Connect PySpark to Kafka from Docker container - docker

Question

I have a Kafka cluster that I'm managing with Docker.
I have a container where I'm running the broker and another one where I run the pyspark program which is supposed to connect to the kafka topic inside the broker container.
If I run the pyspark script in my local laptop everything runs perfectly but if I try to run the same code from inside the pyspark container I get the following error:
AnalysisException: Failed to find data source: kafka. Please deploy the application as per the deployment section of "Structured Streaming + Kafka Integration Guide"
Does anybody know how can I access the Kafka topic running in a docker container from another external container?
This is the PySpark code
df = spark \
.readStream \
.format("kafka") \
.option("kafka.bootstrap.servers", "localhost:9092") \
.option("failOnDataLoss", "false") \
.option("subscribe", "tweets") \
.option("startingOffsets", "earliest") \
.load()
This is my docker-compose.yml
version: "2"
services:
zookeeper:
image: confluentinc/cp-zookeeper:6.1.0
hostname: zookeeper
container_name: zookeeper
ports:
- "2181:2181"
environment:
ZOOKEEPER_CLIENT_PORT: 2181
ZOOKEEPER_TICK_TIME: 2000
broker:
image: confluentinc/cp-server:6.1.0
hostname: broker
container_name: broker
depends_on:
- zookeeper
ports:
- "9092:9092"
- "9101:9101"
environment:
KAFKA_BROKER_ID: 1
KAFKA_ZOOKEEPER_CONNECT: "zookeeper:2181"
KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,PLAINTEXT_HOST:PLAINTEXT
KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://broker:29092,PLAINTEXT_HOST://localhost:9092
KAFKA_METRIC_REPORTERS: io.confluent.metrics.reporter.ConfluentMetricsReporter
KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1
KAFKA_GROUP_INITIAL_REBALANCE_DELAY_MS: 0
KAFKA_CONFLUENT_LICENSE_TOPIC_REPLICATION_FACTOR: 1
KAFKA_CONFLUENT_BALANCER_TOPIC_REPLICATION_FACTOR: 1
KAFKA_TRANSACTION_STATE_LOG_MIN_ISR: 1
KAFKA_TRANSACTION_STATE_LOG_REPLICATION_FACTOR: 1
KAFKA_JMX_PORT: 9101
KAFKA_JMX_HOSTNAME: localhost
KAFKA_CONFLUENT_SCHEMA_REGISTRY_URL: http://schema-registry:8081
CONFLUENT_METRICS_REPORTER_BOOTSTRAP_SERVERS: broker:29092
CONFLUENT_METRICS_REPORTER_TOPIC_REPLICAS: 1
CONFLUENT_METRICS_ENABLE: "true"
CONFLUENT_SUPPORT_CUSTOMER_ID: "anonymous"
schema-registry:
image: confluentinc/cp-schema-registry:6.1.0
hostname: schema-registry
container_name: schema-registry
depends_on:
- broker
ports:
- "8081:8081"
environment:
SCHEMA_REGISTRY_HOST_NAME: schema-registry
SCHEMA_REGISTRY_KAFKASTORE_BOOTSTRAP_SERVERS: "broker:29092"
SCHEMA_REGISTRY_LISTENERS: http://0.0.0.0:8081
connect:
image: cnfldemos/cp-server-connect-datagen:latest
hostname: connect
container_name: connect
build:
context: .
dockerfile: Dockerfile_connect
depends_on:
- broker
- schema-registry
ports:
- "8083:8083"
environment:
CONNECT_BOOTSTRAP_SERVERS: "broker:29092"
CONNECT_REST_ADVERTISED_HOST_NAME: connect
CONNECT_REST_PORT: 8083
CONNECT_GROUP_ID: compose-connect-group
CONNECT_CONFIG_STORAGE_TOPIC: docker-connect-configs
CONNECT_CONFIG_STORAGE_REPLICATION_FACTOR: 1
CONNECT_OFFSET_FLUSH_INTERVAL_MS: 10000
CONNECT_OFFSET_STORAGE_TOPIC: docker-connect-offsets
CONNECT_OFFSET_STORAGE_REPLICATION_FACTOR: 1
CONNECT_STATUS_STORAGE_TOPIC: docker-connect-status
CONNECT_STATUS_STORAGE_REPLICATION_FACTOR: 1
CONNECT_KEY_CONVERTER: org.apache.kafka.connect.storage.StringConverter
CONNECT_VALUE_CONVERTER: io.confluent.connect.avro.AvroConverter
CONNECT_VALUE_CONVERTER_SCHEMA_REGISTRY_URL: http://schema-registry:8081
# CLASSPATH required due to CC-2422
CLASSPATH: /usr/share/java/monitoring-interceptors/monitoring-interceptors-6.1.0.jar
CONNECT_PRODUCER_INTERCEPTOR_CLASSES: "io.confluent.monitoring.clients.interceptor.MonitoringProducerInterceptor"
CONNECT_CONSUMER_INTERCEPTOR_CLASSES: "io.confluent.monitoring.clients.interceptor.MonitoringConsumerInterceptor"
CONNECT_PLUGIN_PATH: "/usr/share/java,/usr/share/confluent-hub-components"
CONNECT_LOG4J_LOGGERS: org.apache.zookeeper=ERROR,org.I0Itec.zkclient=ERROR,org.reflections=ERROR
control-center:
image: confluentinc/cp-enterprise-control-center:6.1.0
