fast-data-dev / kafka-lenses-dev (Lenses Box)

lensesio/fast-data-dev

lensesio/box (lensesio/box)

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Apache Kafka docker image for developers; with Lenses (lensesio/box) or Lenses.io's open source UI tools (lensesio/fast-data-dev). Have a full fledged Kafka installation up and running in seconds and top it off with a modern streaming platform (only for kafka-lenses-dev), intuitive UIs and extra goodies. Also includes Kafka Connect, Schema Registry, Lenses.io's Stream Reactor 25+ Connectors and more.

View latest demo on-line or get a free license for Lenses Box

Introduction

When you need:

1. A Kafka distribution with Apache Kafka, Kafka Connect, Zookeeper, Confluent Schema Registry and REST Proxy
2. Lenses.io Lenses or kafka-topics-ui, schema-registry-ui, kafka-connect-ui
3. Lenses.io Stream Reactor, 25+ Kafka Connectors to simplify ETL processes
4. Integration testing and examples embedded into the docker

just run:

docker run --rm --net=host lensesio/fast-data-dev

That's it. Visit http://localhost:3030 to get into the fast-data-dev environment

All the service ports are exposed, and can be used from localhost / or within your IntelliJ. The kafka broker is exposed by default at port 9092, zookeeper at port 2181, schema registry at 8081, connect at 8083. As an example, to access the JMX data of the broker run:

jconsole localhost:9581

If you want to have the services remotely accessible, then you may need to pass in your machine's IP address or hostname that other machines can use to access it:

docker run --rm --net=host -e ADV_HOST=<IP> lensesio/fast-data-dev

Hit control+c to stop and remove everything

Mac and Windows users (docker-machine)

Create a VM with 4+GB RAM using Docker Machine:

docker-machine create --driver virtualbox --virtualbox-memory 4096 lensesio

Run docker-machine ls to verify that the Docker Machine is running correctly. The command's output should be similar to:

$ docker-machine ls
NAME        ACTIVE   DRIVER       STATE     URL                         SWARM   DOCKER        ERRORS
lensesio     *        virtualbox   Running   tcp://192.168.99.100:2376           v17.03.1-ce

Configure your terminal to be able to use the new Docker Machine named lensesio:

eval $(docker-machine env lensesio)

And run the Kafka Development Environment. Define ports, advertise the hostname and use extra parameters:

docker run --rm -p 2181:2181 -p 3030:3030 -p 8081-8083:8081-8083 \
       -p 9581-9585:9581-9585 -p 9092:9092 -e ADV_HOST=192.168.99.100 \
       lensesio/fast-data-dev:latest

That's it. Visit http://192.168.99.100:3030 to get into the fast-data-dev environment

Run on the Cloud

You may want to quickly run a Kafka instance in GCE or AWS and access it from your local computer. Fast-data-dev has you covered.

Start a VM in the respective cloud. You can use the OS of your choice, provided it has a docker package. CoreOS is a nice choice as you get docker out of the box.

Next you have to open the firewall, both for your machines but also for the VM itself. This is important!

Once the firewall is open try:

docker run -d --net=host -e ADV_HOST=[VM_EXTERNAL_IP] \
           -e RUNNING_SAMPLEDATA=1 lensesio/fast-data-dev

Alternatively just export the ports you need. E.g:

docker run -d -p 2181:2181 -p 3030:3030 -p 8081-8083:8081-8083 \
           -p 9581-9585:9581-9585 -p 9092:9092 -e ADV_HOST=[VM_EXTERNAL_IP] \
           -e RUNNING_SAMPLEDATA=1 lensesio/fast-data-dev

Enjoy Kafka, Schema Registry, Connect, Lensesio UIs and Stream Reactor.

Customize execution

Fast-data-dev and kafka-lenses-dev support custom configuration and extra features via environment variables.

fast-data-dev / kafka-lenses-dev advanced configuration

*Available connectors are: azure-documentdb, blockchain, bloomberg, cassandra, coap, druid, elastic, elastic5, ftp, hazelcast, hbase, influxdb, jms, kudu, mongodb, mqtt, pulsar, redis, rethink, voltdb, couchbase, dbvisitreplicate, debezium-mongodb, debezium-mysql, debezium-postgres, elasticsearch, hdfs, jdbc, s3, twitter.

