Falcon CLI list entities operation throws NullPointerException

Using falcon v0.6 and doing list entities I receive NullPointerException. This happens only on falcon installations that had existing entities and got upgraded to 0.6. I run:

falcon entity -type cluster -list
falcon entity -type process -list

and I get this on console:

Stacktrace:
org.apache.falcon.client.FalconCLIException: Bad Request;null
at org.apache.falcon.client.FalconCLIException.fromReponse(FalconCLIException.java:44)
at org.apache.falcon.client.FalconClient.checkIfSuccessful(FalconClient.java:1172)
at org.apache.falcon.client.FalconClient.sendListRequest(FalconClient.java:791)
at org.apache.falcon.client.FalconClient.getEntityList(FalconClient.java:374)
at org.apache.falcon.cli.FalconCLI.entityCommand(FalconCLI.java:412)
at org.apache.falcon.cli.FalconCLI.run(FalconCLI.java:183)
at org.apache.falcon.cli.FalconCLI.main(FalconCLI.java:133)

The stacktrace on the server shows:

2015-03-03 04:14:06,462 ERROR - [683216314@qtp-1027439921-0:68e05a5c-95cb-46fb-a9f0-a7280e491dc2 falcon:GET//entities/list/process] ~ Failed to get entity list (AbstractEntityManager:532)
java.lang.NullPointerException
at org.apache.falcon.resource.AbstractEntityManager.tryProxy(AbstractEntityManager.java:353)
at org.apache.falcon.resource.AbstractEntityManager.getEntities(AbstractEntityManager.java:583)
at org.apache.falcon.resource.AbstractEntityManager.getEntityList(AbstractEntityManager.java:530)
at org.apache.falcon.resource.proxy.SchedulableEntityManagerProxy.getEntityList(SchedulableEntityManagerProxy.java:405)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:185)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:288)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1469)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1400)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)
at org.apache.falcon.security.FalconAuthorizationFilter.doFilter(FalconAuthorizationFilter.java:102)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
at org.apache.falcon.security.FalconAuthenticationFilter$2.doFilter(FalconAuthenticationFilter.java:184)
at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:572)
at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:542)
at org.apache.falcon.security.FalconAuthenticationFilter.doFilter(FalconAuthenticationFilter.java:193)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
at org.apache.falcon.security.FalconAuditFilter.doFilter(FalconAuditFilter.java:65)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
2015-03-03 04:14:06,463 ERROR - [683216314@qtp-1027439921-0:68e05a5c-95cb-46fb-a9f0-a7280e491dc2 falcon:GET//entities/list/process] ~ Action failed: Bad Request
Error: null (FalconWebException:68)

This happened when upgrading falcon to 0.6. Cluster/process definitions do not contain ACLs. Looking at AbstractEntityManager.java source the problem is obvious:

private void tryProxy(Entity entity) throws IOException, FalconException {
final String aclOwner = entity.getACL().getOwner();
final String aclGroup = entity.getACL().getGroup();

tryProxy method does not check if entity.getACL() returns null. There is a method called decorateEntityWithACL which is used as a kludge before invoking tryProxy method and it populates entities with some sample ACL and tryProxy does not throw null pointer exception. This is done in submitInternal() and update() methods in AbstractEntityManager.java, which are called when we call submit or update. However the list CLI operation calls getEntities() method, which calls tryProxy() but does not "decorate" the entity with decorateEntityWithACL() and hence we get NullPointerException.

This bug affects falcon UI as well. I checked trunk and it is not fixed there as well. This bug won't manifest on entities created on falcon 0.6 because falcon "injects" ACLs into the entity definition before saving it to Configuration Store if it does not have one already.