API examples

These examples assume the Schema Registry is reachable at http://localhost:8081 and the REST proxy at http://localhost:8082. Adjust the hosts to match your deployment.

Schema Registry

Register the first version of a schema under the subject test-key using an Avro schema:

curl -X POST -H "Content-Type: application/vnd.schemaregistry.v1+json" \
  --data '{"schema": "{\"type\": \"record\", \"name\": \"Obj\", \"fields\":[{\"name\": \"age\", \"type\": \"int\"}]}"}' \
  http://localhost:8081/subjects/test-key/versions
# Response:
# {"id":1}

Register a version of a schema using JSON Schema — set the schemaType property:

curl -X POST -H "Content-Type: application/vnd.schemaregistry.v1+json" \
  --data '{"schemaType": "JSON", "schema": "{\"type\": \"object\",\"properties\":{\"age\":{\"type\": \"number\"}},\"additionalProperties\":true}"}' \
  http://localhost:8081/subjects/test-key-json-schema/versions
# Response:
# {"id":2}

List all subjects:

curl -X GET http://localhost:8081/subjects
# Response:
# ["test-key"]

List all versions of a given subject:

curl -X GET http://localhost:8081/subjects/test-key/versions
# Response:
# [1]

Fetch the schema whose global id is 1:

curl -X GET http://localhost:8081/schemas/ids/1
# Response:
# {"schema":"{\"fields\":[{\"name\":\"age\",\"type\":\"int\"}],\"name\":\"Obj\",\"type\":\"record\"}"}

Get version 1 of the schema:

curl -X GET http://localhost:8081/subjects/test-key/versions/1

Get the latest version of the schema under subject test-key:

curl -X GET http://localhost:8081/subjects/test-key/versions/latest

Delete version 10 of the schema registered under subject test-key (if it exists):

curl -X DELETE http://localhost:8081/subjects/test-key/versions/10
# Response:
# 10

Delete all versions of the schema registered under subject test-key:

curl -X DELETE http://localhost:8081/subjects/test-key
# Response:
# [1]

Test the compatibility of a schema with the latest schema under subject test-key:

curl -X POST -H "Content-Type: application/vnd.schemaregistry.v1+json" \
  --data '{"schema": "{\"type\": \"int\"}"}' \
  http://localhost:8081/compatibility/subjects/test-key/versions/latest
# Response:
# {"is_compatible":true}

note

If the subject's compatibility mode is transitive (BACKWARD_TRANSITIVE, FORWARD_TRANSITIVE or FULL_TRANSITIVE), compatibility is checked not only against the latest schema but also against all previous schemas.

Get the current global backwards compatibility setting:

curl -X GET http://localhost:8081/config
# Response:
# {"compatibilityLevel":"BACKWARD"}

Change compatibility requirements for all subjects where it is not otherwise defined:

curl -X PUT -H "Content-Type: application/vnd.schemaregistry.v1+json" \
  --data '{"compatibility": "NONE"}' http://localhost:8081/config
# Response:
# {"compatibility":"NONE"}

Change compatibility requirement to FULL for the test-key subject:

curl -X PUT -H "Content-Type: application/vnd.schemaregistry.v1+json" \
  --data '{"compatibility": "FULL"}' http://localhost:8081/config/test-key
# Response:
# {"compatibility":"FULL"}

REST Proxy

List topics:

curl "http://localhost:8082/topics"

Get info for one particular topic:

curl "http://localhost:8082/topics/my_topic"

Produce a message backed by the schema registry:

curl -H "Content-Type: application/vnd.kafka.avro.v2+json" -X POST -d \
  '{"value_schema": "{\"namespace\": \"example.avro\", \"type\": \"record\", \"name\": \"simple\", \"fields\": [{\"name\": \"name\", \"type\": \"string\"}]}", "records": [{"value": {"name": "name0"}}]}' \
  http://localhost:8082/topics/my_topic

Create a consumer with consumer group avro_consumers and instance my_consumer:

curl -X POST -H "Content-Type: application/vnd.kafka.v2+json" -H "Accept: application/vnd.kafka.v2+json" \
  --data '{"name": "my_consumer", "format": "avro", "auto.offset.reset": "earliest"}' \
  http://localhost:8082/consumers/avro_consumers

Subscribe to the topic:

curl -X POST -H "Content-Type: application/vnd.kafka.v2+json" --data '{"topics":["my_topic"]}' \
  http://localhost:8082/consumers/avro_consumers/instances/my_consumer/subscription

Consume previously produced messages:

curl -X GET -H "Accept: application/vnd.kafka.avro.v2+json" \
  http://localhost:8082/consumers/avro_consumers/instances/my_consumer/records?timeout=1000

Commit offsets for a topic partition:

curl -X POST -H "Content-Type: application/vnd.kafka.v2+json" --data '{}' \
  http://localhost:8082/consumers/avro_consumers/instances/my_consumer/offsets

Delete the consumer:

curl -X DELETE -H "Accept: application/vnd.kafka.v2+json" \
  http://localhost:8082/consumers/avro_consumers/instances/my_consumer