After migrating to RO 10.0.0.1521 we have an issue with our dataabract (DA3) services.
Our client code searches for operations by name in the RODL library but now method ‘UpdateData’ is not found anymore. It looks like he does not find the ancestor of our “OffServerService” service which is a “DARemoteService” service.
The peculiar thing is that this all works fine on my development machines.
It even works between a client on my development machine and a RO server on a test machine.
But it does not work when both client and server is on the test machine.
A server built with the same source code and an older RO version works.
The newest RO version (1537) still fails. Both in XE10.4 and XE11.x
Our code to find which service hosts a function is:
lService := GetRODLLibraryThreadSafe(Service).FindService(Service.ServiceName); //RODLService;
repeat
if lService=nil then
ls().LogInfo(‘Service "’+Service.ServiceName+’" not found’)
else
ls().LogInfo(‘Service "’+lService.Name+’" found’);
lOperation := lService.Default.FindOperation(aRemoteRequest.MethodName);
if not Assigned(lOperation) then
begin
if lService.Ancestor <> ‘’ then
lService := GetRODLLibraryThreadSafe(Service).FindService(lService.Ancestor)
//if Assigned (lService) then
// lOperation := lService.Default.FindOperation(aRemoteRequest.MethodName);
else
lService := nil;
end;
until Assigned(lOperation) or (not Assigned(lService));
FYI: To support DA3 we have to make 2 changes RO
Copy dataabstract3.rodl from the legacy directory
Change remobjects.inc by defining {$DEFINE TROPROXY_IGNORES_REMOTESERVICE_SERVICENAME}
We come from 10.0.0.1495
I will mail the RODL (it is a rodl based delphi server)
It would take me a lot of time to write a testcase.
Do you need both server and client code?
Are there any known dependencies? XMl parser? I am baffled that it works on some machines.
I understood your issue - it can’t locate DataAbstract3.RODL on test machine because it hasn’t DAD installed.
what I can suggest:
consider to manually “detect” known members of IDARemoteService when DARemoteService ancestor is detected.
ship DataAbstract3.RODL & DataAbstract4.RODL with client and load it dynamically when needed. see examples how to load them manually at TXMLToRODL.LoadUses
Regarding 1:
You show me how I can detect it manually.
I was asking how I can detect it programmatically
Is there a way to rewrite our client code (shown below, I realise I can hardcode all my services):
lService := GetRODLLibraryThreadSafe(Service).FindService(Service.ServiceName); //RODLService;
repeat
if lService=nil then
ls().LogInfo(‘Service "’+Service.ServiceName+’" not found’)
else
ls().LogInfo(‘Service "’+lService.Name+’" found’);
lOperation := lService.Default.FindOperation(aRemoteRequest.MethodName);
if not Assigned(lOperation) then
begin
if lService.Ancestor <> ‘’ then
lService := GetRODLLibraryThreadSafe(Service).FindService(lService.Ancestor)
//if Assigned (lService) then
// lOperation := lService.Default.FindOperation(aRemoteRequest.MethodName);
else
lService := nil;
end;
until Assigned(lOperation) or (not Assigned(lService));
Regarding bug or no bug:
Can you confirm this worked in RO 10.0.0.1495 and not in build 1521?
Or did we do something wrong/different?
Is there something wrong with our client ancestor loop?
As I see it the API provides an ancestor property which is not correct (to be verified once i can debug)
if lService.Ancestor <> '' then begin
if lService.Ancestor = 'DARemoteService' then begin
// do something
end
...
end
I don’t see changes in generation of RODL for RODL-based services.
try to add {$UNDEF RO_RTTI_Support} and
{$UNDEF CodeFirst_Use_RODL_Uses} to RemObjects_user.inc. it may change something.
by some reasons, I can’t get generated RODL similar to your exportedrodl.rodl if I use OffServerLibrary.rodl as a main RODL for project…
btw, for security reasons, some companies disable server.ServeRODL , server.ServeInfoPage, etc properties in release mode because this can be considered as a security hole.
Our previous release to our customers was 1489, I am not sure if 1495 does or does not have this issue.
I have debugged te code and indeed the Ancestor property of our service is still correct. It is the TRORemoteService.GetRODLLibrary which does not load/return a service.
So I could bypass the issue for some known operations as you suggest.
Have you also moved the da3 rodl file? Maybe that’s why you cannot reproduce? Note: My tests now are with v1521
This is an internal RO service (LAN, not internet) I assume we needn’t worry about the security hole. However we have some HTTPS based internet RO services and I have been wondering about the security for these. I’ll leave that for another support issue.
We are using this code that searches for the RODL services to update the remote data adapter parameters in case different functions are used. Below you find the source code of the entire function.
I guess that means that your solution of detecting the ‘DARemoteService’ ancestor cannot be used?
