CI/CD tools landscape in Jenkins - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a Jenkins pipeline stage named 'Build'.

Jenkins

stage('[1]') {
    steps {
        echo 'Building the project'
    }
}

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

ABuild

BTest

CDeploy

DClean

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong stage name like 'Test' when the step is building.

Leaving the stage name empty.

The stage name should be 'Build' to represent the build step in the pipeline.

2fill in blank

medium

Complete the code to trigger the pipeline only when changes are pushed to the 'main' branch.

Jenkins

pipeline {
    agent any
    triggers {
        [1] {
            pollSCM('H/5 * * * *')
        }
    }
    stages {
        stage('Build') {
            steps {
                echo 'Building...'
            }
        }
    }
}

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

ApollSCM

Bbranch

Ccron

DgithubPush

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'cron' which triggers on a schedule, not on code changes.

Using 'branch' which is not a valid trigger keyword.

The 'pollSCM' trigger checks the source code management for changes, and can be configured to watch the 'main' branch.

3fill in blank

hard

Fix the error in the Jenkinsfile snippet to correctly checkout code from Git.

Jenkins

pipeline {
    agent any
    stages {
        stage('Checkout') {
            steps {
                [1]([$class: 'GitSCM', branches: [[name: '*/main']], userRemoteConfigs: [[url: 'https://github.com/example/repo.git']]])
            }
        }
    }
}

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

Aclone

Bcheckout

CgitClone

DgitCheckout

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'gitCheckout' which is not a valid Jenkins step.

Using 'clone' which is a git command but not a Jenkins pipeline step.

The correct Jenkins pipeline step to checkout code is 'checkout'.

4fill in blank

hard

Fill both blanks to create a post-build action that always sends an email notification.

Jenkins

post {
    [1] {
        mail to: '[e-mail]', subject: 'Build [2]', body: 'The build has finished.'
    }
}

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

Aalways

Bsuccess

Cfailure

Dunstable

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'success' which only runs on successful builds.

Using 'failure' which only runs on failed builds.

The 'always' block runs after every build, and the subject uses 'always' to indicate the build status.

5fill in blank

hard

Fill all three blanks to define an environment variable and use it in a shell step.

Jenkins

pipeline {
    agent any
    environment {
        [1] = '[2]'
    }
    stages {
        stage('Print Env') {
            steps {
                sh 'echo [3]'
            }
        }
    }
}

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

AMY_VAR

BHelloWorld

C$MY_VAR

DGREETING

Attempts:

3 left

💡 Hint

Common Mistakes

Using variable name with lowercase letters.

Not using '$' to reference the variable in shell.

Define environment variable 'MY_VAR' with value 'HelloWorld' and use it in shell with '$MY_VAR'.

Practice

1. What is the main purpose of CI/CD tools like Jenkins in software development?

easy

A. To design user interfaces

B. To write code manually

C. To automate building, testing, and deploying software

D. To manage hardware resources

Solution

1. Step 1: Understand CI/CD tools role

   CI/CD tools automate repetitive tasks in software development like building, testing, and deploying.

2. Step 2: Compare options

   Options B, C, and D describe unrelated tasks. Only To automate building, testing, and deploying software matches the automation purpose.

3. Final Answer:

   To automate building, testing, and deploying software -> Option C

4. Quick Check:

   CI/CD tools automate software delivery = A [OK]

Hint: CI/CD tools automate software delivery steps [OK]

Common Mistakes:

• Confusing CI/CD tools with coding or design tools
• Thinking CI/CD tools manage hardware
• Assuming CI/CD tools replace developers

2. Which of the following is the correct way to define a stage in a Jenkins pipeline?

easy

A. stage('Build') { steps { echo 'Building...' } }

B. step('Build') { echo 'Building...' }

C. stage: Build { echo 'Building...' }

D. buildStage { echo 'Building...' }

Solution

1. Step 1: Recall Jenkins pipeline syntax

   Jenkins uses stage('name') { steps { ... } } to define stages.

2. Step 2: Check options for correct syntax

   Only stage('Build') { steps { echo 'Building...' } } matches the correct syntax with stage and steps blocks.

3. Final Answer:

   <code>stage('Build') { steps { echo 'Building...' } }</code> -> Option A

4. Quick Check:

   Correct Jenkins stage syntax = C [OK]

Hint: Stages use stage('name') with steps block [OK]

Common Mistakes:

• Using 'step' instead of 'stage'
• Missing the steps block inside stage
• Incorrect block syntax with colons or missing braces

3. Given this Jenkins pipeline snippet, what will be printed during the 'Test' stage?

pipeline {
  agent any
  stages {
    stage('Build') {
      steps { echo 'Building...' }
    }
    stage('Test') {
      steps { echo 'Testing...' }
    }
  }
}

medium

A. Testing... Building...

B. Testing...

C. Building...

D. Building... Testing...

Solution

1. Step 1: Understand pipeline stage order

   The pipeline runs stages in order: 'Build' then 'Test'.

2. Step 2: Identify echo outputs

   'Build' stage prints 'Building...', 'Test' stage prints 'Testing...'. Both run sequentially.

3. Final Answer:

   Building... Testing... -> Option D

4. Quick Check:

   Stages run in order, print messages in sequence = B [OK]

Hint: Stages run sequentially, outputs print in order [OK]

Common Mistakes:

• Assuming stages run in parallel by default
• Mixing output order
• Ignoring all stages run unless skipped

4. Identify the error in this Jenkins pipeline snippet:

pipeline {
  agent any
  stages {
    stage('Deploy') {
      step { echo 'Deploying...' }
    }
  }
}

medium

A. The keyword should be 'steps' not 'step'

B. Missing agent declaration

C. Stage name must be lowercase

D. Echo command is invalid

Solution

1. Step 1: Check pipeline syntax for stages

   Inside a stage, the correct block is steps (plural), not step.

2. Step 2: Verify other parts

   Agent is declared, stage name case is allowed, echo is valid. Only 'step' is wrong.

3. Final Answer:

   The keyword should be 'steps' not 'step' -> Option A

4. Quick Check:

   Use 'steps' block inside stage = A [OK]

Hint: Inside stage use 'steps' plural block [OK]

Common Mistakes:

• Using 'step' instead of 'steps'
• Thinking stage names must be lowercase
• Assuming echo is not allowed

5. You want to create a Jenkins pipeline that builds, tests, and deploys only if tests pass. Which approach best fits this CI/CD workflow?

hard

A. Skip Test stage and deploy immediately after Build

B. Define sequential stages: Build, Test, Deploy; Deploy runs only if Test succeeds

C. Deploy first, then Build and Test in any order

D. Run Build and Deploy stages in parallel, then Test last

Solution

1. Step 1: Understand CI/CD workflow logic

   Tests must pass before deploying to avoid broken releases.

2. Step 2: Choose pipeline structure

   Sequential stages Build -> Test -> Deploy ensure deploy runs only if tests succeed.

3. Step 3: Evaluate other options

   Parallel or skipping tests risks deploying broken code; deploying first is illogical.

4. Final Answer:

   Define sequential stages: Build, Test, Deploy; Deploy runs only if Test succeeds -> Option B

5. Quick Check:

   Sequential stages with test gate = D [OK]

Hint: Deploy only after successful tests in sequence [OK]

Common Mistakes:

• Running deploy before tests
• Skipping tests to save time
• Running build and deploy in parallel