Version Control
Version control, also known as source control or revision control, is a software development practice for managing and tracking changes to code and other files. It is a system that records modifications to a file or set of files, allowing software teams to oversee code changes as needed. Version control systems (VCS) provide visibility to the code history and a single source of documentation for all files, folders, and messages. Version control is important because it:
Manages and Protects Source Code It helps manage the source code for the software team by tracking code modifications and protecting the source code from unintended human errors.
Tracks Modifications It records changes for future references and can be used to discover the root cause of a problem.
Enables Comparison of Earlier Versions Developers can go back and compare earlier versions of the code to fix mistakes and reduce disruption to team members.
Facilitates Collaboration It helps teams avoid conflicts and create opportunities to experiment and innovate.
Improves Code Quality It encourages developers to follow best practices and write clean, accessible, understandable, and maintainable code.
Reduces Errors Version control allows developers to find errors quickly and revert to previous versions to correct problems.
Accelerates Product Delivery Version control can help you develop and ship products faster.
Enables Fast and Clear Communication Version control systems enable fast and clear communication between teams and developers.
Helps to Recover Quickly Every code change is tracked, restorable, and revertible, preventing accidental code deletions.
Version Control @ Team Health
Version control is essential for the overall health of the software development life cycle, improving project management and product development. Version control systems help manage conflicts between team members in several ways:
Enabling concurrent work Version control allows team members to work on different features or fixes simultaneously by using branches to isolate their changes.
Managing code conflicts Version control systems provide methods for quickly identifying and solving disputes that arise when multiple developers make changes to a single part of a codebase1. The VCS informs programmers of the conflict and provides options for resolving the issue, such as selecting one developer’s enhancements or merging the two sets of modifications.
Clear record of changes Every modification to the codebase is documented, along with who made the change and why. This transparency helps team members understand the evolution of the project and makes it easier to identify when and where issues were introduced.
Frequent integration Encouraging developers to commit and push their changes frequently helps reduce the likelihood of conflicts and ensures that conflicts are detected and resolved early.
Version reverting In situations where a change exposes problems or creates unexpected issues, the ability to roll back to an earlier version of the source code can be extremely useful.
Merge conflict resolution When merge conflicts occur, version control tools can identify and resolve them4. Tools offer commands such as
git mergeandgit rebaseto handle conflicts, along with visual tools that provide a clear view of conflicting changes.
Branching and Merging of Code
Branching and merging are fundamental aspects of version control systems that facilitate parallel development and integration of changes.
Branching: Branching is the process of creating a separate, independent line of development from a main codebase. When a developer creates a branch, the version control system essentially makes a copy of the codebase at a specific point in time, allowing the developer to work on new features, bug fixes, or experiments without affecting the main codebase.
Merging: Merging is the process of integrating the changes from one branch into another. Once the work on a branch is complete and has been reviewed and tested, it can be merged back into the main branch or another feature branch. Merging combines the changes from the specified branch into the current branch, resolving any conflicts that may arise. Here's how branching and merging typically work:
Create a branch: A developer creates a new branch from the main branch to work on a specific feature or bug fix.
Work on the branch: The developer makes changes to the code on the branch, committing the changes to the branch's history.
Merge the branch: Once the work on the branch is complete, the developer merges the branch back into the main branch. This can be done using a merge request or pull request, which allows other developers to review the changes before they are merged.
Resolve conflicts: During the merging process, conflicts may arise if multiple developers have made changes to the same file. In this case, the developer merging the branch needs to resolve the conflicts by choosing which changes to keep or combining the changes in a way that makes sense5.
Test the merged code: After the branch has been merged, it is important to test the merged code to ensure that it works as expected and that no new bugs have been introduced.
Delete the branch: Once the branch has served its purpose and its changes have been merged into the main codebase, the branch can be safely deleted.
Tool Support
Several version control tools can be used to manage product source code. These tools help track changes, collaborate effectively, and maintain a history of modifications. Here are some popular options:
Git: A distributed version control system that allows developers to manage source code history and collaborate with their team on a project in a decentralized manner. Git is highly customizable and known for its speed and reliability.
