On Wednesday, October 24, 2018 at 7:21:08 AM UTC+2, Anastasiya Ruzhanskaya wrote: > > Also I notice that there might be such situation: there is a java list of > elements, but instead of writing that this is a list type and it has 0 > elements, I just have 0. > Also for guid: there can stand also only 0 without specifying that this > is guid type. I am not sure that it is impossible to determine this type in > runtime as previously in the same message I already had guid fields. > > For the example that I sent, the last numbers correspond to the following: > > 14(TransactionScopeOption)|2(enum, =required)| > 0(useCinderCommandCallback)| (bool) > 0(vdsRunningOn, null, guid)| (Guid) > 0(vdsmTaskIds)| (List) > 0(first last bool param)| > 0(second last bool param)| > > The vdsRunningOn and vdsmTaskIds are 'null'. Specifically, vdsmTaskIds is not an empty list, it's 'null'; as in "vdsmTaskIds == null" would be 'true', and "vdsmTaskIds.isEmpty()" would throw a NullPointerException.
> > вторник, 23 октября 2018 г., 14:50:33 UTC+3 пользователь Thomas Broyer > написал: >> >> >> >> On Tuesday, October 23, 2018 at 1:16:57 PM UTC+2, Anastasiya Ruzhanskaya >> wrote: >>> >>> Dear Thomas, >>> thank you a lot for a detailed answer! >>> >>> I saw this documentation, but seems should look more thoroughly into >>> serialization inside GWT. >>> >>> Concerning the numbers 0|5|0|0|0 - after VmOperationParameterBase class >>> where there is a private field vmId we move down to ActionParameterBase >>> class (as you said), so 0 here will correspond to the first parameter >>> inside this class in alphabetical order (seems commanId)? And five - to >>> some value or to a type of parameter? (sometimes it is not clear does the >>> payload mean the type or the value itself). There is a field there - >>> ActionType commandType; which has type 5. >>> >> >> From the doc, if the declared type of the value is a primitive type or >> java.lang.String, then the value is used directly (for strings, 0 means >> null and all other values are indices in the string table); in all other >> cases (including "primitive wrapper types" such as java.lang.Boolean or >> java.lang.Integer), the value will always start with its runtime type (or 0 >> if it's null). >> >> Assuming we're looking at the correct version of the sources, we'll >> indeed find, in order, commandId as a null Guid, commandType as the first >> constant of the ActionType enum (type = 5 = ActionType, followed by 0 = >> ordinal in the enum). The next 2 '0' would be compensationEnabled as a >> boolean false, and correlationId as a null String, respectively. >> Next would be endProcedure, as the the second (ordinal = 1) constant of >> the EndProcedure enum, i.e. PARENT_MANAGED; and so on and so on. >> >> The one thing that's not clear in the doc, is how to interpret negative >> values for objects (in place of the type or 0 for null, to reference an >> already deserialized object). I suppose that you could put each object into >> an array, and you'd use the absolute value as a 1-based index in that array. >> I see a -6 in the payload, but I have no idea at first glance whether >> it'll be a numeric value or a reference to an already-deserialized object. >> You have to go through the pipe-delimited fields one by one to know what >> each one means. >> >> >>> >>> вторник, 23 октября 2018 г., 13:26:06 UTC+3 пользователь Thomas Broyer >>> написал: >>>> >>>> On Tuesday, October 23, 2018 at 11:46:56 AM UTC+2, Anastasiya >>>> Ruzhanskaya wrote: >>>>> >>>>> Hello all! >>>>> I am working with oVirt (which helps to manage virtual machines) >>>>> project and it uses GWT RPC protocol in it's communications. >>>>> I want to parse messages in GWT RPC format which I get after >>>>> deciphering the traffic. >>>>> >>>>> I hope that even without being totally familiar with the ovirt >>>>> project, someone will be able to help me a little bit. >>>>> >>>>> I already separated it on some meaningful parts), numbers in braces >>>>> just help to make correspondence between payload and strings: >>>>> 7| >>>>> 0| >>>>> 14| >>>>> (1)https://engine.localdomain/ovirt-engine/webadmin/| //URL >>>>> (2)E8B2AD24442204349EF795039C3B87E5| // policy name >>>>> (3)org.ovirt.engine.ui.frontend.gwtservices.GenericApiGWTService| >>>>> //service interface >>>>> (4)runMultipleActions| //name of the method >>>>> (5)org.ovirt.engine.core.common.action.ActionType/12242454|, // type1 >>>>> (6)java.util.ArrayList/4159755760|, // type2 >>>>> (7)Z| // type3 (bool) >>>>> (8)org.ovirt.engine.core.common.action.ShutdownVmParameters/1694554255| >>>>> // class