To programmatically get a list, run:

docker run --rm -it lensesio/fast-data-dev \
       find /opt/landoop/connectors -type d -maxdepth 2 -name "kafka-connect-*"

Configure Kafka Components

You may configure any Kafka component (broker, schema registry, connect, rest proxy) by converting the configuration option to uppercase, replace dots with underscores and prepend with <SERVICE>_.

As example:

• To set the log.retention.bytes for the broker, you would set the environment variable KAFKA_LOG_RETENTION_BYTES=1073741824.
• To set the kafkastore.topic for the schema registry, you would set SCHEMA_REGISTRY_KAFKASTORE_TOPIC=_schemas.
• To set the plugin.path for the connect worker, you would set CONNECT_PLUGIN_PATH=/var/run/connect/connectors/stream-reactor,/var/run/connect/connectors/third-party,/connectors.
• To set the schema.registry.url for the rest proxy, you would set KAFKA_REST_SCHEMA_REGISTRY_URL=http://localhost:8081.

We also support the variables that set JVM options, such as KAFKA_OPTS, SCHEMA_REGISTRY_JMX_OPTS, etc.

Lensesio's Kafka Distribution (LKD) supports a few extra flags as well. Since in the Apache Kafka build, both the broker and the connect worker expect JVM options at the default KAFKA_OPTS, LKD supports using BROKER_OPTS, etc for the broker and CONNECT_OPTS, etc for the connect worker. Of course KAFKA_OPTS are still supported and apply to both applications (and the embedded zookeeper).

Another LKD addition are the VANILLA_CONNECT, SERDE_TOOLS and LANDOOP_COMMON flags for Kafka Connect. By default we load into the Connect Classpath the Schema Registry and Serde Tools by Confluent in order to support avro and our own base jars in order to support avro and our connectors. You can choose to run a completely vanilla kafka connect, the same that comes from the official distribution, without avro support by setting VANILLA_CONNECT=1. Please note that most if not all the connectors will fail to load, so it would be wise to disable them. SERDE_TOOLS=0 will disable Confluent's jars and LANDOOP_COMMON=0 will disable our jars. Any of these is enough to support avro, but disabling LANDOOP_COMMON will render Stream Reactor inoperable.

Versions

The latest version of this docker image tracks our latest stable tag (1.0.1). Our images include:

*LKD stands for Lenses.io's Kafka Distribution. We build and package Apache Kafka with Kafka Connect and Apache Zookeeper, Confluent Schema Registry and REST Proxy and a collection of third party Kafka Connectors as well as our own Stream Reactor collection.

Please note the BSL license of the tools. To use them on a PROD cluster with > 3 Kafka nodes, you should contact us.

Building it

Fast-data-dev and Lenses Box require a recent version of docker which supports multistage builds. Optionally you should also enable the buildx plugin to enable multi-arch builds, even if you just use the default builder.

To build it just run:

docker build -t lensesio-local/fast-data-dev .

Periodically pull from docker hub to refresh your cache.

If your docker version does not support multi-arch builds, or you don't have the buildx plugin installed, use the build args demonstrated below to emulate multi-arch support:

docker build --build-arg TARGETOS=linux --build-arg TARGETARCH=amd64 -t lensesio-local/fast-data-dev .

Advanced Features and Settings

Custom Ports

To use custom ports for the various services, you can take advantage of the ZK_PORT, BROKER_PORT, REGISTRY_PORT, REST_PORT, CONNECT_PORT and WEB_PORT environment variables. One catch is that you can't swap ports; e.g to assign 8082 (default REST Proxy port) to the brokers.

docker run --rm -it \
           -p 3181:3181 -p 3040:3040 -p 7081:7081 \
           -p 7082:7082 -p 7083:7083 -p 7092:7092 \
           -e ZK_PORT=3181 -e WEB_PORT=3040 -e REGISTRY_PORT=8081 \
           -e REST_PORT=7082 -e CONNECT_PORT=7083 -e BROKER_PORT=7092 \
           -e ADV_HOST=127.0.0.1 \
           lensesio/fast-data-dev

A port of 0 will disable the service.

