Quickstart guide¶

In this guide, you will create and run a Flyte workflow in a local Python environment to generate the output “Hello, world!”

Prerequisites¶

Install Python 3.8x or higher
Install Flytekit with pip install -U flytekit

Steps¶

1. Create a “Hello, world!” file¶

To create an example workflow file, copy the following into a file called example.py:

from flytekit import task, workflow


@task
def say_hello(name: str) -> str:
    return f"Hello, {name}!"


@workflow
def hello_world_wf(name: str = 'world') -> str:
    res = say_hello(name=name)
    return res


if __name__ == "__main__":
    print(f"Running wf() {hello_world_wf(name='passengers')}")

Note

You can also use the pyflyte init command to initialize the “Hello, world!” Flyte project by running the following command:

pyflyte init --template hello-world hello-world

This will create a project directory that contains an example.py file with code above.

2. Run the example workflow in a local Python environment¶

Next, run the workflow in the example workflow file with pyflyte run. The initial arguments of pyflyte run take the form of path/to/script.py <task_or_workflow_name>, where <task_or_workflow_name> refers to the function decorated with @task or @workflow that you wish to run:

pyflyte run example.py hello_world_wf

You can also provide a name argument to the workflow:

pyflyte run example.py hello_world_wf --name Ada

Note

If you created a “Hello, world” project using pyflyte init, you will need to change directories before running the workflow:

cd hello-world
pyflyte run example.py hello_world_wf

The @task and @workflow decorators¶

In this example, the file example.py contains a task and a workflow, decorated with the @task and @workflow decorators, respectively. You can invoke tasks and workflows like regular Python methods, and even import and use them in other Python modules or scripts.

@task
def say_hello(name: str) -> str:
    return f"Hello, {name}!"


@workflow
def hello_world_wf(name: str = 'world') -> str:
    res = say_hello(name=name)
    return res

To learn more about tasks and workflows, see the “Workflow code” section of “Flyte project components”.

Next steps¶

To create a productionizable Flyte project to structure your code according to software engineering best practices, and that can be used to package your code for deployment to a Flyte cluster, see “Getting started with workflow development”.