2.1 Map Operator

The MapOperator is most commonly used to apply a function to input data.

There are two ways to use the MapOperator:

Build a MapOperator with a map function

from dbgpt.core.awel import DAG, MapOperator

with DAG("awel_hello_world") as dag:
    task = MapOperator(map_function=lambda x: print(f"Hello, {x}!"))

Implement a custom MapOperator

from dbgpt.core.awel import DAG, MapOperator

class MyMapOperator(MapOperator[str, None]):
    async def map(self, x: str) -> None:
        print(f"Hello, {x}!")

with DAG("awel_hello_world") as dag:
    task = MyMapOperator()

Examples

Double the number

Create a new file named map_operator_double_number.py in the awel_tutorial directory and add the following code:

import asyncio
from dbgpt.core.awel import DAG, MapOperator

class DoubleNumberOperator(MapOperator[int, int]):
    async def map(self, x: int) -> int:
        print(f"Received {x}, returning {x * 2}")
        return x * 2

with DAG("awel_double_number") as dag:
    task = DoubleNumberOperator()  
assert asyncio.run(task.call(2)) == 4

And run the following command to execute the code:

poetry run python awel_tutorial/map_operator_double_number.py

And you will see "Received 2, returning 4" printed to the console.

Received 2, returning 4