Defining launch plans#

You can define a launch plan with the flytekit.LaunchPlan class.

For example:

from flytekit import task, workflow, LaunchPlan

@task
def my_task(a: int, b: int, c: int) -> int:
    return a + b + c

@workflow
def my_workflow(a: int, b: int, c: int) -> int:
    return my_task(a=a, b=b, c=c)

LaunchPlan.get_or_create(
    workflow=my_workflow,
    name="my_workflow_custom_lp",
    fixed_inputs={"a": 3},
    default_inputs={"b": 4, "c": 5}
)

In this example, we define a task my_task and a workflow my_workflow. We then define a launch plan for my_workflow. The launch plan is declared by calling LaunchPlan.get_or_create with the workflow name, launch plan name, and the desired default and fixed inputs. If you do not supply a launch plan name, the default launch plan (which has the same name as the workflow) is assumed.

Note

In the above code the LaunchPlan object returned by get_or_create() is not assigned to a variable. However, you can assign the launch plan object to a variable and reference the variable elsewhere in your code, allowing you to control when the launch plan is invoked. For more details, see [Running Launch Plans)(running-launch-plans).

Launch plan inputs#

A launch plan can be defined with:

Some (or all) workflow inputs unspecified. These must be provided at execution time. In the UI, they appear in the Launch Workflow dialog as empty input fields.
Some (or all) workflow inputs specified as default, with values. These may be provided as overrides at execution time, but if not, the default values are used. In the UI, they appear in the Launch Workflow dialog as pre-filled input fields that can be changed.
Some (or all) workflow inputs specified as fixed, with values. These cannot be overridden at execution time. They are not shown in the Launch Workflow dialog.