Python API Reference

In Python actions, the mdl object is available globally.

Methods

mdl.ret(name, value, type)

Returns a named output.

• name (str): Output name.
• value (Any): Value.
• type (str): string, int, bool, file, directory.

mdl.dep(target)

Declares a dependency.

• target (str): action.name or env.NAME.

mdl.retain()

Used in retainer actions for soft dependencies. Signals that the soft dependency target should be kept.

mdl.is_retained(action_name)

Checks if an action was retained/executed. Useful for weak/soft dependencies. Returns True if the action's output is available, False otherwise.

if mdl.is_retained("optional-action"):
    print("Optional action ran!")

Properties

mdl.actions

Access outputs of other actions (Strong dependency). Raises an error if the action output is missing.

val = mdl.actions["other-action"]["output-name"]

mdl.actions (Weak/Soft Access)

To access outputs safely for soft or weak dependencies, use dictionary methods to avoid errors if the action was pruned.

# Safe access for weak/soft dependencies
outputs = mdl.actions.get("optional-action", {})
val = outputs.get("output-name", "") # Default to empty if missing

mdl.args

Dictionary of arguments.

out = mdl.args.get("output-dir")

mdl.flags

Dictionary of flags (bools).

if mdl.flags.get("debug"): ...

mdl.env

Dictionary of environment variables.

key = mdl.env["API_KEY"]

mdl.sys

System variables.

root = mdl.sys["project-root"]