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Chapter 178. JSON Schema Validator Component

Available as of Camel version 2.20

The JSON Schema Validator component performs bean validation of the message body against JSON Schemas v4 draft using the NetworkNT JSON Schema library (https://github.com/networknt/json-schema-validator).

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-json-validator</artifactId>
    <version>x.y.z</version>
    <!-- use the same version as your Camel core version -->
</dependency>

178.1. URI format

json-validator:resourceUri[?options]

Where resourceUri is some URL to a local resource on the classpath or a full URL to a remote resource or resource on the file system which contains the JSON Schema to validate against.

178.2. URI Options

The JSON Schema Validator component has no options.

The JSON Schema Validator endpoint is configured using URI syntax:

json-validator:resourceUri

with the following path and query parameters:

178.2.1. Path Parameters (1 parameters):

NameDescriptionDefaultType

resourceUri

Required Path to the resource. You can prefix with: classpath, file, http, ref, or bean. classpath, file and http loads the resource using these protocols (classpath is default). ref will lookup the resource in the registry. bean will call a method on a bean to be used as the resource. For bean you can specify the method name after dot, eg bean:myBean.myMethod.

 

String

178.2.2. Query Parameters (7 parameters):

NameDescriptionDefaultType

contentCache (producer)

Sets whether to use resource content cache or not

false

boolean

failOnNullBody (producer)

Whether to fail if no body exists.

true

boolean

failOnNullHeader (producer)

Whether to fail if no header exists when validating against a header.

true

boolean

headerName (producer)

To validate against a header instead of the message body.

 

String

errorHandler (advanced)

To use a custom ValidatorErrorHandler. The default error handler captures the errors and throws an exception.

 

JsonValidatorError Handler

schemaLoader (advanced)

To use a custom schema loader allowing for adding custom format validation. The default implementation will create a schema loader with draft v4 support.

 

JsonSchemaLoader

synchronous (advanced)

Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported).

false

boolean

178.3. Example

Assumed we have the following JSON Schema

myschema.json

{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "definitions": {},
  "id": "my-schema",
  "properties": {
    "id": {
      "default": 1,
      "description": "An explanation about the purpose of this instance.",
      "id": "/properties/id",
      "title": "The id schema",
      "type": "integer"
    },
    "name": {
      "default": "A green door",
      "description": "An explanation about the purpose of this instance.",
      "id": "/properties/name",
      "title": "The name schema",
      "type": "string"
    },
    "price": {
      "default": 12.5,
      "description": "An explanation about the purpose of this instance.",
      "id": "/properties/price",
      "title": "The price schema",
      "type": "number"
    }
  },
  "required": [
    "name",
    "id",
    "price"
  ],
  "type": "object"
}

we can validate incoming JSON with the following Camel route, where myschema.json is loaded from the classpath.

from("direct:start")
  .to("json-validator:myschema.json")
  .to("mock:end")