WIP: Add swagger2 compatibility

pom.xml

@@ -53,13 +53,19 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.scm.id>github</project.scm.id>
+        <swagger-parser.version>2.0.1</swagger-parser.version>
     </properties>
 
     <dependencies>
         <dependency>
             <groupId>io.swagger.parser.v3</groupId>
             <artifactId>swagger-parser-v3</artifactId>
-            <version>2.0.1</version>
+            <version>${swagger-parser.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.swagger.parser.v3</groupId>
+            <artifactId>swagger-parser-v2-converter</artifactId>
+            <version>${swagger-parser.version}</version>
         </dependency>
         <dependency>
             <groupId>com.j2html</groupId>

src/test/java/com/qdesrame/openapi/test/Swagger2CompatibilityTest.java

@@ -0,0 +1,20 @@
+package com.qdesrame.openapi.test;
+
+import org.junit.Test;
+
+import static com.qdesrame.openapi.test.TestUtils.assertOpenApiAreEquals;
+
+public class Swagger2CompatibilityTest {
+    private final String SWAGGER_DOC1 = "petstore_swagger2.yaml";
+    private final String OPENAPI_DOC2 = "petstore_openapi3.yaml";
+
+    @Test
+    public void testEqual() {
+        assertOpenApiAreEquals(SWAGGER_DOC1, SWAGGER_DOC1);
+    }
+
+    @Test
+    public void testSwagger2ToOpenapi3() {
+        assertOpenApiAreEquals(SWAGGER_DOC1, OPENAPI_DOC2);
+    }
+}

src/test/resources/petstore_openapi3.yaml

@@ -0,0 +1,109 @@
+openapi: "3.0.0"
+info:
+  version: 1.0.0
+  title: Swagger Petstore
+  license:
+    name: MIT
+servers:
+  - url: http://petstore.swagger.io/v1
+paths:
+  /pets:
+    get:
+      summary: List all pets
+      operationId: listPets
+      tags:
+        - pets
+      parameters:
+        - name: limit
+          in: query
+          description: How many items to return at one time (max 100)
+          required: false
+          schema:
+            type: integer
+            format: int32
+      responses:
+        '200':
+          description: A paged array of pets
+          headers:
+            x-next:
+              description: A link to the next page of responses
+              schema:
+                type: string
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Pets"
+        default:
+          description: unexpected error
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Error"
+    post:
+      summary: Create a pet
+      operationId: createPets
+      tags:
+        - pets
+      responses:
+        '201':
+          description: Null response
+        default:
+          description: unexpected error
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Error"
+  /pets/{petId}:
+    get:
+      summary: Info for a specific pet
+      operationId: showPetById
+      tags:
+        - pets
+      parameters:
+        - name: petId
+          in: path
+          required: true
+          description: The id of the pet to retrieve
+          schema:
+            type: string
+      responses:
+        '200':
+          description: Expected response to a valid request
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Pets"
+        default:
+          description: unexpected error
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Error"
+components:
+  schemas:
+    Pet:
+      required:
+        - id
+        - name
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+        tag:
+          type: string
+    Pets:
+      type: array
+      items:
+        $ref: "#/components/schemas/Pet"
+    Error:
+      required:
+        - code
+        - message
+      properties:
+        code:
+          type: integer
+          format: int32
+        message:
+          type: string

src/test/resources/petstore_swagger2.yaml

@@ -0,0 +1,101 @@
+swagger: "2.0"
+info:
+  version: 1.0.0
+  title: Swagger Petstore
+  license:
+    name: MIT
+host: petstore.swagger.io
+basePath: /v1
+schemes:
+  - http
+consumes:
+  - application/json
+produces:
+  - application/json
+paths:
+  /pets:
+    get:
+      summary: List all pets
+      operationId: listPets
+      tags:
+        - pets
+      parameters:
+        - name: limit
+          in: query
+          description: How many items to return at one time (max 100)
+          required: false
+          type: integer
+          format: int32
+      responses:
+        "200":
+          description: A paged array of pets
+          headers:
+            x-next:
+              type: string
+              description: A link to the next page of responses
+          schema:
+            $ref: '#/definitions/Pets'
+        default:
+          description: unexpected error
+          schema:
+            $ref: '#/definitions/Error'
+    post:
+      summary: Create a pet
+      operationId: createPets
+      tags:
+        - pets
+      responses:
+        "201":
+          description: Null response
+        default:
+          description: unexpected error
+          schema:
+            $ref: '#/definitions/Error'
+  /pets/{petId}:
+    get:
+      summary: Info for a specific pet
+      operationId: showPetById
+      tags:
+        - pets
+      parameters:
+        - name: petId
+          in: path
+          required: true
+          description: The id of the pet to retrieve
+          type: string
+      responses:
+        "200":
+          description: Expected response to a valid request
+          schema:
+            $ref: '#/definitions/Pets'
+        default:
+          description: unexpected error
+          schema:
+            $ref: '#/definitions/Error'
+definitions:
+  Pet:
+    required:
+      - id
+      - name
+    properties:
+      id:
+        type: integer
+        format: int64
+      name:
+        type: string
+      tag:
+        type: string
+  Pets:
+    type: array
+    items:
+      $ref: '#/definitions/Pet'
+  Error:
+    required:
+      - code
+      - message
+    properties:
+      code:
+        type: integer
+        format: int32
+      message:
+        type: string