Build pipeline basics in Azure - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Azure DevOps YAML Pipeline: Output of a simple build step

What will be the output of this Azure DevOps pipeline step when it runs successfully?

Azure

steps:
- script: echo Hello, Azure DevOps!
  displayName: 'Print greeting'

A Hello, Azure DevOps!

B Print greeting

C

steps:
- script: echo Hello, Azure DevOps!

D No output, only logs

💡 Hint

The script step runs a shell command and prints its output.

The script step runs the echo command, which outputs the text 'Hello, Azure DevOps!' to the console.

🧠 Conceptual

intermediate

Purpose of triggers in Azure DevOps pipelines

What is the main purpose of the 'trigger' keyword in an Azure DevOps YAML pipeline?

A To specify when the pipeline should automatically start based on branch changes

B To define the build agent pool to use

C To set environment variables for the pipeline

D To list the tasks to run in the pipeline

💡 Hint

Think about what causes the pipeline to run automatically.

The 'trigger' keyword defines which branches or paths cause the pipeline to start automatically when code is pushed.

🔀 Workflow

advanced

Correct order of steps in a build pipeline

Arrange these steps in the correct order for a typical Azure DevOps build pipeline.

A 4,2,1,3

B 2,1,4,3

C 2,4,1,3

D 1,2,4,3

💡 Hint

Think about what must happen before building and testing.

First, source code must be checked out, then built, then tested, and finally artifacts are published.

❓ Troubleshoot

advanced

Diagnosing a failed pipeline due to missing agent pool

An Azure DevOps pipeline fails immediately with the error: 'No agent found in pool Default'. What is the most likely cause?

A The repository URL is invalid

B The pipeline YAML syntax is incorrect

C The build script has a runtime error

D The specified agent pool 'Default' has no available agents to run the job

💡 Hint

Consider what the error message says about the agent pool.

The error means the pipeline cannot find any active agents in the specified pool to run the job.

✅ Best Practice

expert

Recommended practice for storing secrets in Azure DevOps pipelines

Which is the best practice for securely using passwords or API keys in Azure DevOps pipelines?

A Save secrets in a public repository file and read them during the build

B Store secrets in pipeline variables marked as secret and reference them in the YAML

C Send secrets as plain text in pipeline logs for debugging

D Hardcode secrets directly in the YAML file for easy access

💡 Hint

Think about how to keep secrets safe and hidden.

Marking variables as secret hides their values in logs and protects them during pipeline runs.

Practice

1. What is the main purpose of a build pipeline in Azure DevOps?

easy

A. To manually test code changes

B. To store code in a repository

C. To automate the process of preparing code for deployment

D. To monitor user activity on a website

Solution

1. Step 1: Understand the role of a build pipeline

   A build pipeline automates tasks like compiling code and running tests when code changes.

2. Step 2: Identify the main goal

   The main goal is to prepare code automatically for deployment or further steps.

3. Final Answer:

   To automate the process of preparing code for deployment -> Option C

4. Quick Check:

   Build pipeline purpose = automate code preparation [OK]

Hint: Build pipelines automate code prep, not manual tasks [OK]

Common Mistakes:

• Confusing build pipeline with code repository
• Thinking build pipelines monitor user activity
• Assuming build pipelines are for manual testing

2. Which YAML snippet correctly defines a trigger for a build pipeline on the 'main' branch?

easy

A. trigger:\n branches:\n - main

B. trigger:\n branches:\n exclude:\n - main

C. trigger:\n paths:\n include:\n - main

D. trigger:\n branches:\n include:\n - main

Solution

1. Step 1: Understand trigger syntax in YAML

   The trigger block uses 'branches' with 'include' to specify branches that start the pipeline.

2. Step 2: Check each option

   trigger:\n branches:\n include:\n - main correctly includes 'main' branch under 'branches' and 'include'. trigger:\n branches:\n exclude:\n - main excludes 'main', which disables trigger on it. trigger:\n paths:\n include:\n - main uses 'paths' which triggers on file changes, not branches. trigger:\n branches:\n - main misses 'include' keyword, so syntax is incorrect.

