfile

D. Enable sandbox mode in Jenkins global settings only

Solution

1. Step 1: Identify sandbox enabling method

   Sandbox mode is enabled by checking the 'Use Groovy Sandbox' box in the Pipeline script configuration.

2. Step 2: Verify other options

   Annotations or code inside Jenkinsfile do not enable sandbox; global settings do not control this per script.

3. Final Answer:

   Check the 'Use Groovy Sandbox' option in the Pipeline script configuration -> Option A

4. Quick Check:

   Sandbox enabled via checkbox in script config [OK]

Hint: Sandbox mode is a checkbox in Pipeline script config [OK]

Common Mistakes:

• Trying to enable sandbox with code annotations
• Assuming sandbox is a global-only setting
• Adding sandbox flags inside Jenkinsfile

3. Given this Jenkins Pipeline snippet running with sandbox enabled:

node {
  def result = sh(script: 'echo Hello', returnStdout: true).trim()
  echo result
}

What will be the output?

medium

A. No output because sandbox blocks shell commands

B. Syntax error due to sandbox

C. result

D. Hello

Solution

1. Step 1: Analyze the sh step

   sh(script: 'echo Hello', returnStdout: true).trim() executes 'echo Hello', captures stdout, trims to 'Hello', assigns to result.

2. Step 2: Analyze echo step

   echo result prints the value of result ('Hello'). In Jenkins Pipeline, the echo step prints variable values directly. Sandbox allows whitelisted steps like sh and echo.

3. Final Answer:

   Hello -> Option D

4. Quick Check:

   sh captures stdout, echo prints var value [OK]

Hint: In Pipeline, echo result prints result's value [OK]

Common Mistakes:

• Thinking echo prints literal 'result' like shell
• Believing sandbox blocks whitelisted sh commands
• Expecting syntax error from sandbox

4. You wrote a Jenkins Pipeline script that uses a method not whitelisted in the sandbox. The build fails with a script approval error. What should you do to fix this?

medium

A. Restart Jenkins to clear the error

B. Remove sandbox mode and run the script without restrictions

C. Ask the Jenkins admin to approve the method in the script approval page

D. Rewrite the script to avoid using any methods

Solution

1. Step 1: Understand script approval error cause

   The error occurs because the method is not approved in Jenkins script approval.

2. Step 2: Fix by admin approval

   The correct fix is to have the Jenkins admin approve the method via the script approval UI.

3. Final Answer:

   Ask the Jenkins admin to approve the method in the script approval page -> Option C

4. Quick Check:

   Approval needed for unapproved methods [OK]

Hint: Unapproved methods need admin approval, not disabling sandbox [OK]

Common Mistakes:

• Disabling sandbox instead of approving scripts
• Trying to remove methods instead of approval
• Restarting Jenkins does not fix approval errors

5. You want to run a custom Groovy script in Jenkins Pipeline that uses a non-whitelisted method and also requires sandbox protection. Which approach correctly balances safety and functionality?

hard

A. Run the script with sandbox enabled and request admin approval for the method

B. Disable sandbox and run the script directly to avoid approval delays

C. Rewrite the script to avoid all non-whitelisted methods, ignoring sandbox

D. Run the script outside Jenkins and import results to avoid sandbox issues

Solution

1. Step 1: Understand sandbox and approval roles

   Sandbox protects Jenkins by restricting unsafe code; approval allows safe exceptions.

2. Step 2: Balance safety and functionality

   Enabling sandbox with admin approval keeps Jenkins safe while allowing needed methods.

3. Final Answer:

   Run the script with sandbox enabled and request admin approval for the method -> Option A

4. Quick Check:

   Sandbox + approval = safe and functional scripts [OK]

Hint: Use sandbox plus admin approval for safe custom scripts [OK]

Common Mistakes:

• Disabling sandbox risking Jenkins security
• Avoiding needed methods by rewriting scripts unnecessarily
• Running scripts outside Jenkins complicates workflow