Custom ServletFilterHolder for CORS Headers not working

Hello,

After a suggestion from Eric Tschetter over on this thread (https://groups.google.com/forum/#!topic/druid-development/y01WJAp-UBc), I’ve started to make a CORS Servlet Filter but I’m having trouble making it work. I’ve created my module and added it to druid and I even see druid load it in the logs, but it seems like my filter is never used. I am not 100% sure I set everything up right though, especially the Path and DispatcherTypes in the ServletFilterHolder. Here is what I have so far:

The DruidModule:

public class CORSFilterExtension implements DruidModule {

@Override

public List<? extends Module> getJacksonModules() {

return ImmutableList.of();

}

@Override

public void configure(Binder binder) {

Multibinder multibinder = Multibinder.newSetBinder(binder, ServletFilterHolder.class);

multibinder.addBinding().to(SimpleCORSServletFilterHolder.class);

}

}

``

The SimpleCORSServletFilterHolder:

public class SimpleCORSServletFilterHolder implements ServletFilterHolder {

public SimpleCORSServletFilterHolder() {

}

@Override

public Filter getFilter() {

return new SimpleCORSServletFilter();

}

@Override

public Class<? extends Filter> getFilterClass() {

return SimpleCORSServletFilter.class;

}

@Override

public Map<String, String> getInitParameters() {

Map<String, String> initParams = new HashMap<>();

return initParams;

}

@Override

public String getPath() {

return “/*”;

}

@Override

public EnumSet getDispatcherType() {

return EnumSet.of(DispatcherType.REQUEST, DispatcherType.ASYNC);

}

}

``

And the SimpleCORSServletFilter:

public class SimpleCORSServletFilter implements Filter {

private static final Logger log = Logger.getLogger(SimpleCORSServletFilter.class);

@Override

public void init(FilterConfig filterConfig) throws ServletException {

}

@Override

public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

log.info(“Adding Access Control Response Headers”);

HttpServletResponse response = (HttpServletResponse) servletResponse;

response.setHeader(“Access-Control-Allow-Origin”, “*”);

response.setHeader(“Access-Control-Allow-Credentials”, “true”);

response.setHeader(“Access-Control-Allow-Methods”, “POST, GET, HEAD, OPTIONS”);

response.setHeader(“Access-Control-Allow-Headers”, “Origin, Accept, X-Requested-With, Content-Type, Access-Control-Request-Method, Access-Control-Request-Headers”);

filterChain.doFilter(servletRequest, servletResponse);

}

@Override

public void destroy() {

}

}

``

After deploying this, I have a webapp that is trying to submit an AJAX POST to the Broker’s API @ /druid/v2/?pretty but I get the error:

XMLHttpRequest cannot load http://192.168.59.103:8084/druid/v2/?pretty. No ‘Access-Control-Allow-Origin’ header is present on the requested resource. Origin ‘http://localhost:1337’ is therefore not allowed access. The response had HTTP status code 500.

``

In the druid logs I just see an exception about an invalid query:

druid_1 | 2015-04-16 20:20:57,466 DEBG ‘druid-realtime’ stdout output:

druid_1 | 2015-04-16T20:20:57,464 WARN [qtp1458958776-35] io.druid.server.QueryResource - Exception occurred on request [unparsable query]

druid_1 | com.fasterxml.jackson.databind.JsonMappingException: No content to map due to end-of-input

druid_1 | at [Source: HttpInputOverHTTP@229757c0; line: 1, column: 1]

druid_1 | at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:148) ~[druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:3110) ~[druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:3051) ~[druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2207) ~[druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at io.druid.server.QueryResource.doPost(QueryResource.java:133) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.7.0_76]

druid_1 | at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[?:1.7.0_76]

druid_1 | at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.7.0_76]

druid_1 | at java.lang.reflect.Method.invoke(Method.java:606) ~[?:1.7.0_76]

druid_1 | at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:205) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1511) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1442) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1391) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1381) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:538) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:716) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.ServletDefinition.doServiceImpl(ServletDefinition.java:278) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.ServletDefinition.doService(ServletDefinition.java:268) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.ServletDefinition.service(ServletDefinition.java:180) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.ManagedServletPipeline.service(ManagedServletPipeline.java:93) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:85) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.ManagedFilterPipeline.dispatch(ManagedFilterPipeline.java:120) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.GuiceFilter$1.call(GuiceFilter.java:132) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.GuiceFilter$1.call(GuiceFilter.java:129) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.GuiceFilter$Context.call(GuiceFilter.java:206) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at com.google.inject.servlet.GuiceFilter.doFilter(GuiceFilter.java:129) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:83) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:364) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:221) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.Server.handle(Server.java:497) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:620) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:540) [druid-services-0.7.1.1-selfcontained.jar:0.7.1.1]

druid_1 | at java.lang.Thread.run(Thread.java:745) [?:1.7.0_76]

``

And I never see the log statement from my servlet. So it seems to load my extension, but maybe never register it? Or maybe I need to change the path or something? Oh an I am running 0.7.1.1. Any help with what I’m doing wrong would be great!

Thanks

Andrew

Hi Andrew,
I am not very familiar with filters but you can have a look at DumyAuthFilter in BasicJettyTest as an example of working filter.

(https://github.com/druid-io/druid/blob/master/server/src/test/java/io/druid/server/initialization/BaseJettyTest.java)

Another example in druid code base if RedirectFilter.

I figured it out and it was a “DOH!” moment. I forgot to include the META-INF/services property file so it was never loading my module…

Thanks for the examples to look at though. They at least got me to fix a few things. Thanks!

Andrew

Andrew,
Can you share the piece of code and how to integrate into Druid.

Or was it made part of Druid core ?

I am facing the same error.

Regards,

Deepak

I created a DruidModule and see it working now. After several hours of beating the bush :slight_smile:
http://druid.io/docs/latest/development/modules.html

Sorry I didn’t see this eariler, but I did open source the filter we were using:

Might be too late, but feel free to check it out!

Andrew

Hi,

I was following this thread closely for CORS error facing while querying druid from browser.

I was able to perform below steps:

  1. Loaded the cors filter extension with below command
java \
  -cp "lib/*" \
  -Ddruid.extensions.directory="extensions" \
  -Ddruid.extensions.hadoopDependenciesDir="hadoop-dependencies" \
  org.apache.druid.cli.Main tools pull-deps \
  --no-default-hadoop \
  -c "net.acesinc.druid.extensions:cors-servlet-filter:1.0.0"
  1. This created a new extension cors-servlet-filter in extensions folder with related jars

  2. I set the below field option to true

druid.auth.allowUnauthenticatedHttpOptions

  1. I was able to start the druid cluster successfully

I still see CORS error while querying data

Could you help me out here if i am missing any step

Hi Shashank, What version of Druid are you trying to use it with? Someone else reported a bug with it not working in the latest. I think the extension refactor in 0.9 broke our extension and haven’t have a chance to fix it. You can see the issue here: https://github.com/everwatchsolutions/druid-cors-filter-extension/issues/3

Hi Andrew,
Im using with 0.15.0 version. I dont see any exceptions after integrating with cors filter though.

Regards
Shashank