CORS - Response does not include Access-Control headers for GET request

[Tuong-Nguyen]

I configure CORS settings in kafka-rest.properties file as follow:

access.control.allow.origin=* access.control.allow.methos="GET,POST,PUT,DELETE"

The responses for POST - DELETE requests have Access-Control values in header. However, the GET requests does not have them and Browser may reject the response.

1- If the GET request does not contain Content-Type header, Browser accept the response. 2- If the GET request contains Content-Type header (ex: Content-Type: application/vnd.kafka.json.v2+json), Browser will reject the response.

Confluent Kafka REST should return Access-Control in response because it is configured in the kafka-rest.properties file.

[JozeFe]

same issue.

[qi4589746]

access.control.allow.origin=* access.control.allow.methods=GET,POST,PUT,DELETE

[Devon-Peroutky]

Same issue. Is there any update?

[parallaxisjones]

same issue.

[ankitbansal]

Same issue. Also do we have support for Access-Control-Allow-Headers?

[cxk280]

Same issue here.

[churtado]

Same

[abeer-noor]

Same issue.

[Chrislevi]

Same issue. its already configured by default but im still getting CONNECTION ERROR through reverse-proxy(Traefik).. but directly it works..

@ewencp Can any of the devs comment?

[CTodd20]

Same problem, has this been looked at?

[jairsjunior]

Same problem here, but after some time spent looking at the code, i saw that the class io.confluent.rest.RestConfig has one more related property access.control.allow.headers that can be set. Setting this property makes everything works correctly. At the documentation of kafka-rest this property isn't listed.

To use CORS on kafka-rest we need to set this 3 lines at the kafka-rest.properties:

access.control.allow.origin=*
access.control.allow.methos=GET,POST,PUT,DELETE
access.control.allow.headers=origin,content-type,accept,authorization

[raymond-ong]

Thank you @jairsjunior To expound on it, I had to modify the file kafka-rest.properties inside ../confluent-6.0.0/etc/kafka-rest folder, then restart the REST server.

[Caruso33]

For the ones using the docker-compose file that would correspond to the environment entries:

environment:
      ...
      KAFKA_REST_ACCESS_CONTROL_ALLOW_ORIGIN: "*"
      KAFKA_REST_ACCESS_CONTROL_ALLOW_METHODS: "GET,POST,PUT,DELETE"
      KAFKA_REST_ACCESS_CONTROL_ALLOW_HEADERS: "origin,content-type,accept,authorization"