Validator

Validator performs declarative validation of the message according to the declared Input Type and/or Output Type on a route definition which declares the expected message type.

Currently, validators is only supported in Java DSL and the classic Spring XML.

Data type format

scheme:name

where scheme is the type of data model like java, xml or json, and name is the individual data type name.

Supported Validators

Validator Description

Predicate Validator

Validate with using Expression or Predicate

Endpoint Validator

Validate by forwarding to the Endpoint to be used with validation component such as Validation Component or Bean Validation Component.

Custom Validator

Validate with using custom validator class. Validator must be a subclass of org.apache.camel.spi.Validator

Common Options

All validators have following common options to specify which data type is supported by the validator. type must be specified.

Name Description

type

Data type to validate

Predicate Validator Options

Name Description

expression

Expression or Predicate to be used for validation

Here is an example to specify a validation predicate:

  • Java

  • Spring XML

validator()
    .type("csv:CSVOrder")
    .withExpression(bodyAs(String.class).contains("{name:XOrder}"));
<predicateValidator Type="csv:CSVOrder">
    <simple>${body} contains '{name:XOrder}'</simple>
</predicateValidator>

Endpoint Validator Options

Name Description

ref

Reference to the Endpoint ID

uri

Endpoint URI

Here is an example to specify endpoint URI in Java DSL:

  • Java

  • Spring XML

validator()
    .type("xml")
    .withUri("validator:xsd/schema.xsd");
<endpointValidator uri="validator:xsd/schema.xsd" type="xml"/>

Note that the Endpoint Validator just forwards the message to the specified endpoint. In above example, camel forwards the message to the validator: endpoint, which actually is a Validation Component. You can also use any other validation component like Bean Validation Component.

Custom Validator Options

The validator must be an implementation of org.apache.camel.spi.Validator

Name Description

ref

Reference to the custom Validator bean ID

className

Fully qualified class name of the custom Validator class

Here is an example to specify custom Validator class:

  • Java

  • Spring XML

validator()
    .type("json")
    .withJava(com.example.MyCustomValidator.class);
<customTransformer className="com.example.MyCustomValidator" type="json"/>

Examples

For example to declare the Endpoint Validator which uses validator component to validate xml:ABCOrder, we can do as follows:

  • Java

  • Spring XML

validator()
    .type("xml:ABCOrder")
    .withUri("validator:xsd/schema.xsd");
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
    <validators>
        <endpointValidator uri="validator:xsd/schema.xsd" type="xml:ABCOrder"/>
    </validators>
</camelContext>

If you have the following route definition, above validator will be applied when direct:abc endpoint receives the message. Note that inputTypeWithValidate is used instead of inputType in Java DSL, and the validate attribute on the inputType declaration is set to true in XML DSL:

  • Java

  • Spring XML

from("direct:abc")
    .inputTypeWithValidate("xml:ABCOrder")
    .log("${body}");
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
    <route>
        <from uri="direct:abc"/>
        <inputType urn="xml:ABCOrder" validate="true"/>
        <log message="${body}"/>
    </route>
</camelContext>

See Also

The Transformer is a related functionality.

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