Source Code Management - How much do you know ?

Source code management is the concept of storing the source code for your software applications in a centralized, managed place. It’s used by software development teams, who are the ones that gain the most benefit from it due to the multiple developers they have.

There are several reasons why we should manage the source code that we write:

• A source code management system allows multiple developers to access and change different areas of the code, without interfering with each other’s work.

• The system will keep a history of all saved changes to the code.

• Code can be linked to a release, and as a result, release notes can be generated.

• Centralized place on a server where the source code is stored ensures there is a main location for the code (other than the developer’s machine).

Some of the key terms used in this process include:

• Check out – gets a writeable copy of the code for a single developer

• Check in – saves the code that has been checked out back into the system, removing any locks placed on it.

• Commit – same as “check in”, just a different term.

• Branch – a different version of some code, created from an earlier release, separate to the main version. Similar to a “tree branch” metaphor – branches out from a certain point to form its own line.

• Merge – combining two or more sets of code together, perhaps as a result of a branch. This process is performed by the source control management system when you need it to.

• Repository – the server and system used to store the source code.

How Does Source Code Management Works ?

The process works by a development team or company having a centralized server that stores all of the required code. This server is called the repository – the storage place for code. It can run various source code management systems, which are used to manage changes and different projects.

The system stores a copy of the source code as individual files, just like the developers have written it. When you want to make changes to some code, you perform what’s called a “check out” on the file. You get your own copy of the file in your environment. It also creates a “lock” on the file on the server, which means others can’t check out the same piece of code. This is to minimize the chances of someone overwriting your work.

Once you’ve made the changes, and tested them, you can save them onto the server using a process called “commit” or “check in”. This saves your code onto the server, replacing the existing file, and incrementing the version. It also removes the lock that was placed previously. You can usually add comments to this process, which allows you to specify what was changed.

This can all be done by different developers on different files. The source code management system will store this code and manage the changes that have been made.