json_schema

Checks messages against a provided JSONSchema definition but does not change the payload under any circumstances. If a message does not match the schema it can be caught using error handling methods.

# Config fields, showing default values
label: ""
json_schema:
  schema: "" # No default (optional)
  schema_path: "" # No default (optional)

Please refer to the JSON Schema website for information and tutorials regarding the syntax of the schema.

Fields

schema

A schema to apply. Use either this or the schema_path field.

Type: string

schema_path

The path of a schema document to apply. Use either this or the schema field.

Type: string

Examples

With the following JSONSchema document:

{
  "$id": "https://example.com/person.schema.json",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "Person",
  "type": "object",
  "properties": {
    "firstName": {
    "type": "string",
    "description": "The person's first name."
    },
    "lastName": {
    "type": "string",
    "description": "The person's last name."
    },
    "age": {
    "description": "Age in years which must be equal to or greater than zero.",
    "type": "integer",
    "minimum": 0
    }
  }
}

And the following Redpanda Connect configuration:

pipeline:
  processors:
  - json_schema:
      schema_path: "file://path_to_schema.json"
  - catch:
    - log:
        level: ERROR
        message: "Schema validation failed due to: ${!error()}"
    - mapping: 'root = deleted()' # Drop messages that fail

If a payload being processed looked like:

{"firstName":"John","lastName":"Doe","age":-21}

Then a log message would appear explaining the fault and the payload would be dropped.