How to Open a macOS App Using Python

Python provides a versatile standard library for automating tasks, including opening applications on macOS. Whether you're building a utility script, automating workflows, or just experimenting with Python's capabilities, opening macOS apps programmatically can be both useful and straightforward.

In this blog post, we'll show you how to open a macOS app using Python's subprocess module. Along the way, we'll explore a practical example by opening Visual Studio Code.

Using subprocess to Open an App

Python’s subprocess module allows you to start new processes and interact with them. Here’s how you can use it to open a macOS app:

import subprocess

# Launch the app
vscode = subprocess.Popen("/Applications/Visual Studio Code.app/Contents/MacOS/Electron")

print("Visual Studio Code has been opened.")

Breaking It Down

1. Locate the App's Executable
   macOS apps are essentially directories with the .app extension. Inside these directories, the actual executable resides. For example:

   • Visual Studio Code’s executable:
     /Applications/Visual Studio Code.app/Contents/MacOS/Electron
   • Safari’s executable:
     /Applications/Safari.app/Contents/MacOS/Safari

   Navigate to the app’s .app directory, drill down to the Contents/MacOS folder, and find the executable file.

2. Launch the Executable with subprocess.Popen
subprocess.Popen() starts the process asynchronously, meaning the Python script continues running while the app launches in the background.

   In our example, the vscode variable holds the process object, which we can use to manage or monitor the application.

Example: Open and Monitor a macOS App

Here’s an extended example that opens Visual Studio Code and checks if it’s still running:

import subprocess

# Start the app
vscode = subprocess.Popen("/Applications/Visual Studio Code.app/Contents/MacOS/Electron")

# Function to check the status of the app
def check_status(process, name):
    if process.poll() is None:
        print(f"{name} is running.")
    else:
        print(f"{name} has exited with code {process.returncode}.")
    return process.poll() is None

# Check the app's status
check_status(vscode, "Visual Studio Code")

Key Points:

• poll(): Checks if the process is still running. Returns None if it’s active or the exit code if it has terminated.
• returncode: Provides the exit code after the process terminates.

Automating Workflows

Let’s say you want to open multiple apps simultaneously or ensure an app is always running. Here’s an example:

import subprocess
import time

# List of apps to open
apps = [
    ("/Applications/Visual Studio Code.app/Contents/MacOS/Electron", "Visual Studio Code"),
    ("/Applications/Safari.app/Contents/MacOS/Safari", "Safari"),
]

# Start apps
processes = [(subprocess.Popen(app[0]), app[1]) for app in apps]

# Monitor apps
while True:
    for process, name in processes:
        if process.poll() is None:
            print(f"{name} is running.")
        else:
            print(f"{name} has stopped.")
            processes.remove((process, name))  # Remove terminated processes
    if not processes:
        print("All apps have exited.")
        break
    time.sleep(5)

Conclusion

Opening macOS apps with Python is simple and powerful. By leveraging the subprocess module, you can start applications, monitor their status, and integrate them into larger automation scripts. Whether you're managing a single app or orchestrating multiple applications, this approach can save time and effort.

Start experimenting today, and let Python handle your app-launching needs! Have any tips, tricks, or questions? Share them in the comments below. 🚀