AZ-400 Design and implement a source control strategy Practice Test 4 — 15 Questions

Question 1

Your team uses Git with Azure Repos. You notice that the commit history on the main branch contains many merge commits and commit messages like 'fix merge conflict'. You want a linear history for better traceability. What should you change?

Accepted Answer

Use squash merge when completing pull requests. Option D is correct because squash merge collapses all feature branch commits into a single commit on the main branch, eliminating merge commits and preserving a linear history. This directly addresses the problem of cluttered commit messages like 'fix merge conflict' by discarding intermediate commits and their messages. Squash merge is configured in the Azure Repos branch policy for pull request completion.

Answer

Configure the repository to use rebase when pulling

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Set the branch policy to require a clean fast-forward merge

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Use rebase merge when completing pull requests

Question 2

Your organization uses Azure Repos and requires that all code changes pass a security scan before merging. The scan is run as a build validation policy. However, the scan takes 30 minutes and developers often bypass it by pushing directly to main. How can you enforce the policy for all changes?

Accepted Answer

Set a branch policy on main that requires a build validation with the security scan. Option C is correct because setting a branch policy on main that requires a build validation with the security scan enforces the scan as a mandatory gate for all pull requests targeting main. This prevents developers from bypassing the scan by pushing directly, as the policy blocks direct pushes and only allows changes through pull requests that must pass the configured build validation.

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Turn off direct push permissions for all users and force all changes through pull requests

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Delete the main branch and recreate it as a protected branch

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Use a service hook to run the scan on every push to main

Question 3

Your team uses GitHub for source control. You need to ensure that sensitive data, such as connection strings, is never committed to the repository. Which tool should you use?

Accepted Answer

GitHub secret scanning. GitHub secret scanning automatically detects sensitive data like connection strings, API keys, and tokens as they are pushed to a repository, preventing them from being committed. It scans for known patterns and can block the push or alert the repository administrator, making it the correct tool for this requirement.

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GitHub Actions

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Dependabot

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Git Large File Storage (LFS)

Question 4

You work for a multinational company that uses Azure Repos. The compliance team requires that all code changes include a work item reference in the commit message. What is the most effective way to enforce this?

Accepted Answer

Set a branch policy that requires a linked work item for pull requests. Option C is correct because a branch policy in Azure Repos that requires linked work items for pull requests enforces the compliance requirement at the server side, ensuring that every pull request merge includes a work item reference. This policy is enforced before the merge completes, making it a reliable and auditable method that cannot be bypassed by individual developers. It directly integrates with Azure Boards to validate the link, providing a centralized enforcement mechanism.

Answer

Create a script in the build pipeline that checks the commit message

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Configure a client-side commit hook that validates the commit message

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Use a custom build task to automatically add the work item ID to the commit message

Question 5

Your organization is migrating from Azure Repos to GitHub. You have 200 repositories with complex branching strategies and build policies. You need to preserve the commit history and branch policies. What is the best migration approach?

Accepted Answer

Use the GitHub Importer tool with a custom mapping script to migrate repositories and policies. The GitHub Importer tool, combined with a custom mapping script, is the correct approach because it can migrate repositories along with their commit history and branch policies from Azure Repos to GitHub. This tool handles the complex branching strategies and build policies by allowing you to define mappings for users, branches, and policies, ensuring a seamless transition without manual recreation or data loss.

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Manually recreate each repository in GitHub and copy the code from Azure Repos

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Use a third-party tool to perform a mirror clone and then push to GitHub

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Use git push --force to push all branches to GitHub and recreate policies manually

Question 6

Your development team uses GitHub for source control. You want to automatically run a set of tests every time a pull request is opened against the main branch. What should you configure?

Accepted Answer

Create a GitHub Actions workflow triggered by pull_request events to main. Option A is correct because GitHub Actions natively supports the `pull_request` event trigger, which can be configured to run workflows automatically when a pull request is opened against a specific branch (e.g., `main`). This allows you to define a YAML-based workflow in the `.github/workflows` directory that executes tests on every PR event, providing immediate feedback to developers without requiring external services or manual API calls.

Answer

Use the GitHub API to trigger tests when a PR is opened

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Set up a webhook to trigger an external CI system

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Configure a branch protection rule to require status checks

Question 7

Your team uses Azure Repos with a Git branching strategy. You need to ensure that all changes to the release branch are reviewed by at least two approvers and that builds succeed before merging. Which TWO branch policy settings should you enable?

Accepted Answer

Build validation. Option B (minimum number of reviewers) and Option C (build validation) are correct. Option A is wrong because it's not a standard policy. Option D is wrong because it's for linear history. Option E is wrong because it's not a policy setting.

Answer

Work item linking

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Require a clean fast-forward merge

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Require a merge commit

Question 8

Your organization uses GitHub for source control. You need to implement a secure source control strategy that prevents secrets from being exposed and ensures code quality. Which THREE practices should you implement?