Execute kafka command line tools

Do you need to execute kafka related console tools? Whilst your Kafka containers is running, try something like:

docker run --rm -it --net=host lensesio/fast-data-dev kafka-topics --zookeeper localhost:2181 --list

Or enter the container to use any tool as you like:

docker run --rm -it --net=host lensesio/fast-data-dev bash

View logs

You can view the logs from the web interface. If you prefer the command line, every application stores its logs under /var/log inside the container. If you have your container's ID, or name, you could do something like:

docker exec -it <ID> cat /var/log/broker.log

Enable SSL on Broker

Do you want to test your application over an authenticated TLS connection to the broker? We got you covered. Enable TLS via -e ENABLE_SSL=1:

docker run --rm --net=host \
           -e ENABLE_SSL=1 \
           lensesio/fast-data-dev

When fast-data-dev spawns, it will create a self-signed CA. From that it will create a truststore and two signed key-certificate pairs, one for the broker, one for your client. You can access the truststore and the client's keystore from our Web UI, under /certs (e.g http://localhost:3030/certs). The password for both the keystores and the TLS key is fastdata. The SSL port of the broker is 9093, configurable via the BROKER_SSL_PORT variable.

Here is a simple example of how the SSL functionality can be used. Let's spawn a fast-data-dev to act as the server:

docker run --rm --net=host -e ENABLE_SSL=1 -e RUNTESTS=0 lensesio/fast-data-dev

On a new console, run another instance of fast-data-dev only to get access to Kafka command line utilities and use TLS to connect to the broker of the former container:

docker run --rm -it --net=host --entrypoint bash lensesio/fast-data-dev
root@fast-data-dev / $ wget localhost:3030/certs/truststore.jks
root@fast-data-dev / $ wget localhost:3030/certs/client.jks
root@fast-data-dev / $ kafka-producer-perf-test --topic tls_test \
  --throughput 100000 --record-size 1000 --num-records 2000 \
  --producer-props bootstrap.servers="localhost:9093" security.protocol=SSL \
  ssl.keystore.location=client.jks ssl.keystore.password=fastdata \
  ssl.key.password=fastdata ssl.truststore.location=truststore.jks \
  ssl.truststore.password=fastdata

Since the plaintext port is also available, you can test both and find out which is faster and by how much. ;)

Advanced Connector settings

Explicitly Enable Connectors

The number of connectors present significantly affects Kafka Connect's startup time, as well as its memory usage. You can enable connectors explicitly using the CONNECTORS environment variable:

docker run --rm -it --net=host \
           -e CONNECTORS=jdbc,elastic,hbase \
           lensesio/fast-data-dev

Please note that if you don't enable jdbc, some tests will fail. This doesn't affect fast-data-dev's operation.

Explicitly Disable Connectors

Following the same logic as in the paragraph above, you can instead choose to explicitly disable certain connectors using the DISABLE environment variable. It takes a comma separated list of connector names you want to disable:

docker run --rm -it --net=host \
           -e DISABLE=elastic,hbase \
           lensesio/fast-data-dev

If you disable the jdbc connector, some tests will fail to run.

Enable additional connectors

If you have a custom connector you would like to use, you can mount it at folder /connectors. plugin.path variable for Kafka Connect is set up to include /connectors/, so it will use any single-jar connectors it will find inside this directory and any multi-jar connectors it will find in subdirectories of this directory.

docker run --rm -it --net=host \
           -v /path/to/my/connector/connector.jar:/connectors/connector.jar \
           -v /path/to/my/multijar-connector-directory:/connectors/multijar-connector-directory \
           lensesio/fast-data-dev

Build Kafka-Connect clusters

Note: This feature is deprecated.

