Simplify Environment Variable Management with a Bash Script

Tue Jul 02 2024 5 min read

Simplifying Environment Variable Management with a Bash Script

Introduction

Managing environment variables in multiple projects can be a hassle, especially when you need to switch between different .env files. To make this process easier, I’ve created a simple Bash script that helps you sync .env files between your projects and a centralized folder. This blog will guide you through setting up and using the script.

Setting Up the Script

Create the Script File:

Open your terminal and create a new file named env_sync.sh.
```
nano env_sync.sh
```

Copy and paste the following script into the file:

 #!/bin/bash

 # Define paths
 ENV_FOLDER="$HOME/envs"

 # Function to sync .env file from ~/envs based on current directory name
 sync_envs() {
     local action="$1"

     # Get the current directory name (project name)
     local current_dir=$(basename "$(pwd)")
     local pwd=$(pwd)

     case "$action" in
         "copy")
             # Copy .env file to ~/envs/projectname/
             if [ ! -d "$ENV_FOLDER/$current_dir" ]; then
                 mkdir -p "$ENV_FOLDER/$current_dir"
             fi
             echo "$current_dir"
             cp "$pwd/".env* "$ENV_FOLDER/$current_dir/"
             echo ".env* files copied to $ENV_FOLDER/$current_dir/"
             # Git operations
             if [ ! -d "$ENV_FOLDER/$current_dir/.git" ]; then
                 git -C "$ENV_FOLDER/$current_dir" init
             fi
             git -C "$ENV_FOLDER/$current_dir" add .env*
             git -C "$ENV_FOLDER/$current_dir" commit -m "Copied .env* files from $pwd to $ENV_FOLDER/$current_dir/ at $(date)"
             ;;
         "move")
             # Move .env file from ~/envs/projectname/ to current directory
             if ls "$ENV_FOLDER/$current_dir/".env* 1> /dev/null 2>&1; then
                 mv "$ENV_FOLDER/$current_dir/".env* ./
                 echo ".env* files moved from $ENV_FOLDER/$current_dir/ to current directory."
                 # Git operations
                 if [ ! -d "$ENV_FOLDER/$current_dir/.git" ]; then
                     git -C "$ENV_FOLDER/$current_dir" init
                 fi
                 git -C "$ENV_FOLDER/$current_dir" add .env*
                 git -C "$ENV_FOLDER/$current_dir" commit -m "Moved .env* files from $ENV_FOLDER/$current_dir/ to $pwd at $(date)"
             else
                 echo "Error: .env* file not found in $ENV_FOLDER/$current_dir/"
                 exit 1
             fi
             ;;
         *)
             echo "Usage: env_sync [copy|move]"
             exit 1
             ;;
     esac
 }

 # Function to copy .env file from ~/envs based on manually provided directory name
 copy_env_by_name() {
     local dir_name="$1"

     # Check if .env file exists in ~/envs/directory_name/
     if ls "$ENV_FOLDER/$dir_name/".env* 1> /dev/null 2>&1; then
         cp "$ENV_FOLDER/$dir_name/".env* ./
         echo ".env* files copied from $ENV_FOLDER/$dir_name/ to current directory."
         # Git operations
         if [ ! -d "$ENV_FOLDER/$dir_name/.git" ]; then
             git -C "$ENV_FOLDER/$dir_name" init
         fi
         git -C "$ENV_FOLDER/$dir_name" add .env*
         git -C "$ENV_FOLDER/$dir_name" commit -m "Copied .env* files from $ENV_FOLDER/$dir_name/ to current directory at $(date)"
     else
         echo "Error: .env* files not found in $ENV_FOLDER/$dir_name/"
     fi
 }

 # Function to list directories in ~/envs
 list_envs_directories() {
     echo "Directories in $ENV_FOLDER:"
     ls -d $ENV_FOLDER/*/ | xargs -n 1 basename
 }

 # Help function
 show_help() {
     echo "Usage: $0 [option]"
     echo "Options:"
     echo "  copy          Copy .env* from current directory to ~/envs/projectname/"
     echo "  move          Move .env* from ~/envs/projectname/ to current directory"
     echo "  ls            List directories in $ENV_FOLDER"
     echo "  get <dir>     Copy .env* from ~/envs/<dir> to current directory"
     echo "  dir <pattern> List directories in $ENV_FOLDER matching <pattern>"
     echo "  --help        Show this help message"
 }

 # Main script logic
 case "$1" in
     "copy")
         sync_envs copy
         ;;
     "move")
         sync_envs move
         ;;
     "ls")
         list_envs_directories
         ;;
     "get")
         if [ -n "$2" ]; then
             copy_env_by_name "$2"
         else
             echo "Error: Please provide a directory name. Usage: env_sync get directory_name"
             exit 1
         fi
         ;;
     "dir")
         if [ -n "$2" ]; then
             list_envs_directories | grep "$2"
         else
             echo "Error: Please provide a directory name to search. Usage: env_sync dir directory_name"
             exit 1
         fi
         ;;
     "--help")
         show_help
         ;;
     *)
         echo "Error: Invalid option. Use '--help' for usage."
         exit 1
         ;;
 esac

Make the Script Executable:
- After saving the script, make it executable with the following command:
```
chmod +x env_sync.sh
```

Setting Up Aliases

To make the script easily accessible from anywhere, you can set up an alias in your shell configuration file (~/.bashrc for Bash or ~/.zshrc for Zsh).

Open Your Shell Configuration File:
- For Bash:
```
nano ~/.bashrc
```
- For Zsh:
```
nano ~/.zshrc
```
Add the Alias:
- Add the following line to create an alias named envm:
```
alias envm="$HOME/path_to_script/env_sync.sh"
```
- Replace path_to_script with the actual path to where you saved env_sync.sh.
Apply the Changes:
- For Bash:
```
source ~/.bashrc
```
- For Zsh:
```
source ~/.zshrc
```

Using the Script

With the alias set up, you can use the script with the envm command:

Copy .env Files to Central Folder:
```
envm copy
```
Move .env Files from Central Folder to Project Directory:
```
envm move
```
List All Project Directories:
```
envm ls
```
Copy .env Files by Directory Name:
```
envm get <project_name>
```
Search for Directories by Pattern:
```
envm dir <pattern>
```
Show Help:
```
envm --help
```

Important Considerations

Git Operations

The script automatically initializes a Git repository in the central folder if it doesn’t exist and commits changes each time you copy or move .env files. This makes it easy to track changes and revert to previous versions if needed.

Warning: Exposure of `.env` Files

If you add a remote repository and push your changes to GitHub or another Git hosting service, your environment variables could be exposed publicly. To avoid this, make sure to keep the envs folder local and do not push it to a remote repository.

Example Workflow

Initialize a Project:
- Suppose you are working on a project named myproject.
- Navigate to your project directory:
```
cd ~/projects/myproject
```
Copy .env Files to Central Folder:
- Run the script to copy .env files to the central folder:
```
envm copy
```
List Project Directories:
- To see all stored projects in the central folder:
```
envm ls
```
Copy .env Files from a Specific Project:
- If you need to copy .env files from a specific project folder:
```
envm get myproject
```

Conclusion

This script helps streamline the management of environment variables across different projects by providing a simple way to sync .env files. With a few commands, you can copy, move, and list .env files effortlessly. Feel free to customize the script further to suit your workflow needs. By setting up an alias, you can easily use the script from any directory, making your development process more efficient and