add validation that Content-Type is supported according to schema

fixes #55

Author: David

src/main/java/com/mservicetech/openapi/validation/OpenApiValidator.java

@@ -44,6 +44,7 @@ public class OpenApiValidator {
     final String STATUS_INVALID_REQUEST_PATH = "ERR10007";
     final String STATUS_METHOD_NOT_ALLOWED = "ERR10008";
     final String STATUS_CONTENT_TYPE_MISMATCH = "ERR10015";
+    final String STATUS_CONTENT_TYPE_NOT_SUPPORTED = "ERR11108";
 
     final String VALIDATOR_REQUEST_BODY_UNEXPECTED = "ERR11013";
     final String VALIDATOR_REQUEST_BODY_MISSING = "ERR11014";
@@ -167,6 +168,11 @@ public Status validateRequestPath (String requestURI , String httpMethod, Reques
         }
 
         if (requestEntity!=null) {
+            if(requestEntity.getContentType()!=null &&
+               openApiOperation.getOperation().getRequestBody().getContentMediaType(requestEntity.getContentType())==null) {
+                return new Status(STATUS_CONTENT_TYPE_NOT_SUPPORTED, requestEntity.getContentType());
+            }
+
             NormalisedPath requestPath = openApiOperation.getPathString();
             Status status = validateRequestParameters(requestEntity, requestPath, openApiOperation);
             if(status != null) return status;

src/test/java/com/mservicetech/openapi/validation/OpenApiValidatorTest.java

@@ -369,6 +369,32 @@ public void testRequestQueryFormObjectWithErrorMissingValue() {
         //{"statusCode":400,"code":"ERR11004","message":"VALIDATOR_SCHEMA","description":"Schema Validation Error - search.name: must be at least 1 characters long","severity":"ERROR"}
     }
 
+    @Test
+    public void testRequestMediaType() {
+        RequestEntity requestEntity = new RequestEntity();
+        Map<String, Object> queryMap = new HashMap<>();
+        requestEntity.setQueryParameters(queryMap);
+        requestEntity.setContentType("application/xml");
+        Status status = openApiValidator.validateRequestPath("/pets", "post", requestEntity);
+        Assert.assertNotNull(status);
+        Assert.assertEquals(status.getCode(), "ERR11108");
+    }
+
+
+    @Test
+    public void testRequestMediaType2() {
+        RequestEntity requestEntity = new RequestEntity();
+        Map<String, Object> queryMap = new HashMap<>();
+        queryMap.put("limit", 12);
+        queryMap.put("search", "tag,cat,name");
+        requestEntity.setQueryParameters(queryMap);
+        requestEntity.setContentType("application/json");
+        Status status = openApiValidator.validateRequestPath("/pets", "get", requestEntity);
+        Assert.assertNotNull(status);
+        Assert.assertEquals(status.getCode(), "ERR11108");
+    }
+
+
     @Test
     public void testResponseBody() {
         InputStream in = this.getClass().getClassLoader().getResourceAsStream("json/req1.json");