commit | 027327d94b3413ffb228ac482d51e75856c88d02 | [log] [tgz] |
---|---|---|
author | Niranjan Jayakar <nija@databricks.com> | Thu May 09 17:23:31 2024 +0900 |
committer | Hyukjin Kwon <gurwls223@apache.org> | Thu May 09 17:23:31 2024 +0900 |
tree | a52cd2f4626e1ee0247a0d0226718288d813b88c | |
parent | 34ee0d8414b2f919a5f40e4e4b1ab4cfd033b696 [diff] |
[SPARK-47986][CONNECT][PYTHON] Unable to create a new session when the default session is closed by the server ### What changes were proposed in this pull request? This is a follow-up to a previous improvement - 7d04d0f0. In some cases, particularly when running older versions of the Spark cluster (3.5), the error actually manifests as a mismatch in the observed server-side session id between calls. With this fix, we also capture this case and ensure that this case is also handled. Further, we improve the implementation of `getActiveSession()` and introduce a similar `getDefaultSession()` that accounts for stopped sessions. This ensures that all places where default or active session is used, stopped sessions are considered neither default nor active. ### Why are the changes needed? Explained above. ### Does this PR introduce _any_ user-facing change? Previously, when client encounters a session mismatch, a user cannot create a new session. With this change, a user can call `getOrCreate()` on the SparkSession builder and create a new session. ### How was this patch tested? Attached unit tests. ### Was this patch authored or co-authored using generative AI tooling? No. Closes #46435 from nija-at/session-expires-part2. Lead-authored-by: Niranjan Jayakar <nija@databricks.com> Co-authored-by: Hyukjin Kwon <gurwls223@gmail.com> Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
Spark is a unified analytics engine for large-scale data processing. It provides high-level APIs in Scala, Java, Python, and R, and an optimized engine that supports general computation graphs for data analysis. It also supports a rich set of higher-level tools including Spark SQL for SQL and DataFrames, pandas API on Spark for pandas workloads, MLlib for machine learning, GraphX for graph processing, and Structured Streaming for stream processing.
You can find the latest Spark documentation, including a programming guide, on the project web page. This README file only contains basic setup instructions.
Spark is built using Apache Maven. To build Spark and its example programs, run:
./build/mvn -DskipTests clean package
(You do not need to do this if you downloaded a pre-built package.)
More detailed documentation is available from the project site, at “Building Spark”.
For general development tips, including info on developing Spark using an IDE, see “Useful Developer Tools”.
The easiest way to start using Spark is through the Scala shell:
./bin/spark-shell
Try the following command, which should return 1,000,000,000:
scala> spark.range(1000 * 1000 * 1000).count()
Alternatively, if you prefer Python, you can use the Python shell:
./bin/pyspark
And run the following command, which should also return 1,000,000,000:
>>> spark.range(1000 * 1000 * 1000).count()
Spark also comes with several sample programs in the examples
directory. To run one of them, use ./bin/run-example <class> [params]
. For example:
./bin/run-example SparkPi
will run the Pi example locally.
You can set the MASTER environment variable when running examples to submit examples to a cluster. This can be spark:// URL, “yarn” to run on YARN, and “local” to run locally with one thread, or “local[N]” to run locally with N threads. You can also use an abbreviated class name if the class is in the examples
package. For instance:
MASTER=spark://host:7077 ./bin/run-example SparkPi
Many of the example programs print usage help if no params are given.
Testing first requires building Spark. Once Spark is built, tests can be run using:
./dev/run-tests
Please see the guidance on how to run tests for a module, or individual tests.
There is also a Kubernetes integration test, see resource-managers/kubernetes/integration-tests/README.md
Spark uses the Hadoop core library to talk to HDFS and other Hadoop-supported storage systems. Because the protocols have changed in different versions of Hadoop, you must build Spark against the same version that your cluster runs.
Please refer to the build documentation at “Specifying the Hadoop Version and Enabling YARN” for detailed guidance on building for a particular distribution of Hadoop, including building for particular Hive and Hive Thriftserver distributions.
Please refer to the Configuration Guide in the online documentation for an overview on how to configure Spark.
Please review the Contribution to Spark guide for information on how to get started contributing to the project.