Why does spark-submit ignore the package that I include as part of the configuration of my spark session? - apache-spark

Question

I am trying to include the org.apache.spark:spark-sql-kafka-0-10_2.11:2.4.3 package as part of my spark code (via the SparkSession Builder). I understand that I can download the JAR myself and include it but I would like to figure out why the following is not working as expected:
from pyspark.sql import SparkSession
import pyspark
import json
if __name__ == "__main__":
spark = SparkSession.builder \
.master("local") \
.appName("App Name") \
.config("spark.jars.packages", "org.apache.spark:spark-sql-kafka-0-10_2.11:2.4.3") \
.getOrCreate()
df = spark \
.readStream \
.format("kafka") \
.option("kafka.bootstrap.servers", "localhost:9092") \
.option("subscribe", "first_topic") \
.load() \
.selectExpr("CAST(key AS STRING)", "CAST(value AS STRING)")
query = df \
.writeStream \
.format("console") \
.outputMode("update") \
.start()
When I run the job:
spark-submit main.py
I receive the following error:
py4j.protocol.Py4JJavaError: An error occurred while calling o48.load.
: org.apache.spark.sql.AnalysisException: Failed to find data source: kafka. Please deploy the application as per the deployment section of "Structured Streaming + Kafka Integration Guide".;
at org.apache.spark.sql.execution.datasources.DataSource$.lookupDataSource(DataSource.scala:652)
at org.apache.spark.sql.streaming.DataStreamReader.load(DataStreamReader.scala:161)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
at py4j.Gateway.invoke(Gateway.java:282)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:238)
at java.lang.Thread.run(Thread.java:748)
If I instead include the packages via the --packages flag, the dependencies are downloaded and the code runs as expected:
spark-submit --packages org.apache.spark:spark-sql-kafka-0-10_2.11:2.4.3 main.py
The code also works if I open the PySpark shell and paste the code above. Is there a reason that the spark-submit ignores the configuration?

Answer 1

I think that for configurations like "spark.jars.packages", these should be configured either in spark-defaults or passed by command-line arguments, setting it in the runtime shouldn't work.
Against better judgement
I remember some people claimed something like this worked for them, but I would say that the dependency is already somewhere there (installed in local repo), just loaded.
conf = pyspark.SparkConf()
conf.set("spark.jars.packages", "org.apache.spark:spark-sql-kafka-0-10_2.11:2.4.3")
spark = SparkSession.builder \
.master("local") \
.appName("App Name") \
.config(conf = conf) \
.getOrCreate()

Answer 2

When you run spark-submit, it already creates a SparkSession that is reused by your code - thus you have to provide everything through spark-submit.
However, you do not need to actually use spark-submit to run your Spark code. Assuming your main method looks like this:
def main():
spark = SparkSession.builder.config(...).getOrCreate()
# your spark code below
...
You can run this code just via python:
> python ./my_spark_script.py
This will run your program correctly

Answer 3

I faced same problem, after google I found that link
https://issues.apache.org/jira/browse/SPARK-21752
According to #srowen Sean R. Owen "At that point, your app has already launched. You can't change the driver classpath."