3. Final Answer:

   trigger:\n branches:\n include:\n - main -> Option D

4. Quick Check:

   Correct trigger syntax includes branches: include [OK]

Hint: Use 'branches: include:' to trigger on specific branches [OK]

Common Mistakes:

• Using 'exclude' instead of 'include' to trigger
• Confusing 'paths' with 'branches' in triggers
• Omitting 'include' keyword causing syntax errors

3. Given this YAML snippet in an Azure build pipeline, what will be the output of the script step?

steps:
- script: echo Hello, Azure DevOps!
  displayName: 'Print greeting'

medium

A. No output, script step is missing

B. Hello, Azure DevOps!

C. script: echo Hello, Azure DevOps!

D. Print greeting

Solution

1. Step 1: Understand the script step in YAML

   The 'script' keyword runs the command given, here 'echo Hello, Azure DevOps!'.

2. Step 2: Identify the output of the echo command

   The echo command prints the text 'Hello, Azure DevOps!' to the pipeline logs.

3. Final Answer:

   Hello, Azure DevOps! -> Option B

4. Quick Check:

   Script echo output = Hello, Azure DevOps! [OK]

Hint: Script runs commands; echo prints text to output [OK]

Common Mistakes:

• Confusing displayName with output
• Thinking script keyword prints itself
• Assuming no output if displayName is set

4. You wrote this YAML snippet for a build pipeline but it fails to trigger on the 'develop' branch:

trigger:
  branches:
    include:
      - main
steps:
- script: echo Build started

What is the likely cause?

medium

A. The trigger only includes the 'main' branch, not 'develop'

B. The script step is missing a displayName

C. The echo command is incorrect syntax

D. The YAML indentation is invalid

Solution

1. Step 1: Analyze the trigger branches

   The trigger includes only the 'main' branch, so changes in 'develop' won't start the pipeline.

2. Step 2: Check other parts for errors

   The script step is valid without displayName, echo syntax is correct, and indentation looks fine.

3. Final Answer:

   The trigger only includes the 'main' branch, not 'develop' -> Option A

4. Quick Check:

   Trigger branches must include target branch [OK]

Hint: Check trigger branches include all needed branches [OK]

Common Mistakes:

• Assuming script needs displayName to run
• Thinking echo command syntax causes trigger failure
• Ignoring trigger branch filters

5. You want to create a build pipeline that triggers only when files in the 'src/' folder change on the 'release' branch. Which YAML snippet correctly sets this up?

hard

A. trigger:\n branches:\n include:\n - release\n paths:\n include:\n - src/**

B. trigger:\n branches:\n include:\n - release\n paths:\n exclude:\n - src/**

C. trigger:\n branches:\n exclude:\n - release\n paths:\n include:\n - src/**

D. trigger:\n branches:\n include:\n - main\n paths:\n include:\n - src/**

Solution

1. Step 1: Understand branch and path filters

   To trigger on 'release' branch and only when files in 'src/' change, include 'release' in branches and 'src/**' in paths.

2. Step 2: Evaluate each option

   trigger:\n branches:\n include:\n - release\n paths:\n include:\n - src/** correctly includes 'release' branch and 'src/**' path. trigger:\n branches:\n include:\n - release\n paths:\n exclude:\n - src/** excludes 'src/**' so it won't trigger on those files. trigger:\n branches:\n exclude:\n - release\n paths:\n include:\n - src/** excludes 'release' branch, so no trigger on it. trigger:\n branches:\n include:\n - main\n paths:\n include:\n - src/** triggers on 'main' branch, not 'release'.

3. Final Answer:

   trigger:\n branches:\n include:\n - release\n paths:\n include:\n - src/** -> Option A

4. Quick Check:

   Include branch and path filters to trigger correctly [OK]

Hint: Use both branches and paths include to filter triggers [OK]

Common Mistakes:

• Using exclude instead of include for paths
• Triggering on wrong branch
• Forgetting to specify paths filter