bjansen/swagger-schema-validator

Validates JSON objects against Swagger 2 definitions

Swagger schema validator

This library validates JSON objects against models defined in the definitions section of a Swagger 2 specification.

InputStream spec = getClass().getResourceAsStream("mySpec.yaml");
SwaggerValidator validator = SwaggerValidator.forYamlSchema(spec);

ProcessingReport report = validator.validate("{\"name\": \"Bob\"}", "/definitions/User");

if (report.isSuccess()) {
    doStuff();
}

Installation

This library is available on Maven Central:

<dependency>
    <groupId>com.github.bjansen</groupId>
    <artifactId>swagger-schema-validator</artifactId>
    <version>1.0.0</version>
</dependency>

Additional schema validations

In addition to the subset of JSON-Schema Draft 4 already supported by Swagger 2 specifications, this library adds support for the following JSON-Schema validation keywords:

Keyword	Description
additionalItems	See #rfc.section.6.4.2
contains	See #rfc.section.6.4.6
patternProperties	See #rfc.section.6.5.5
dependencies	See #rfc.section.6.5.7
propertyNames	See #rfc.section.6.5.8
if	See #rfc.section.6.6.1
then	See #rfc.section.6.6.2
else	See #rfc.section.6.6.3
allOf	See #rfc.section.6.7.1
anyOf	See #rfc.section.6.7.2
oneOf	See #rfc.section.6.7.3
not	See #rfc.section.6.7.4

To use them in a Swagger 2 spec, simply prefix them with x-, like this:

definitions:
  User:
    x-oneOf: [{required: ["id"]}, {required: ["name"]}]
    properties:
      id:
        type: integer
      name:
        type: string

In the example above, a User will be valid if it contains either an id or a name.

Custom schemas and validation keywords

In case you need more than the default factory methods to parse JSON/YAML schemas, or need to do extra keywords transformations (like automatically renaming x-oneof to x-oneOf in schemas you don't control), you can use this factory method that was introduced in 1.0.0:

JsonNode schema = Json.mapper().readTree(getClass().getResourceAsStream("schema.json"));
Map<String, String> transformations = Map.of("x-oneof", "x-oneOf");

SwaggerValidator validator = SwaggerValidator.forJsonNode(schema, transformations);

Custom transformations will be applied before built-in ones, so in this case it will go x-oneof -> x-oneOf -> oneOf.

How it works

This library is a bridge between a Swagger schema parser provided by swagger-core and a general-purpose JSON schema validator provided by json-schema-validator.

As a consequence, it is pretty much limited to the features these two libraries offer.