Apache Subversion (SVN): A centralized version control system designed to help software development teams manage and track changes to their code. Subversion is scalable, efficient, and easy to use, supporting various platforms and programming languages.
AWS CodeCommit: A source code version control tool provided by AWS that offers speedy source code access, manages commits, and tracks code changes. It securely stores source code and binaries and integrates with existing Git tools.
Azure DevOps: An enterprise server for teams to share code, track work, and ship software for any language in a single package. It integrates with third-party plugins and can be used for tasks like saving search queries, logging bugs, making tests, creating user stories, and building deployments.
Beanstalk: An all-in-one tool that allows users to code, commit, review, and deploy using a browser. It supports both Git and SVN and includes a versatile deployment system with built-in analytics features.
When selecting a version control tool, consider factors such as the size of your team, the complexity of your project, and your preferred workflow. Also, integrations with other development tools, pricing, and the availability of features like branching and merging are important.
Understaing GIT
Git is an open-source distributed version control system (VCS) that helps software teams manage projects of all sizes with efficiency, speed, and asynchronicity. It is a system that records changes to a file or set of files over time so that you can recall specific versions later. Git is known for its speed, workflow compatibility, and open-source foundation. Software development teams prefer Git over other version control systems because of its adaptability, speed, and stability. It's no wonder that 87.2% of developers use Git for version control1.
How Git Works
Git tracks changes to a file or set of files over time, allowing you to recall specific versions later. It is a distributed system, so each user maintains a local copy, or clone, of the repository, including its entire history. Each clone serves as a backup, eliminating any single point of failure. Most operations are carried out locally, so they're not impacted by network latency issues, and users can work whether or not they're connected to the network. After users commit their changes locally, they can push them out to a central repository or to other users' repositories. Other team members can then pull the updated files to their own systems to ensure they're working with the latest version. Git has three file states:
Modified: The file has been changed but isn't committed to the database yet.
Staged: The file is set to go into the next commit.
Committed: The data has been stored in the database.
Benefits of Git
Tracks Modifications It records changes for future references and can be used to discover the root cause of a problem.
Enables Comparison of Earlier Versions Developers can go back and compare earlier versions of the code to fix mistakes and reduce disruption to team members.
Facilitates Collaboration It helps teams avoid conflicts and create opportunities to experiment and innovate.
Improves Code Quality It encourages developers to follow best practices and write clean, accessible, understandable, and maintainable code.
Reduces Errors Version control allows developers to find errors quickly and revert to previous versions to correct problems.
Accelerates Product Delivery Version control can help you develop and ship products faster.
Creates a Single Source of Truth Version control systems create a complete codebase history, stored in a specialized database, and provide the entire team with a single and secure source of truth.
Enables Fast and Clear Communication Version control systems enable fast and clear communication between teams and developers.
Helps to Recover Quickly Every code change is tracked, restorable, and revertible, preventing accidental code deletions.
Workflow Flexibility Teams can work together using various branching strategies.
Speed Users have a local repository on their machine with a full history, so there's no lag in communicating with a server.
Reliability Git inherently has multiple backups, because each user has a local repository.
Git Operations
With Git, software teams can experiment without fearing that they'll create lasting damage to the source code because teams can always revert to a previous version if there are any problems. Git also makes it easy to undo changes during the three main states1. Most Git actions only add data to the database1. Some common Git operations include:
Creating, merging, and deleting branches quickly.
Committing changes locally.
Pushing changes to a central repository or other users' repositories.
Pulling changes from a central repository or other users' repositories.
Reverting selected files back to a previous state.
Reverting the entire project back to a previous state.
Comparing changes over time.
Identifying who last modified something that might be causing a problem.
Practice
Do-It-yourself exercies on GIT are here
GIT Commands - https://git-scm.com/docs/git
GIT Download - https://git-scm.com/docs/git
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