Skip to main content

ctx.arguments

The ctx.arguments value is a read-only dictionary of the positional arguments Atmos parsed for a custom command, keyed by each argument's declared name.

Usage​

ctx.arguments["name"]

Returns​

A frozen dictionary with sorted keys. In a custom command it has one entry for each argument the command declares, with the value the user typed. In a workflow step, a hook, or a standalone script it is an empty dictionary. A standalone program receives its arguments as the args argument of the entry function it passes to cli.command.

Steps inside parallel and matrix groups inherit the dictionary.

Examples​

Read a declared argument​

commands:
  - name: greet
    arguments:
      - name: name
        description: Who to greet
        required: true
    steps:
      - name: greet
        type: script
        interpreter: starlark
        script: |
          print("Hello, {}!".format(ctx.arguments["name"]))
atmos greet Ada
Hello, Ada!

Combine arguments and flags​

service = ctx.arguments["service"]
replicas = int(ctx.flags["replicas"])
print("{}: {} replicas".format(service, replicas))

Fail early on a missing value​

if not ctx.arguments.get("service"):
    fail("a service name is required")

Related​