This is the swagger parser project, which reads OpenAPI Specifications into current Java POJOs. It also provides a simple framework to add additional converters from different formats into the Swagger objects, making the entire toolchain available.

The goal of Swagger™ is to define a standard, language-agnostic interface to REST APIs which allows both humans and computers to discover and understand the capabilities of the service without access to source code, documentation, or through network traffic inspection. When properly defined via Swagger, a consumer can understand and interact with the remote service with a minimal amount of implementation logic. Similar to what interfaces have done for lower-level programming, Swagger removes the guesswork in calling the service.

Check out Swagger-Spec for additional information about the Swagger project, including additional libraries with support for other languages and more.

Using the swagger-parser is simple. Once included in your project, you can read a OpenAPI Specification from any location:

import io.swagger.parser.SwaggerParser;
import io.swagger.models.Swagger;

// ... your code

  // read a swagger description from the petstore
  Swagger swagger = new SwaggerParser().read("http://petstore.swagger.io/v2/swagger.json");

You can read from a file location as well:

  Swagger swagger = new SwaggerParser().read("./path/to/swagger.json");

And with the swagger-compat-spec-parser module, you can read older formats, and convert them into swagger 2.0:

  Swagger swagger = new SwaggerCompatConverter().read("http://petstore.swagger.io/api/api-docs");

If your swagger resource is protected, you can pass headers in the request:

import io.swagger.models.auth.AuthorizationValue;

// ... your code

  // build a authorization value
  AuthorizationValue mySpecialHeader = new AuthorizationValue()
    .keyName("x-special-access")  //  the name of the authorization to pass
    .value("i-am-special")        //  the value of the authorization
    .type("header");              //  the location, as either `header` or `query`

  // or in a single constructor
  AuthorizationValue apiKey = new AuthorizationValue("api_key", "special-key", "header");
  Swagger swagger = new SwaggerParser().read(
    "http://petstore.swagger.io/v2/swagger.json",
    Arrays.asList(mySpecialHeader, apiKey)
  );

And, if your intent is to read in a Swagger 1.2 spec so that you can then output a Swagger 2 spec to string/file then you are in luck - you have the spec in pojo form, now pass it to pretty() and you're good to go.

    String swaggerString = Json.pretty(swagger);

You need the following installed and available in your $PATH:

• Java 1.7
• Apache maven 3.0.3 or greater

After cloning the project, you can build it from source with this command:

mvn package

This project has a core artifact--swagger-parser, which uses Java Service Provider Inteface (SPI) so additional extensions can be added. To read Swagger 1.0, 1.1, and 1.2 specifications, a module is included called swagger-compat-spec-parser. This reads those older versions of the spec and produces 2.0 objects.

To build your own extension, you simply need to create a src/main/resources/META-INF/services/io.swagger.parser.SwaggerParserExtension file with the full classname of your implementation. Your class must also implement the io.swagger.parser.SwaggerParserExtension interface. Then, including your library with the swagger-parser module will cause it to be triggered automatically.

You can include this library from Sonatype OSS for SNAPSHOTS, or Maven central for releases. In your dependencies:

<dependency>
  <groupId>io.swagger</groupId>
  <artifactId>swagger-parser</artifactId>
  <version>1.0.21</version>
</dependency>

To add swagger parsing support for older versions of swagger, add the compat module. Since it depends on swagger-parser, you don't need to include both:

<dependency>
  <groupId>io.swagger</groupId>
  <artifactId>swagger-compat-spec-parser</artifactId>
  <version>1.0.21</version>
</dependency>

Copyright 2016 SmartBear Software

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.