Zookeeper connection failing cp-rest-proxy with spotify kafka image

I have been using the kafka image provided by spotify to run kafka locally. I'm currently trying to use it with cp-kafka-rest and schema-registry images.

I need help resolving this issue:

ERROR (Log Group: kafka_rest_1_609fd108dcf4)

[main-SendThread(zookeeper:2181)] WARN org.apache.zookeeper.ClientCnxn - Session 0x0 for server zookeeper:2181, unexpected error, closing socket connection and attempting reconnect

java.nio.channels.UnresolvedAddressException 
  at sun.nio.ch.Net.checkAddress(Net.java:101)
  at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:622)
  at org.apache.zookeeper.ClientCnxnSocketNIO.registerAndConnect(ClientCnxnSocketNIO.java:277)
  at org.apache.zookeeper.ClientCnxnSocketNIO.connect(ClientCnxnSocketNIO.java:287)
  at org.apache.zookeeper.ClientCnxn$SendThread.startConnect(ClientCnxn.java:1021)
  at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1064)

Docker Compose

version: '3.5'
services:
  kafka:
    image: 'spotify/kafka'
    hostname: kafka
    environment:
      - ADVERTISED_HOST=kafka
      - ADVERTISED_PORT=9092
    ports:
      - "9092:9092"
      - "2181:2181"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    networks:
      - one
  kafka_rest:
    image: 'confluentinc/cp-kafka-rest:5.1.0'
    hostname: kafka_rest
    environment:
      - KAFKA_REST_ZOOKEEPER_CONNECT=zookeeper:2181
      - KAFKA_REST_LISTENERS=http://0.0.0.0:8082
      - KAFKA_REST_SCHEMA_REGISTRY_URL=http:schema-registry:8081
      - KAFKA_REST_HOST_NAME=kafka-rest
    networks:
      - one
  schema_registry:
    hostname: schema-registry
    image: 'confluentinc/cp-schema-registry:5.1.0'
    environment:
      - SCHEMA_REGISTRY_KAFKASTORE_CONNECTION_URL=zookeeper:2181
      - SCHEMA_REGISTRY_HOST_NAME=schema-registry
      - SCHEMA_REGISTRY_LISTENERS=http://0.0.0.0:8081
    networks:
      - one
networks:
  one:
    name: rest_network

You have no zookepeer container - it is actually your "kafka" service image that includes both Zookeeper and Kafka servers, so zookeeper:2181 should rather be kafka:2181

However, I would recommend not using the spotify images, as they are significantly outdated

You can find a fully functional Docker Compose example of the entire Confluent 5.1.0 Platform on Github

Here is the revelvant configuration you are looking for

---
version: '2'
services:
  zookeeper:
    image: confluentinc/cp-zookeeper:5.1.0
    hostname: zookeeper
    container_name: zookeeper
    ports:
      - "2181:2181"
    environment:
      ZOOKEEPER_CLIENT_PORT: 2181
      ZOOKEEPER_TICK_TIME: 2000

  broker:
    image: confluentinc/cp-enterprise-kafka:5.1.0
    hostname: broker
    container_name: broker
    depends_on:
      - zookeeper
    ports:
      - "9092:9092"
      - "29092:29092"
    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:9092,PLAINTEXT_HOST://localhost:29092
      KAFKA_METRIC_REPORTERS: io.confluent.metrics.reporter.ConfluentMetricsReporter
      KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1
      KAFKA_GROUP_INITIAL_REBALANCE_DELAY_MS: 0
      CONFLUENT_METRICS_REPORTER_BOOTSTRAP_SERVERS: broker:9092
      CONFLUENT_METRICS_REPORTER_ZOOKEEPER_CONNECT: zookeeper:2181
      CONFLUENT_METRICS_REPORTER_TOPIC_REPLICAS: 1
      CONFLUENT_METRICS_ENABLE: 'true'
      CONFLUENT_SUPPORT_CUSTOMER_ID: 'anonymous'

  schema-registry:
    image: confluentinc/cp-schema-registry:5.1.0
    hostname: schema-registry
    container_name: schema-registry
    depends_on:
      - zookeeper
      - broker
    ports:
      - "8081:8081"
    environment:
      SCHEMA_REGISTRY_HOST_NAME: schema-registry
      SCHEMA_REGISTRY_KAFKASTORE_CONNECTION_URL: 'zookeeper:2181'

  rest-proxy:
    image: confluentinc/cp-kafka-rest:5.1.0
    depends_on:
      - zookeeper
      - 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:9092'
      KAFKA_REST_LISTENERS: "http://0.0.0.0:8082"
      KAFKA_REST_SCHEMA_REGISTRY_URL: 'http://schema-registry:8081'