Source code for system.apache.spark.example_pyspark

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from __future__ import annotations

import typing

import pendulum

if typing.TYPE_CHECKING:
    import pandas as pd
    from pyspark.sql import SparkSession

try:
    from airflow.sdk import dag, task
except ImportError:
    # Airflow 2 path
    from airflow.decorators import dag, task  # type: ignore[attr-defined,no-redef]


@dag(
    schedule=None,
    start_date=pendulum.datetime(2021, 1, 1, tz="UTC"),
    catchup=False,
    tags=["example"],
)
def example_pyspark():
    """
    ### Example Pyspark DAG
    This is an example DAG which uses pyspark
    """

    # [START task_pyspark]
    @task.pyspark(conn_id="spark-local")
    def spark_task(spark: SparkSession) -> pd.DataFrame:
        df = spark.createDataFrame(
            [
                (1, "John Doe", 21),
                (2, "Jane Doe", 22),
                (3, "Joe Bloggs", 23),
            ],
            ["id", "name", "age"],
        )
        df.show()

        return df.toPandas()

    # [END task_pyspark]

    @task
    def print_df(df: pd.DataFrame):
        print(df)

    df = spark_task()
    print_df(df)


# work around mypy
dag = example_pyspark()  # type: ignore


from tests_common.test_utils.system_tests import get_test_run  # noqa: E402

# Needed to run the example DAG with pytest (see: contributing-docs/testing/system_tests.rst)
test_run = get_test_run(dag)