diff --git a/commons-error/src/main/java/eu/europeana/api/commons/error/EuropeanaApiErrorAttributes.java b/commons-error/src/main/java/eu/europeana/api/commons/error/EuropeanaApiErrorAttributes.java
index b5c626f7..857868cb 100644
--- a/commons-error/src/main/java/eu/europeana/api/commons/error/EuropeanaApiErrorAttributes.java
+++ b/commons-error/src/main/java/eu/europeana/api/commons/error/EuropeanaApiErrorAttributes.java
@@ -54,7 +54,7 @@ private void addPathRequestParameters(Map<String, Object> errorAttributes, WebRe
             String paramName = it.next();
             s.append(paramName);
             String paramValue = webRequest.getParameter(paramName);
-            if (!StringUtils.isEmpty(paramValue)) {
+            if (StringUtils.hasText(paramValue)) {
                 s.append("=").append(paramValue);
             }
         }
diff --git a/commons-web/pom.xml b/commons-web/pom.xml
index 1fe78c87..e4248d0c 100644
--- a/commons-web/pom.xml
+++ b/commons-web/pom.xml
@@ -74,7 +74,7 @@
             <version>${version.springBoot}</version>
             <scope>provided</scope>
         </dependency>
-		 
+         
 		<dependency>
 			<groupId>org.apache.logging.log4j</groupId>
 			<artifactId>log4j-core</artifactId>
diff --git a/commons-web/src/main/java/eu/europeana/api/commons/web/controller/BaseRestController.java b/commons-web/src/main/java/eu/europeana/api/commons/web/controller/BaseRestController.java
index 044b2e3d..c9f1afcb 100644
--- a/commons-web/src/main/java/eu/europeana/api/commons/web/controller/BaseRestController.java
+++ b/commons-web/src/main/java/eu/europeana/api/commons/web/controller/BaseRestController.java
@@ -79,8 +79,7 @@ public String generateETag(Date timestamp, String format, String version) {
         serialCode += "0.0.1-SNAPSHOT".hashCode();
       }
         
-      // see also https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/ETag
-      return "W/\"" + Long.toHexString(serialCode)  + "\"";
+      return "\"" + Long.toHexString(serialCode)  + "\"";
     }
 
   /**
@@ -90,10 +89,13 @@ public String generateETag(Date timestamp, String format, String version) {
    */
   protected String getMethodsForRequestPattern(HttpServletRequest request,
       AbstractRequestPathMethodService requestMethodService) {
-    Optional<String> methodsForRequestPattern =
+    if(requestMethodService != null) {
+      Optional<String> methodsForRequestPattern =
         requestMethodService.getMethodsForRequestPattern(request);
-
-    return methodsForRequestPattern.orElse(request.getMethod());
+      return methodsForRequestPattern.orElse(request.getMethod());
+    }else {
+      return request.getMethod();
+    }
   }
 
 }
diff --git a/commons-web/src/main/java/eu/europeana/api/commons/web/exception/EuropeanaGlobalExceptionHandler.java b/commons-web/src/main/java/eu/europeana/api/commons/web/exception/EuropeanaGlobalExceptionHandler.java
index 1110d956..9a5e4a1e 100644
--- a/commons-web/src/main/java/eu/europeana/api/commons/web/exception/EuropeanaGlobalExceptionHandler.java
+++ b/commons-web/src/main/java/eu/europeana/api/commons/web/exception/EuropeanaGlobalExceptionHandler.java
@@ -216,11 +216,23 @@ public ResponseEntity<EuropeanaApiErrorResponse> handleMethodArgNotValidExceptio
     
     protected HttpHeaders createHttpHeaders(HttpServletRequest httpRequest) {
       HttpHeaders headers = new HttpHeaders();
+      //enforce application/json as content type, it is the only serialization supported for exceptions
       headers.setContentType(MediaType.APPLICATION_JSON);
-      if(requestPathMethodService!=null) {
-        String allowHeaderValue = requestPathMethodService.getMethodsForRequestPattern(httpRequest).orElse(httpRequest.getMethod());
+      
+      //autogenerate allow header if the service is configured
+      if(getRequestPathMethodService()!=null) {
+        String allowHeaderValue = getRequestPathMethodService().getMethodsForRequestPattern(httpRequest).orElse(httpRequest.getMethod());
         headers.add(HttpHeaders.ALLOW, allowHeaderValue);
       }
       return headers;
     }
+
+    /**
+     * The bean needs to be defined in the individual APIs
+     * 
+     * @return
+     */
+    AbstractRequestPathMethodService getRequestPathMethodService() {
+      return requestPathMethodService;
+    }
 }