Polyglot script

Run a script in your language of choice on an agent.

The script runs on an agent with the polyglot capability. The managed environments have one, with bash, Python, JavaScript and Go.

• Kind: code
• Palette: Activities
• Run it on its own: yes

When to use

• Logic that reads better in a programming language: parsing, calling an SDK, a loop that keeps state.
• A script you already have, dropped into a graph unchanged.

To reshape a value between two steps (rename fields, filter a list, join it into a string), a transform is lighter: it runs in the engine and needs no agent. A command line or two is a shell step.

Configuration

Field	Type	Required	Description
script	string	yes	The script source to run.
credentials	object	no	Named credentials injected as env vars: {ENV_VAR: credential_name}.
env	object	no	Extra environment variables, as a JSON object.
interpreter	array	no	Interpreter argv, e.g. [“python3”] (default bash).
optional_when_untrusted	boolean	no	Run without the credential when the run is untrusted (a fork pull request), instead of failing. The credential is still withheld.
outputs	object	no	Rename what comes out: {output_name: key_in_the_raw_output}. Absent passes the raw output through.

Output

An object whose keys depend on the configuration.

Example

version: hyperspool-graph/v1
nodes:
  - id: stats
    type: code
    config:
      interpreter: [python3]
      env:
        REPO: { $expr: "input.repo" }
      script: |
        import json, os, subprocess, urllib.request
        repo = json.load(urllib.request.urlopen(f"https://api.github.com/repos/{os.environ['REPO']}"))
        out = {"stars": repo["stargazers_count"], "open_issues": repo["open_issues_count"]}
        subprocess.run(["spool", "output", "set", "--values", json.dumps(out)], check=True)
  - id: report
    type: shell
    config:
      run: { $template: "echo {{ nodes.stats.output.stars }} stars" }
edges:
  - { from: stats, to: report }

The script sets its output with spool output set, and the next step reads nodes.stats.output.stars. Without interpreter the script runs in bash, under bash -eu. See Polyglot scripts for the durable calls a script can make.

See the node reference for every other node.