add validation that Content-Type is supported according to schema

fixes #55

Author: David

src/main/java/com/mservicetech/openapi/common/RequestEntity.java

@@ -1,5 +1,6 @@
 package com.mservicetech.openapi.common;
 
+import com.networknt.oas.model.MediaType;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -64,6 +65,13 @@ public String getContentType() {
     }
 
     public void setContentType(String contentType) {
-        this.contentType = contentType;
+		this.contentType = contentType;
+	}
+
+	public String getContentMediaType() {
+		if(contentType!=null && contentType.contains(";")) {
+			return contentType.substring(0,  contentType.lastIndexOf(";"));
+		}
+		return contentType;
     }
 }

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";
@@ -167,10 +168,15 @@ public Status validateRequestPath (String requestURI , String httpMethod, Reques
         }
 
         if (requestEntity!=null) {
+            if(requestEntity.getContentMediaType()!=null &&
+               openApiOperation.getOperation().getRequestBody().getContentMediaType(requestEntity.getContentMediaType())==null) {
+                return new Status(STATUS_CONTENT_TYPE_NOT_SUPPORTED, requestEntity.getContentMediaType());
+            }
+
             NormalisedPath requestPath = openApiOperation.getPathString();
             Status status = validateRequestParameters(requestEntity, requestPath, openApiOperation);
             if(status != null) return status;
-            if ((requestEntity.getContentType()==null || requestEntity.getContentType().startsWith("application/json"))) {
+            if ((requestEntity.getContentType()==null || requestEntity.getContentMediaType().equals("application/json"))) {
                 try {
                     Object body = attachJsonBody(requestEntity.getRequestBody());
                     status = validateRequestBody(body, openApiOperation);

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

@@ -126,7 +126,20 @@ public void testRequestBodyNull() {
     }
 
 
-    @Test
+	@Test
+	public void testRequestBodyContentTypeWithEncoding() {
+		InputStream in = this.getClass().getClassLoader().getResourceAsStream("json/req1.json");
+		String req1 = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8)).lines().collect(Collectors.joining("\n"));
+
+		RequestEntity requestEntity = new RequestEntity();
+		requestEntity.setRequestBody(req1);
+		requestEntity.setContentType("application/json; charset=utf-8");
+		Status status = openApiValidator.validateRequestPath("/pets", "post", requestEntity);
+		Assert.assertNull(status);
+	}
+
+
+	@Test
     public void testRequestPath() {
 
         RequestEntity requestEntity = new RequestEntity();
@@ -369,6 +382,32 @@ 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");