10 Golang Global Variables Best Practices

Golang is a powerful programming language that is used for a variety of applications. One of the most important aspects of Golang is its use of global variables. Global variables are variables that are accessible from any part of the program, and they can be used to store data that needs to be accessed from multiple functions.

However, global variables can also be a source of bugs and security vulnerabilities if they are not used correctly. In this article, we will discuss 10 best practices for using global variables in Golang. By following these best practices, you can ensure that your code is secure and efficient.

1. Use global variables only when absolutely necessary

Global variables are accessible from anywhere in the code, which can lead to unexpected behavior and bugs. It’s also difficult to debug code that uses global variables because it’s hard to track down where they’re being used.

Additionally, global variables make your code less modular and more tightly coupled, making it harder to maintain and test. Finally, using global variables makes it difficult to scale your application since you have to keep track of all the different places they’re used.

For these reasons, it’s best to use global variables only when absolutely necessary. If possible, try to avoid them altogether by using local variables or functions instead.

2. Avoid using package level variables as much as possible

Package level variables are global to the package, meaning they can be accessed by any code within that package. This makes them difficult to debug and maintain because it’s hard to keep track of where they’re being used and how they’re being modified.

Additionally, using package level variables can lead to unexpected behavior in your code due to their shared nature. For example, if two functions both use a package level variable, one function could modify the value without the other knowing, leading to unexpected results.

To avoid these issues, try to limit the use of package level variables as much as possible. If you do need to use them, make sure to document their usage clearly so others know what is going on.

3. Always initialize the global variable with a value

When a global variable is declared without an initial value, it will be assigned the zero-value of its type. This can lead to unexpected behavior in your code if you’re not aware that this has happened. By explicitly assigning a value to the global variable when declaring it, you ensure that the expected value is always present and avoid any potential bugs.

4. Never use := to declare and initialize a global variable

When you use := to declare and initialize a global variable, it creates a new local variable in the current scope. This means that any changes made to the global variable will not be reflected outside of the current scope. As such, using := for global variables can lead to unexpected behavior and should be avoided.

Instead, always use the var keyword when declaring and initializing global variables. This ensures that the global variable is accessible from all scopes and any changes made to it are reflected everywhere.

5. Declare all global variables at the top of the file

Declaring global variables at the top of a file makes them easier to find and reference. It also helps keep your code organized, which is important for readability and maintainability. Additionally, declaring all global variables in one place can help you avoid naming conflicts between different variables. Finally, it’s good practice to declare global variables before any other code so that they are available throughout the entire program.

6. Keep related global variables together

When you have related global variables, it’s easier to keep track of them and make sure they are all being used correctly. It also makes the code more readable and understandable for other developers who may be working on the same project. This is especially important when dealing with large projects that involve multiple teams or developers.

By keeping related global variables together, you can ensure that everyone is on the same page and that any changes made to one variable will not affect another. This helps reduce errors and bugs in your code, which can save time and money in the long run.

7. Don’t use short names for global variables

Short names can be easily confused with other variables, leading to errors and bugs. Longer names are more descriptive and make it easier for developers to understand the purpose of a variable at a glance. This is especially important when working in teams or on large projects where multiple people may need to access the same codebase.

Additionally, using longer names helps reduce the risk of namespace collisions. If two different packages have global variables with the same name, they will conflict and cause unexpected behavior. By using unique, descriptive names, you can avoid this issue altogether.

8. Prefix global variables with g_ or glb_

By prefixing global variables with g_ or glb_, you make it easier to identify them in your code. This helps prevent accidental changes to the variable’s value and makes debugging much simpler. It also allows other developers to quickly understand what type of data is stored in a particular variable.

Additionally, by using a consistent naming convention for global variables, you can ensure that all of your code follows the same standards. This will help keep your codebase organized and maintainable over time.

9. Document your global variables

When you document your global variables, it helps other developers understand what they are used for and how to use them. This is especially important if the codebase is large and complex. Without documentation, it can be difficult to figure out which global variable does what and when it should be used.

Documenting global variables also makes it easier to maintain the codebase in the future. If a developer needs to make changes to the code, they will have an easier time understanding the purpose of each global variable and how it fits into the overall architecture.

10. Follow naming conventions for global variables

When you use global variables, it’s important to make sure that they are easily identifiable and distinguishable from other variables. This is especially true when working with a large codebase or multiple developers. By following the naming conventions for global variables, you can ensure that everyone on your team knows which variables are global and which ones aren’t.

For example, in Golang, all global variables should start with an uppercase letter. This makes them easy to spot and helps prevent confusion between local and global variables. Additionally, it’s also good practice to include a comment above each global variable explaining what it does and why it exists. This will help future developers understand the purpose of the variable and how it fits into the overall program.