Skip to main content

Open a Browser from Automation Scripts

· 2 min read
Erik Osterman
Erik Osterman
Founder @ Cloud Posse

A custom command that starts a local dashboard usually ends by opening it. Doing that portably has meant detecting the operating system and shelling out to open, xdg-open, or start, each with its own quoting rules and failure modes. Atmos automation scripts can now call browser.open to open a URL in the default browser on any platform.

The Problem​

Opening a URL is one of the most common last steps in developer tooling: a local portal, a docs preview, a login page. Scripts had no built-in way to do it, so each command carried its own operating-system check and passed the URL through a shell, where a stray character could change what was run.

The Fix​

The new browser.open(url) function uses the same cross-platform browser launcher Atmos already uses elsewhere. It accepts only absolute HTTP or HTTPS URLs without embedded credentials, so local file paths, javascript: URLs, and argument-like strings are rejected before anything launches. Launch failures fail the script with a clear error, and dry runs never open a browser.

How to Use It​

Add it to any script step or standalone script:

commands:
  - name: portal
    commands:
      - name: open
        description: Open the local dashboard
        steps:
          - type: script
            interpreter: starlark
            script: |
              browser.open("http://localhost:3000")

Then run atmos portal open. The function is also available inside helpers loaded with module.load.

Get Involved​

Try it in your own custom commands and let us know what else your scripts need on GitHub or in the Cloud Posse community Slack.