This project houses the experimental client for Spark Connect for Apache Spark written in Golang.
Currently, the Spark Connect client for Golang is highly experimental and should not be used in any production setting. In addition, the PMC of the Apache Spark project reserves the right to withdraw and abandon the development of this project if it is not sustainable.
git clone https://github.com/apache/spark-connect-go.git
git submodule update --init --recursive
make gen && make test
Ensure you have installed
buf CLI; more info
A very simple example in Go looks like following:
func main() {
remote := "localhost:15002"
spark, _ := sql.SparkSession.Builder.Remote(remote).Build()
defer spark.Stop()
df, _ := spark.Sql("select 'apple' as word, 123 as count union all select 'orange' as word, 456 as count")
df.Show(100, false)
}
Following diagram shows main code in current prototype:
+-------------------+
| |
| dataFrameImpl |
| |
+-------------------+
|
|
+
+-------------------+
| |
| sparkSessionImpl |
| |
+-------------------+
|
|
+
+---------------------------+ +----------------+
| | | |
| SparkConnectServiceClient |--------------+| Spark Driver |
| | | |
+---------------------------+ +----------------+
SparkConnectServiceClient is GRPC client which talks to Spark Driver. sparkSessionImpl generates dataFrameImpl
instances. dataFrameImpl uses the GRPC client in sparkSessionImpl to communicate with Spark Driver.
We will mimic the logic in Spark Connect Scala implementation, and adopt Go common practices, e.g. returning error object for
error handling.
-
Install Golang: https://go.dev/doc/install.
-
Download Spark distribution (3.4.0+), unzip the folder.
-
Start Spark Connect server by running command:
sbin/start-connect-server.sh --packages org.apache.spark:spark-connect_2.12:3.4.0
- In this repo, run Go application:
go run cmd/spark-connect-example-spark-session/main.go
Please review the Contribution to Spark guide for information on how to get started contributing to the project.