Assertion failure (uROAsync.pas, line 495)

Remoting SDK
,
1

Hi,

Just testing our latest software release and code that has been working successfully & is unchanged since RO v7 is now failing with:

Assertion failure ([…]\RemObjects Software\RemObjects SDK for Delphi\Source\uROAsync.pas, line 495)

Line 495 is in TROAsyncProxy.__RetrieveAsyncResponse and is:

Assert(Assigned(fResponse));

We’re using async calls to start long running DB processes on the server and using a Timer to poll for the results, which I believe is fairly standard stuff. It’s a custom Delphi server with a RODL, (i.e. not a code-first server).

The full bug report from MadExcept is here: http://pastebin.com/hMbqrBs8

Delphi 10.1 Berlin
RO SDK/DA 9.0.97.1245

Thanks,
Stuart

2

it can be happened if Retrieve_DependencyCalcsDateRange was called twice for the same request.

I can recommend to migrate to async requests via new *_AsyncEx interfaces
Usage of AsyncEx interfaces are demonstrated in the Phone Photo Server sample.

3

Thanks for the information but this would seem to be quite inconvenient to re-write code that was working.

What version of RO SDK was AsyncEx introduced?

I have customers with old server versions out there that this may not be compatible with & I need to not break anything.

Thanks.

4

AsyncEx interface this is client-only thing so it will be compatible with any server

5

HI,

Okay thanks, that’s good news.

I completed missed the news about Aysnc being broken and the new AsyncEx … was it published somewhere I’m not reading - or was it a release email that I might not have read properly?

Thank you
Stuart

6

it was announced two years ago as 66228: Improved async client APIs for Summer 2014 (8.0.81.1131).
New API uses the same mechanism as async calls in .NET

7

Thanks for the info.

Can you help me with the TROIndyHTTPChannel TimeOut property?

If I set this to 30000 (30s) then I get read timed out error 30s into the Async call.

Clearly I have to set this to -1 in order to allow Async calls to complete in their own time,
but will having Timeout=-1 have any undesirable side effects in the rest of the application?

Sorry, but I’m not very familiar with the indy components.

Thanks

8

-1 in case of Indy library mean to use default timeout.

Probably you need to set -2:

  IdTimeoutDefault = -1;
  IdTimeoutInfinite = -2;
9

Thanks Evgeny - very helpful.

One last question please (sorry).

In my code (which is very old) I create a duplicate Channel omponent for use with the Async calls - do I need to do that any more, or can I use the Channel component from fClientDataModule ?

Thanks

10

for AsyncEx calls - you can use existing one. for old Async calls, you need to duplicate channel.
of course, super channels also can use only one instance

11

Excellent - thanks.

I may keep the duplicate channel - it allows me to set the -2 Timeout :smile:

Thanks very much, Evgeny