[SPARK-40993][CONNECT][PYTHON][DOCS] Migrate markdown style README to PySpark Development Documentation

python/docs/source/development/testing.rst

@@ -55,3 +55,74 @@ Running tests using GitHub Actions
 You can run the full PySpark tests by using GitHub Actions in your own forked GitHub
 repository with a few clicks. Please refer to
 `Running tests in your forked repository using GitHub Actions <https://spark.apache.org/developer-tools.html>`_ for more details.
+
+
+===================================
+Testing Spark Connect Python Client
+===================================
+
+**Spark Connect is a strictly experimental feature and under heavy development.
+All APIs should be considered volatile and should not be used in production.**
+
+This module contains the implementation of Spark Connect which is a logical plan
+facade for the implementation in Spark. Spark Connect is directly integrated into the build
+of Spark. To enable it, you only need to activate the driver plugin for Spark Connect.
+
+
+Build
+-----
+
+.. code-block:: bash
+
+    ./build/mvn -Phive clean package
+
+or
+
+.. code-block:: bash
+
+    ./build/sbt -Phive clean package
+
+
+Run Spark Shell
+---------------
+
+To run Spark Connect you locally built:
+
+.. code-block:: bash
+
+    # Scala shell
+    ./bin/spark-shell \
+    --jars `ls connector/connect/target/**/spark-connect*SNAPSHOT.jar | paste -sd ',' -` \
+    --conf spark.plugins=org.apache.spark.sql.connect.SparkConnectPlugin
+
+.. code-block:: bash
+
+    # PySpark shell
+    ./bin/pyspark \
+    --jars `ls connector/connect/target/**/spark-connect*SNAPSHOT.jar | paste -sd ',' -` \
+    --conf spark.plugins=org.apache.spark.sql.connect.SparkConnectPlugin
+
+To use the release version of Spark Connect:
+
+.. code-block:: bash
+
+    ./bin/spark-shell \
+    --packages org.apache.spark:spark-connect_2.12:3.4.0 \
+    --conf spark.plugins=org.apache.spark.sql.connect.SparkConnectPlugin
+
+
+Run Tests
+---------
+
+.. code-block:: bash
+
+    ./python/run-tests --testnames 'pyspark.sql.tests.connect.test_connect_basic'
+
+
+Generate proto generated files for the Python client
+----------------------------------------------------
+
+1. Install `buf version 1.8.0`: https://docs.buf.build/installation
+2. Run `pip install grpcio==1.48.1 protobuf==4.21.6 mypy-protobuf==3.3.0`
+3. Run `./connector/connect/dev/generate_protos.sh`
+4. Optional Check `./dev/check-codegen-python.py`