We need to set the parameter list. How can we do this if we cannot load the RODL library?
procedure TOffBaseDATable.XLSRefreshParams (aRemoteRequest: TDARemoteRequest);
var
lOperation: TRODLOperation;
lService: TRODLService;
newparam:TDARemoteRequestParam;
//lParam: TDARemoteRequestParam;
lOldParams: TDARemoteRequestParams;
//lOperationParam: TRODLOperationParam;
i: Integer;
begin
if not Assigned (aRemoteRequest) then
Raise Exception.Create (SNoRemoteRequestParameterAssigned);
// if not Assigned (RemoteService) then
// Raise Exception.Create(SNoRemoteServiceAssigned);
// if RemoteService.ServiceName = '' then
// Raise Exception.Create (SServiceNamePropertyOf + RemoteService.Name + SIsEmpty);
// if RODLLibrary = nil then
// Raise Exception.Create (SRODLLibraryNotAssigned);
// if RODLService = nil then
// Raise Exception.Create (SRODLServiceNotAssigned);
(* KCV --- 3/08/2007 13:45:49 *)
// Loosely coupling
lService := GetRODLLibraryThreadSafe(Service).FindService(Service.ServiceName); //RODLService;
repeat
if lService=nil then
ls().LogInfo('Service "'+Service.ServiceName+'" not found')
else
ls().LogInfo('Service "'+lService.Name+'" found');
lOperation := lService.Default.FindOperation(aRemoteRequest.MethodName);
if not Assigned(lOperation) then
begin
if lService.Ancestor <> '' then
begin
if CompareText(lService.Ancestor,'DARemoteService')=0 then
begin
if aRemoteRequest.MethodName='UpdateData' then
Exit;
end;
lService := GetRODLLibraryThreadSafe(Service).FindService(lService.Ancestor)
end
else
begin
lService := nil;
end;
end;
until Assigned(lOperation) or (not Assigned(lService));
if not Assigned(lOperation) then
Raise Exception.Create(SMethod + aRemoteRequest.MethodName + SNotFoundInService);
// +
// RemoteService.ServiceName + SOrItsAnchestors);
lOldParams := TDARemoteRequestParams.Create(nil);
for i := 0 to (aRemoteRequest.Params.Count - 1) do
begin
with lOldParams.Add do
begin
Name := aRemoteRequest.Params[i].Name;
Value := aRemoteRequest.Params[i].Value;
end;
end;
aRemoteRequest.Params.Clear;
if (lOperation.Result<>NIL) then
begin
newparam := aRemoteRequest.Params.Add();
newparam.CopyRODLParam(lOperation.Result, TRUE, lOldParams);
end;
for i := 0 to (lOperation.Count - 1) do
begin
newparam := aRemoteRequest.Params.Add();
newparam.CopyRODLParam(lOperation.Items[i], TRUE, lOldParams);
end;
FreeAndNil(lOldParams);
// for i := 0 to (lOperation.Count - 1) do
// begin
// lParam := aRemoteRequest.Params.Add();
// lOperationParam := lOperation.Items[i];
// lParam.Name := lOperationParam.Name;
// lParam.ParamType := lOperationParam.Flag;
// lParam.DataType := StrToDataType(lOperationParam.DataType);
// end;
end;
Is this an intentional difference? Is this the reason why our code broke? If it is intentional/permanent, how should we dynamically update our remote data adapter parameters now based on custom specified operations? A solution where RODL files need to be shipped is not elegant, the cleanest solution IMO is where the server gives information about all of it’s operations (even the ones in the ancestors)
After installing RO we always copy DataAbstract3.RODL from source/legacy to source. At development time this sufficed (and at runtime/deployed everything worked also). Are you now saying this copy operation will not be needed in future versions of RO?
check uDARemoteDataAdapterRequests.pas unit.
each class (like TDAUpdateDataRequest) has 2 methods:
SetupDefaultRequestV3
SetupDefaultRequest
so you can initialize request w/o reading RODL just knowing ancestor (DA3 or DA4 DataService).
Note: RDA also has these methods (SetupDefaultRequestV3 and SetupDefaultRequest)
try to create a new project and add DA3 uses.
it will be referenced to $(Data Abstract for Delphi)\Source\Legacy\DataAbstract3.RODL.
so you shouldn’t copy DA3 RODL to other place
Do you have samples of how SetupDefaultRequestV3 can be used?
My attempt (see below) fails.
I will furthermore be needing a way to copy the values
How do I achieve what CopyRODLParam(lOperation.Result, TRUE, lOldParams); does?
I am guessing the old params are copied?
The documentation does not make myself wiser (TRORequestParam)
if lService.Ancestor <> '' then
begin
if CompareText(lService.Ancestor,'DARemoteService')=0 then
begin
if CompareText(aRemoteRequest.MethodName,'UpdateData')=0 then
begin
Assert(aRemoteRequest is TDAUpdateDataRequest);
if aRemoteRequest is TDAUpdateDataRequest then
TDAUpdateDataRequest(aRemoteRequest).SetupDefaultRequestV3();
Exit;
end;
if CompareText(aRemoteRequest.MethodName,'GetDatasetSchema')=0 then
begin
Assert(aRemoteRequest is TDAGetSchemaRequest);
if aRemoteRequest is TDAGetSchemaRequest then
TDAGetSchemaRequest(aRemoteRequest).SetupDefaultRequestV3();
Exit;
end;
end;
lService := GetRODLLibraryThreadSafe(Service).FindService(lService.Ancestor)
end
FYI: The code I posted does not work, call to
GetSchemaCall.ParamByName(‘aDataSetName’).Value := GetTableName;
throws an exception (the parameter is not found) but looking at uDARemoteDataAdapterRequest I indeed do not see ‘aDataSetName’ in TDAGetSchemaRequest
This is more or less what I do.
I am passing RemoteDataAdapter.GetSchemaCall to the function I posted (I have to cast the TRODynamicRequest to the actual type)
I think however the issue is the descrepancy betweenthe parameters in the IDARemoteService you posted above and the parameters in uDARemoteDataAdapterRequest (I do not see aDataSetName there)
Meanwhile I have specified
{$UNDEF RO_RTTI_Support}
{$UNDEF CodeFirst_Use_RODL_Uses}
in RemObjects_user.inc
but this does not change the behaviour. Should I do something after modifying this file?
I only did a full build of server and client.