which contains uuid of the virtual machine >>>>> (9)org.ovirt.engine.core.compat.Guid/1992968158| >>>>> (10)java.util.UUID/2940008275| // seems the uuid of the virtual >>>>> machine) >>>>> >>>>> (11)org.ovirt.engine.core.common.action.ActionParametersBase$EndProcedure/1568822488| >>>>> (12)java.util.Collections$EmptyMap/4174664486| >>>>> (13)org.ovirt.engine.core.common.businessentities.VDSStatus/1938301532| >>>>> (14)org.ovirt.engine.core.compat.TransactionScopeOption/1475850853| >>>>> (the following is the payload separated and commented in places where >>>>> I can understand it) >>>>> 1| >>>>> 2| >>>>> 3| >>>>> 4| >>>>> 4|- 4 method parameters >>>>> 5|- first type = ActionType >>>>> 6|- second type = arraylist >>>>> 7|- third type = boolean >>>>> 7|- fourth type = boolean >>>>> 5(actionType)|9 (shutdown)| >>>>> 6(arrayList)|1(??)| >>>>> 8 (shutdown vm parameters, list object)|1|0|0|0|(??) >>>>> 9 (guid, ?)|10(UUID)|J$m4mk9wVi3|MjeP460Xkpb (vm >>>>> uuid)|0|5|0|0|0|11|1|0|6|0|0|0|0|0|0|12|0|-6|13|0|1|0|1|14|2|0|0|0|0|0| >>>>> >>>>> >>>>> Until virtual machine uuid parameter it is kind of clear what is >>>>> happening, but I still wonder what do the parameters 1 and 0 mean in >>>>> places >>>>> marked as (??). I understand, that there is a method called >>>>> runMultipleActions and it has four parameters. I found in source examples >>>>> of calling this method .Then I determine types of these parameters. Then >>>>> the type of action performed ( I shut down the machine). Then there >>>>> should >>>>> be an ArrayList, which contains several objects. I assume that 8(shutdown >>>>> vm parameters) should follow right after 6 (arraylist), but there a "1" >>>>> which I can't explain. Also I don't know what for are these four boolean >>>>> values (1|0|0|0) What do they mean? And how can I cope with the left >>>>> payload? >>>>> >>>>> This is the example of the call from ovirt source code: >>>>> >>>>> ArrayList<ActionParametersBase> parameters = new ArrayList<>(); >>>>> parameters.add(new ActionParametersBase()); >>>>> parameters.get(0).setCommandId(Guid.Empty); >>>>> parameters.add(new ActionParametersBase()); >>>>> frontend.runMultipleAction(ActionType.AddLocalStorageDomain, >>>>> parameters, false, mockMultipleActionCallback, >>>>> testState); >>>>> >>>>> >>>>> >>>>> Thank you in advance for any help! >>>>> >>>>> >>>>> I know this is kind of specific for oVirt but probably there is >>>>> something more that I should know about parsing the messages ( in the >>>>> internet I found a couple of articles about this, which helped me to >>>>> understand the first part of the message). >>>>> >>>> >>>> Fwiw, the GWT-RPC wire protocol is documented at >>>> https://docs.google.com/document/d/1eG0YocsYYbNAtivkLtcaiEE5IOF5u4LUol8-LL0TIKU/view >>>> >>>> The first value after the ArrayList runtime type is its length (see [1] >>>> and [2]). In this case, the list contains only one item. >>>> >>>> Then, according to the doc, the fields of the ShutdownVmParameters are >>>> serialized in alphabetical order, walking up the class hierarchy. So the >>>> first boolean would be ShutdownVmParameters#waitBeforeShutdown (boolean >>>> true), followed by StopVmParametersBase#stopReason (0 means null), >>>> then VmOperationParameterBase#quotaId (again a null), >>>> and VmOperationParameterBase#rerun (boolean false). >>>> This is then followed by VmOperationParameterBase#vmId, which is a >>>> Guid, itself having a single field of type UUID, which is serialized as a >>>> pair of longs by a UUID_CustomFieldSerializer [3], as you correctly >>>> identified. >>>> Following would be the ActionParametersBase [4] fields, followed by the >>>> last 2 method arguments. >>>> >>>> [1] >>>> https://github.com/gwtproject/gwt/blob/2.8.2/user/src/com/google/gwt/user/client/rpc/core/java/util/ArrayList_CustomFieldSerializerBase.java >>>> [2] >>>> https://github.com/gwtproject/gwt/blob/2.8.2/user/src/com/google/gwt/user/client/rpc/core/java/util/Collection_CustomFieldSerializerBase.java >>>> [3] >>>> https://github.com/oVirt/ovirt-engine/blob/60b63cf01dd46721afa269f1fbbc16d0ade2257b/frontend/webadmin/modules/gwt-extension/src/main/java/com/google/gwt/user/client/rpc/core/java/util/UUID_CustomFieldSerializer.java >>>> [4] >>>> https://github.com/oVirt/ovirt-engine/blob/60b63cf01dd46721afa269f1fbbc16d0ade2257b/backend/manager/modules/common/src/main/java/org/ovirt/engine/core/common/action/ActionParametersBase.java >>>> >>>> -- You received this message because you are subscribed to the Google Groups "GWT Users" group. 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