hostname: control-center
container_name: control-center
depends_on:
- broker
- schema-registry
- connect
- ksqldb-server
ports:
- "9021:9021"
environment:
CONTROL_CENTER_BOOTSTRAP_SERVERS: "broker:29092"
CONTROL_CENTER_CONNECT_CLUSTER: "connect:8083"
CONTROL_CENTER_KSQL_KSQLDB1_URL: "http://ksqldb-server:8088"
CONTROL_CENTER_KSQL_KSQLDB1_ADVERTISED_URL: "http://localhost:8088"
CONTROL_CENTER_SCHEMA_REGISTRY_URL: "http://schema-registry:8081"
CONTROL_CENTER_REPLICATION_FACTOR: 1
CONTROL_CENTER_INTERNAL_TOPICS_PARTITIONS: 1
CONTROL_CENTER_MONITORING_INTERCEPTOR_TOPIC_PARTITIONS: 1
CONFLUENT_METRICS_TOPIC_REPLICATION: 1
PORT: 9021
ksqldb-server:
image: confluentinc/cp-ksqldb-server:6.1.0
hostname: ksqldb-server
container_name: ksqldb-server
depends_on:
- broker
- connect
ports:
- "8088:8088"
environment:
KSQL_CONFIG_DIR: "/etc/ksql"
KSQL_BOOTSTRAP_SERVERS: "broker:29092"
KSQL_HOST_NAME: ksqldb-server
KSQL_LISTENERS: "http://0.0.0.0:8088"
KSQL_CACHE_MAX_BYTES_BUFFERING: 0
KSQL_KSQL_SCHEMA_REGISTRY_URL: "http://schema-registry:8081"
KSQL_PRODUCER_INTERCEPTOR_CLASSES: "io.confluent.monitoring.clients.interceptor.MonitoringProducerInterceptor"
KSQL_CONSUMER_INTERCEPTOR_CLASSES: "io.confluent.monitoring.clients.interceptor.MonitoringConsumerInterceptor"
KSQL_KSQL_CONNECT_URL: "http://connect:8083"
KSQL_KSQL_LOGGING_PROCESSING_TOPIC_REPLICATION_FACTOR: 1
KSQL_KSQL_LOGGING_PROCESSING_TOPIC_AUTO_CREATE: "true"
KSQL_KSQL_LOGGING_PROCESSING_STREAM_AUTO_CREATE: "true"
ksqldb-cli:
image: confluentinc/cp-ksqldb-cli:6.1.0
container_name: ksqldb-cli
depends_on:
- broker
- connect
- ksqldb-server
entrypoint: /bin/sh
tty: true
ksql-datagen:
image: confluentinc/ksqldb-examples:6.1.0
hostname: ksql-datagen
container_name: ksql-datagen
depends_on:
- ksqldb-server
- broker
- schema-registry
- connect
command: "bash -c 'echo Waiting for Kafka to be ready... && \
cub kafka-ready -b broker:29092 1 40 && \
echo Waiting for Confluent Schema Registry to be ready... && \
cub sr-ready schema-registry 8081 40 && \
echo Waiting a few seconds for topic creation to finish... && \
sleep 11 && \
tail -f /dev/null'"
environment:
KSQL_CONFIG_DIR: "/etc/ksql"
STREAMS_BOOTSTRAP_SERVERS: broker:29092
STREAMS_SCHEMA_REGISTRY_HOST: schema-registry
STREAMS_SCHEMA_REGISTRY_PORT: 8081
rest-proxy:
image: confluentinc/cp-kafka-rest:6.1.0
depends_on:
- broker
- schema-registry
ports:
- 8082:8082
hostname: rest-proxy
container_name: rest-proxy
environment:
KAFKA_REST_HOST_NAME: rest-proxy
KAFKA_REST_BOOTSTRAP_SERVERS: "broker:29092"
KAFKA_REST_LISTENERS: "http://0.0.0.0:8082"
KAFKA_REST_SCHEMA_REGISTRY_URL: "http://schema-registry:8081"
elasticsearch:
image: docker.elastic.co/elasticsearch/elasticsearch:7.11.2
container_name: elasticsearch
environment:
- xpack.security.enabled=false
- discovery.type=single-node
ulimits:
memlock:
soft: -1
hard: -1
nofile:
soft: 65536
hard: 65536
cap_add:
- IPC_LOCK
volumes:
- elasticsearch-data:/usr/share/elasticsearch/data
ports:
- 9200:9200
- 9300:9300
kibana:
container_name: kibana
image: docker.elastic.co/kibana/kibana:7.11.2
environment:
- ELASTICSEARCH_HOSTS=http://elasticsearch:9200
ports:
- 5601:5601
depends_on:
- elasticsearch
pyspark:
image: jupyter/pyspark-notebook:latest
hostname: pyspark
container_name: pyspark
ports:
- 8888:8888
#volumes:
# - pySpark: pySpark/
depends_on:
- broker
volumes:
elasticsearch-data:
driver: local
pySpark:
driver: local

Answer 1

There are several problems in your setup:
You don't add the package for Kafka support as described in docs. It's either needs to be added when starting pyspark, or when initializing session, something like this (change 3.0.1 to version that is used in your jupyter container):
SparkSession.builder.appName('my_app')\
.config('spark.jars.packages', 'org.apache.spark:spark-sql-kafka-0-10_2.12:3.0.1')\
.getOrCreate()
you're connecting to "localhost:9092", but it's incorrect inside the container because container with Jupyter has its own localhost that is different from Kafka container's localhost. You need to use name broker instead, as it's declared in the docker-compose.yaml