[KAFKA-5230] Recommended values for Connect transformations contain the wrong class name

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.10.2.0, 0.10.2.1
• Fix Version/s: 0.10.2.2, 0.11.0.0
• Component/s: connect
• Labels: newbie
• Assignee: Ewen Cheslack-Postava
• Reporter: Ewen Cheslack-Postava
• Reviewer: Gwen Shapira
• Created: 12/May/17 22:49
• Updated: 14/May/17 23:51
• Resolved: 14/May/17 23:51

Description

If you try to validate a connector config with a transformation, it includes suggested values for that config:

curl 'http://localhost:8083/connector-plugins/org.apache.kafka.connect.file.FileStreamSourceConnector/config/validate' -X PUT -H 'Content-Type: application/json' -H 'Accept: */*' --data-binary '{"connector.class":"org.apache.kafka.connect.file.FileStreamSourceConnector","name":"blah-blah","transforms":"something","file":"/tmp/blah.what","topic":"test-topic","tasks.max":1}'

However, some of those recommendations do not contain the correct value:

{
      "definition": {
        "name": "transforms.something.type",
        "type": "CLASS",
        "required": true,
        "default_value": null,
        "importance": "HIGH",
        "documentation": "Class for the 'something' transformation.",
        "group": "Transforms: something",
        "width": "LONG",
        "display_name": "Transformation type for something",
        "dependents": [],
        "order": 0
      },
      "value": {
        "name": "transforms.something.type",
        "value": null,
        "recommended_values": [
          "org.apache.kafka.connect.transforms.ExtractField.Key",
          "org.apache.kafka.connect.transforms.ExtractField.Value",
          "org.apache.kafka.connect.transforms.HoistField.Key",
          "org.apache.kafka.connect.transforms.HoistField.Value",
          "org.apache.kafka.connect.transforms.InsertField.Key",
          "org.apache.kafka.connect.transforms.InsertField.Value",
          "org.apache.kafka.connect.transforms.MaskField.Key",
          "org.apache.kafka.connect.transforms.MaskField.Value",
          "org.apache.kafka.connect.transforms.RegexRouter",
          "org.apache.kafka.connect.transforms.ReplaceField.Key",
          "org.apache.kafka.connect.transforms.ReplaceField.Value",
          "org.apache.kafka.connect.transforms.SetSchemaMetadata.Key",
          "org.apache.kafka.connect.transforms.SetSchemaMetadata.Value",
          "org.apache.kafka.connect.transforms.TimestampRouter",
          "org.apache.kafka.connect.transforms.ValueToKey"
        ],
        "errors": [
          "Missing required configuration \"transforms.something.type\" which has no default value.",
          "Invalid value null for configuration transforms.something.type: Not a Transformation"
        ],
        "visible": true
      }

In particular, nested classes for Key and Value transformations are being returned as, e.g.

org.apache.kafka.connect.transforms.ReplaceField.Key

instead of

org.apache.kafka.connect.transforms.ReplaceField$Key

It seems this is the difference between the canonical and regular name.

Issue Links

• links to: GitHub Pull Request #3044