Using PySpark on a cluster requires all cluster nodes to have those Python packages installed that are required by the PySpark job. Such a deployment can be cumbersome, especially when running in an interactive notebook.
The spark-extension
package allows installing Python packages programmatically by the PySpark application itself (PySpark ≥ 3.1.0).
These packages are only accessible by that PySpark application, and they are removed on calling spark.stop()
.
Either install the spark-extension
Maven package, or the pyspark-extension
PyPi package (on the driver only),
as described here.
Python packages can be installed with pip
as follows:
# noinspection PyUnresolvedReferences
from gresearch.spark import *
spark.install_pip_package("pandas", "pyarrow")
Above example installs PIP packages pandas
and pyarrow
via pip
. Method install_pip_package
takes any pip
command line argument:
# install packages with version specs
spark.install_pip_package("pandas==1.4.3", "pyarrow~=8.0.0")
# install packages from package sources (e.g. git clone https://github.com/pandas-dev/pandas.git)
spark.install_pip_package("./pandas/")
# install packages from git repo
spark.install_pip_package("git+https://github.com/pandas-dev/pandas.git@main")
# use a pip cache directory to cache downloaded and built whl files
spark.install_pip_package("pandas", "pyarrow", "--cache-dir", "/home/user/.cache/pip")
# use an alternative index url (other than https://pypi.org/simple)
spark.install_pip_package("pandas", "pyarrow", "--index-url", "https://artifacts.company.com/pypi/simple")
# install pip packages quietly (only disables output of PIP)
spark.install_pip_package("pandas", "pyarrow", "--quiet")
Python projects can be installed from sources, including their dependencies, using Poetry:
# noinspection PyUnresolvedReferences
from gresearch.spark import *
spark.install_poetry_project("../my-poetry-project/", poetry_python="../venv-poetry/bin/python")
This example uses install_pip_package
in a Spark standalone cluster.
First checkout the example code:
git clone https://github.com/G-Research/spark-extension.git
cd spark-extension/examples/python-deps
Build a Docker image based on the official Spark release:
docker build -t spark-extension-example-docker .
Start the example Spark standalone cluster consisting of a Spark master and one worker:
docker compose -f docker-compose.yml up -d
Run the example.py
Spark application on the example cluster:
docker exec spark-master spark-submit --master spark://master:7077 --packages uk.co.gresearch.spark:spark-extension_2.12:2.11.0-3.5 /example/example.py
The --packages uk.co.gresearch.spark:spark-extension_2.12:2.11.0-3.5
argument
tells spark-submit
to add the spark-extension
Maven package to the Spark job.
Alternatively, install the pyspark-extension
PyPi package via pip install
and remove the --packages
argument from spark-submit
:
docker exec spark-master pip install --user pyspark_extension==2.11.1.3.5
docker exec spark-master spark-submit --master spark://master:7077 /example/example.py
This output proves that PySpark could call into the function func
, wich only works when Pandas and PyArrow are installed:
+---+
| id|
+---+
| 0|
| 1|
| 2|
+---+
Test that spark.install_pip_package("pandas", "pyarrow")
is really required by this example by removing this line from example.py
…
from pyspark.sql import SparkSession
def main():
spark = SparkSession.builder.appName("spark_app").getOrCreate()
def func(df):
return df
from gresearch.spark import install_pip_package
- spark.install_pip_package("pandas", "pyarrow")
spark.range(0, 3, 1, 5).mapInPandas(func, "id long").show()
if __name__ == "__main__":
main()
… and running the spark-submit
command again. The example does not work anymore,
because the Pandas and PyArrow packages are missing from the driver:
Traceback (most recent call last):
File "/opt/spark/python/lib/pyspark.zip/pyspark/sql/pandas/utils.py", line 27, in require_minimum_pandas_version
ModuleNotFoundError: No module named 'pandas'
Finally, shutdown the example cluster:
docker compose -f docker-compose.yml down