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Script-Friendly Output for atmos toolchain get

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

Pulling a tool's version into a script usually means scraping decorated terminal output. A checkmark here, a color code there, maybe a table row — and now the one-liner that used to grab a version string needs a regex, a head -1, and a 2>&1 to work around output that was never meant to be parsed.

The Problem​

A CI job that needs a tool's configured version — to pass to another action, or write to GITHUB_OUTPUT — had to reach for something like:

version=$(atmos toolchain get vale-cli/vale 2>&1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1)
echo "version=$version" >> "$GITHUB_OUTPUT"

That's a lot of shell just to answer "what version is configured?" — a regex to strip a checkmark and color codes, head -1 because the human-readable view can list more than one line, and 2>&1 because the output goes to stderr, not stdout.

The Fix​

atmos toolchain get now supports a --format flag with two script-friendly output modes alongside the existing human-readable table: plain prints just the bare version string, and json prints structured output including whether that version is installed.

How to Use It​

Grab a version with nothing to parse:

$ atmos toolchain get vale-cli/vale --format=plain
2.20.0

Which collapses the CI snippet above to:

version=$(atmos toolchain get vale-cli/vale --format=plain)
echo "version=$version" >> "$GITHUB_OUTPUT"

Ask for more than the version string with --format=json:

$ atmos toolchain get terraform --format=json
{
  "tool": "hashicorp/terraform",
  "version": "1.9.8",
  "installed": false
}

--format=plain only makes sense for a single resolved version, so it's rejected when combined with --all (which lists every available version) — use --format=json there instead, which returns the full list with each entry's installed and default status.

Get Involved​

Try --format=plain or --format=json the next time you're piping a tool version into a script. If you run into a toolchain command that still only prints decorated, hard-to-parse output, please open an issue so we can add the same script-friendly modes there too.