Fastpath plugin is not sending a Workgroup form to an agent using Spark

[akrherz]

...Migrated from Ignire Jira OF-683...

When a user starts a chat with a Fastpath workgroup JID and fills an automated form (support request), an agent assigned to that group and logged into Spark's Fastpath plugin should get a popup with Accept, Forward buttons and a progress bar until the automatic request forwarding to a next available agent. Currently Saprk shows blank popup and this happens with old Spark version, so the issue must be in Openfire or Openfire's Fasthpath plugin side.

Openfire logs such error upon getting filled form:
[org.jivesoftware.openfire.component.InternalComponentManager$2.error(InternalCo mponentManager.java:338)
]
com.thoughtworks.xstream.converters.ConversionException: Cannot construct org.xmpp.forms.DataForm as it does not have a no-args constructor
---- Debugging information ----

``` message : Cannot construct org.xmpp.forms.DataForm as it does not have a no-args constructor line number : 1 path : /org.xmpp.forms.DataForm cause-message : Cannot construct org.xmpp.forms.DataForm as it does not have a no-args constructor class : org.xmpp.forms.DataForm cause-exception : com.thoughtworks.xstream.converters.reflection.ObjectAccessException required-type : org.xmpp.forms.DataForm ------------------------------- at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:63 ) at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractRef erenceUnmarshaller.java:45) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller. java:46) at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:117) at com.thoughtworks.xstream.core.ReferenceByXPathMarshallingStrategy.unmarshal(Ref erenceByXPathMarshallingStrategy.java:29) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:826) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:813) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:761) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:753) at org.jivesoftware.openfire.fastpath.dataforms.FormManager.getDataForm(FormManage r.java:189) at org.jivesoftware.openfire.fastpath.dataforms.WorkgroupFormProvider.executeGet(W orkgroupFormProvider.java:41) at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.handleIQGet(WorkgroupIQHandl er.java:511) at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.process(WorkgroupIQHandler.j ava:82) at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:424) at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:447) at org.jivesoftware.xmpp.workgroup.WorkgroupManager.processPacket(WorkgroupManager .java:652) at org.jivesoftware.openfire.component.InternalComponentManager$RoutableComponents .process(InternalComponentManager.java:593) at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.jav a:258) at org.jivesoftware.openfire.IQRouter.handle(IQRouter.java:301) at org.jivesoftware.openfire.IQRouter.route(IQRouter.java:101) at org.jivesoftware.openfire.spi.PacketRouterImpl.route(PacketRouterImpl.java:68) at org.jivesoftware.openfire.net.StanzaHandler.processIQ(StanzaHandler.java:311) at org.jivesoftware.openfire.net.ClientStanzaHandler.processIQ(ClientStanzaHandler .java:79) at org.jivesoftware.openfire.net.StanzaHandler.process(StanzaHandler.java:276) at org.jivesoftware.openfire.net.StanzaHandler.process(StanzaHandler.java:175) at org.jivesoftware.openfire.nio.ConnectionHandler.messageReceived(ConnectionHandl er.java:133) at org.apache.mina.common.support.AbstractIoFilterChain$TailFilter.messageReceived (AbstractIoFilterChain.java:570) at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(Ab stractIoFilterChain.java:299) at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilt erChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceive d(AbstractIoFilterChain.java:648) at org.apache.mina.common.IoFilterAdapter.messageReceived(IoFilterAdapter.java:80) at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(Ab stractIoFilterChain.java:299) at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilt erChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceive d(AbstractIoFilterChain.java:648) at org.apache.mina.filter.codec.support.SimpleProtocolDecoderOutput.flush(SimplePr otocolDecoderOutput.java:58) at org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecF ilter.java:185) at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(Ab stractIoFilterChain.java:299) at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilt erChain.java:53) at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceive d(AbstractIoFilterChain.java:648) at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter.java :239) at org.apache.mina.filter.executor.ExecutorFilter$ProcessEventsRunnable.run(Execut orFilter.java:283) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:51) at java.lang.Thread.run(Unknown Source) Caused by: com.thoughtworks.xstream.converters.reflection.ObjectAccessException: Cannot construct org.xmpp.forms.DataForm as it does not have a no-args constructor at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.newIn stance(PureJavaReflectionProvider.java:51) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.inst antiateNewInstance(AbstractReflectionConverter.java:223) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unma rshal(AbstractReflectionConverter.java:117) at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:56 ) ... 44 more

Spark is loggin this error:
org.jivesoftware.spark.util.log.Log error
SEVERE: Unable to retrieve Workgroup form.
item-not-found(404)
at org.jivesoftware.smackx.workgroup.user.Workgroup.getWorkgroupForm(Workgroup.jav a:850)
at org.jivesoftware.fastpath.workspace.panes.ChatQueue.offerRecieved(ChatQueue.jav a:107)
at org.jivesoftware.fastpath.workspace.Workpane$ChatOfferListener.handleOffer(Work pane.java:567)
at org.jivesoftware.fastpath.workspace.Workpane$ChatOfferListener.access$600(Workp ane.java:547)
at org.jivesoftware.fastpath.workspace.Workpane$ChatOfferListener$1.run(Workpane.j ava:554)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

</details>

User reports that replacing xstream.jar solved this, so the problem is with that library https://discourse.igniterealtime.org/t/fastpath-nullpointerexception/54075