If you already have your Kafka brokers and ZKs infrastructure in place and you need to spin up a few Kafka-Connect clusters, check the fast-data-connect-cluster, a spinoff of fast-data-dev aimed at running many connect clusters concurrently.

In short, you can run a docker Kafka-Connect instance to join the connect-cluster with ID = 01 with:

docker run -d --net=host \
           -e ID=01 \
           -e BS=broker1:9092,broker2:9092 \
           -e ZK=zk1:2181,zk2:2181 \
           -e SC=http://schema-registry:8081 \
           -e HOST=<IP OR FQDN>
           lensesio/fast-data-dev-connect-cluster

FAQ

• Lensesio's Fast Data Web UI tools and integration test requires some time till they fully work. Especially the tests and Kafka Connect UI will need a few minutes.

  That is because the services (Kafka, Schema Registry, Kafka Connect, REST Proxy) have to start and initialize before the UIs can read data.

• What resources does this container need?

  An idle, fresh container will need about 3GiB of RAM. As at least 5 JVM applications will be working in it, your mileage will vary. In our experience Kafka Connect usually requires a lot of memory. It's heap size is set by default to 640MiB but you'll might need more than that.

• Fast-data-dev does not start properly, broker fails with:

  [2016-08-23 15:54:36,772] FATAL [Kafka Server 0], Fatal error during KafkaServer startup. Prepare to shutdown (kafka.server.KafkaServer) java.net.UnknownHostException: [HOSTNAME]: [HOSTNAME]: unknown error

  JVM based apps tend to be a bit sensitive to hostname issues. Either run the image without --net=host and expose all ports (2181, 3030, 8081, 8082, 8083, 9092) to the same port at the host, or better yet make sure your hostname resolve to the localhost address (127.0.0.1). Usually to achieve this, you need to add your hostname (case sensitive) at /etc/hosts as the first name after 127.0.0.1. E.g:

  127.0.0.1 MyHost localhost
  

Detailed configuration options

Web Only Mode

Note: Web only mode will be deprecated in the future.

This is a special mode only for Linux hosts, where only Lensesio's Web UIs are started and kafka services are expected to be running on the local machine. It must be run with --net=host flag, thus the Linux only requisite:

docker run --rm -it --net=host \
           -e WEB_ONLY=true \
           lensesio/fast-data-dev

This is useful if you already have a Kafka cluster and want just the additional Lensesio Fast Data web UI. Please note that we provide separate, lightweight docker images for each UI component and we strongly encourage to use these over fast-data-dev.

Connect Heap Size

You can configure Connect's heap size via the environment variable CONNECT_HEAP. The default is 640M:

docker run -e CONNECT_HEAP=3G -d lensesio/fast-data-dev

Basic Auth (password)

We have included a web server to serve Lensesio UIs and proxy the schema registry and kafa REST proxy services, in order to share your docker over the web. If you want some basic protection, pass the PASSWORD variable and the web server will be protected by user kafka with your password. If you want to setup the username too, set the USER variable.

 docker run --rm -it -p 3030:3030 \
            -e PASSWORD=password \
            lensesio/fast-data-dev

Disable tests

By default this docker runs a set of coyote tests, to ensure that your container and development environment is all set up. You can disable running the coyote tests using the flag:

-e RUNTESTS=0

Run Kafka as root

In the recent versions of fast-data-dev, we switched to running Kafka as user nobody instead of root since it was a bad practice. The old behaviour may still be desirable, for example on our HDFS connector tests, Connect worker needs to run as the root user in order to be able to write to the HDFS. To switch to the old behaviour, use:

-e RUN_AS_ROOT=1

JMX Metrics

JMX metrics are enabled by default. If you want to disable them for some reason (e.g you need the ports for other purposes), use the DISABLE_JMX environment variable:

docker run --rm -it --net=host \
           -e DISABLE_JMX=1 \
           lensesio/fast-data-dev

JMX ports are hardcoded to 9581 for the broker, 9582 for schema registry, 9583 for REST proxy and 9584 for connect distributed. Zookeeper is exposed at 9585.