How to access deployment and flow run parameters

from prefect import flow


@flow
def alpha(name: str, value: int):
    print(name, value)


@flow
def beta(name: str, value: int, another: float):
    print(name, value, another)

from datetime import timedelta

from prefect.automations import (
    Automation,
    EventTrigger,
    Posture,
    ResourceSpecification,
    RunDeployment,
)

from .flows import alpha, beta

# Note: deploy these flows in the way you best see fit for your environment
alpha.deploy(
    name="alpha",
    work_pool_name="my-work-pool",
    image="prefecthq/prefect-client:3-latest",
)
beta_deployment_id = beta.deploy(
    name="beta",
    work_pool_name="my-work-pool",
    image="prefecthq/prefect-client:3-latest",
)

automation = Automation(
    name="Passing parameters",
    trigger=EventTrigger(
        # Here we're matching on every completion of the `alpha` flow
        expect={"prefect.flow-run.Completed"},
        match_related=ResourceSpecification(
            {
                "prefect.resource.role": "flow",
                "prefect.resource.name": "alpha"
            }
        ),
        # And we'll react to each event immediately and individually
        posture=Posture.Reactive,
        threshold=1,
        within=timedelta(0),
    ),
    actions=[
        RunDeployment(
            # We will be selecting a specific deployment (rather than attempting to
            # infer it from the event)
            source="selected",
            # The deployment we want to run is the `beta` deployment we created above
            deployment_id=beta_deployment_id,
            parameters={
                # For the "name" and "value" parameters, we tell Prefect we're using a
                # Jinja2 template by creating a nested dictionary with the special
                # `__prefect_kind` key set to "jinja".  Then we supply the `template`
                # value with any valid Jinja2 template.  This step may also be done
                # in the Prefect UI by selecting "Use Jinja input" for the parameters
                # you want to template.
                #
                # The "{{ flow_run }}" variable here is a special shortcut that gives us
                # access to the `FlowRun` object associated with this event.  There are
                # also variables like "{{ deployment }}", "{{ flow }}",
                # "{{ work_pool }}" and so on.
                #
                # In this case, the {{ flow_run }} represent the run of `alpha` that
                # emitted the `prefect.flow-run.Completed` event that triggered this
                # automation.
                "name": {
                    "template": "{{ flow_run.parameters['name'] }}",
                    "__prefect_kind": "jinja",
                },
                "value": {
                    "template": "{{ flow_run.parameters['value'] }}",
                    "__prefect_kind": "jinja",
                },
                # You can also just pass literal parameters
                "another": 1.2345,
            },
        )
    ],
).create()