Accepted Answer

Configure branch protection rules requiring status checks to pass. Option A is correct because branch protection rules enforce required status checks (e.g., CI builds, code reviews) before merging, which prevents code that fails quality gates from entering protected branches. This directly supports code quality by ensuring only validated changes are merged.

Answer

Store secrets in a .env file committed to the repository

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Require commit signing using GPG keys

Question 9

Your team uses Git for source control. You want to maintain a clean commit history on the main branch by avoiding merge commits. Which TWO merge strategies in a pull request achieve this?

Accepted Answer

Rebase merge. A rebase merge (option A) rewrites the commit history of the feature branch onto the tip of the target branch, creating a linear sequence of commits without any merge commits. This maintains a clean, linear history on the main branch. A squash merge (option C) combines all commits from the feature branch into a single new commit on the target branch, also avoiding merge commits and keeping the history clean.

Answer

Merge commit

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Three-way merge

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Fast-forward merge

Question 10

Your team uses GitHub for source control and wants to enforce that all pull requests into the main branch require at least two reviewers and must pass a status check from a CI pipeline. Which branch protection rule configurations should you apply?

Accepted Answer

Require a minimum of 2 reviewers, require status checks to pass before merging. Option A is correct because GitHub branch protection rules allow you to require a minimum number of reviewers before merging and to require status checks to pass. By setting 'Require a minimum number of reviewers' to 2 and enabling 'Require status checks to pass before merging', you enforce that every pull request into the main branch must be approved by at least two reviewers and must pass the CI pipeline status check, meeting the stated requirements.

Answer

Require signed commits and status checks

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Require status checks to pass, but do not require reviewers

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Require a minimum of 2 reviewers, but do not require status checks

Question 11

You are designing a branching strategy for a microservices application with independent deployment cadences. The team wants to support continuous deployment to production from the main branch while allowing feature work to be isolated and tested. Which branching strategy best meets these requirements?

Accepted Answer

Trunk-based development with short-lived feature branches. Trunk-based development with short-lived feature branches (C) is correct because it enables continuous deployment from the main branch while isolating feature work in branches that are merged back to main within hours or a day. This approach minimizes merge conflicts and supports independent deployment cadences for microservices, as each service can be deployed from main independently without waiting for release branches.

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One branch per environment (dev, test, prod)

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GitHub Flow with feature branches merging to main

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Git Flow with develop, release, and hotfix branches

Question 12

Your Azure DevOps repository contains a large binary file that is slowing down clone operations. Which Git feature should you use to reduce the clone time?

Accepted Answer

Git LFS (Large File Storage). Git LFS (Large File Storage) is the correct solution because it replaces large binary files in the repository with lightweight text pointers, storing the actual binary content in external remote storage. This prevents the large file from being downloaded during every clone, significantly reducing clone time and repository size on disk.

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Shallow clone

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Depth parameter in clone command

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Sparse checkout

Question 13

Your team uses Azure Repos and needs to prevent secrets from being committed to the repository. Which built-in feature should you enable?

Accepted Answer

Enable push protection in Azure Repos. Push protection in Azure Repos is a built-in feature that scans commits for high-confidence secrets (e.g., Azure service connection strings, SSH keys, and other credential patterns) and blocks the push if a secret is detected. This prevents secrets from ever reaching the remote repository, enforcing security at the server side without requiring client-side configuration.

Answer

Enable GitHub secret scanning

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Enable Azure Policy to scan repositories

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Configure a pre-commit hook with a secret scanning tool

Question 14

Your organization uses GitHub and wants to implement a monorepo strategy for multiple related projects. Which approach best optimizes CI/CD pipeline performance by only building projects that have changed?

Accepted Answer

Use path filters in GitHub Actions workflows. Option D is correct because GitHub Actions path filters (using `on.push.paths` or `on.pull_request.paths`) allow you to trigger workflows only when changes are made to specific directories or files. In a monorepo, this ensures that CI/CD pipelines run exclusively for the projects that have been modified, avoiding unnecessary builds and significantly improving performance.

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Use a single workflow that builds all projects on every push

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Use submodules to separate projects

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Use workflow templates and composite actions

Question 15

You need to enforce that every commit in your repository is associated with a work item in Azure Boards. Which mechanism should you use?

Accepted Answer

Configure a branch policy to require linked work items. Option C is correct because Azure Repos branch policies include a setting to 'Require linked work items', which enforces that every pull request (and by extension, every commit merged through that PR) is associated with a work item in Azure Boards. This policy is enforced server-side at merge time, ensuring no commit can be merged without a linked work item, regardless of how the commit message is formatted.

Answer

Use commit messages with work item IDs

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Deploy a custom Git hook on the server

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Use the 'Require status checks' policy