Kafdrop is a UI for monitoring Apache Kafka clusters. The tool displays information such as brokers, topics, partitions, and even lets you view messages. It is a light weight application that runs on Spring Boot and requires very little configuration.
- Java 8
- Kafka 2.0 or later (might work with earlier versions)
- Zookeeper (3.4.5 or later)
Optional, additional integration:
- Schema Registry
After cloning the repository, building should just be a matter of running a standard Maven build:
$ mvn clean package
The build process creates an executable JAR file.
java -jar ./target/kafdrop-<version>.jar --zookeeper.connect=<host:port>,<host:port>,... --kafka.brokers=<host:port>,<host:port>,...
Then open a browser and navigate to http://localhost:9000. The port can be overridden by adding the following config:
--server.port=<port>
Additionally, you can optionally configure a schema registry connection with:
--schemaregistry.connect=http://localhost:8081
Finally, a default message format (e.g. to deserialize Avro messages) can optionally be configured as follows:
--message.format=AVRO
Valid format values are "DEFAULT" and "AVRO". This setting can also be configured at the topic level via dropdown when viewing messages.
Note for Mac Users: You need to convert newline formatting of the kafdrop.sh file before running this command:
dos2unix src/main/docker/*
The following maven command will generate a Docker image:
mvn clean package assembly:single docker:build
Once the build finishes you can launch the image as follows:
docker run -d -p 9000:9000 -e ZOOKEEPER_CONNECT=<host:port,host:port> kafdrop
And access the UI at http://localhost:9000.
| Option | Default | Description |
|---|---|---|
| kafka.truststoreLocation | Location of the truststore used for secure connections | |
| kafka.keystoreLocation | Location of the keystore used for secure connections | |
| kafka.additionalProperties. | Additional properties to pass to the Admin or Consumer clients | |
| kafka.adminPool.minIdle | 0 | Minimum number of unused admin clients to keep open |
| kafka.adminPool.maxIdle | 8 | Maximum number of unused admin clients to keep open |
| kafka.adminPool.maxTotal | 8 | Maximum number of admin clients to have open at one time |
| kafka.adminPool.maxWaitMillis | -1 | Milliseconds to wait for an admin client from the pool (-1 == forever) |
| kafka.consumerPool.minIdle | 0 | Minimum number of unused consumer clients to keep open |
| kafka.consumerPool.maxIdle | 8 | Maximum number of unused consumer clients to keep open |
| kafka.consumerPool.maxTotal | 8 | Maximum number of consumer clients to have open at one time |
| kafka.consumerPool.maxWaitMillis | -1 | Millis to wait for a consumer client from the pool (-1 == forever) |
Starting with version 2.0.0, Kafdrop offers a set of Kafka APIs that mirror the existing HTML views. Any existing endpoint can be returned as JSON by simply setting the Accept : application/json header. There are also two endpoints that are JSON only:
/topic : Returns array of all topic names
/topic/{topicName}/{consumerId} : Return partition offset and lag details for a specific topic and consumer.
To help document the Kafka APIs, Swagger has been included. The Swagger output is available by default at the following Kafdrop URL:
/v2/api-docs
However this can be overridden with the following configuration:
springfox.documentation.swagger.v2.path=/new/swagger/path
Currently only the JSON endpoints are included in the Swagger output; the HTML views and Spring Boot debug endpoints are excluded.
You can disable Swagger output with the following configuration:
swagger.enabled=false
Starting in version 2.0.0, Kafdrop sets CORS headers for all endpoints. You can control the CORS header values with the following configurations:
cors.allowOrigins (default is *)
cors.allowMethods (default is GET,POST,PUT,DELETE)
cors.maxAge (default is 3600)
cors.allowCredentials (default is true)
cors.allowHeaders (default is Origin,Accept,X-Requested-With,Content-Type,Access-Control-Request-Method,Access-Control-Request-Headers,Authorization)
You can also disable CORS entirely with the following configuration:
cors.enabled=false