ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

larand54 · 2019-04-23 13:36:15

In unit mORMot:
procedure TCQRSService.InternalCqrsSetResult(Error: TCQRSResult; var Result: TCQRSResult);
procedure TJSONSerializer.WriteObject(Value: TObject; Options: TTextWriterWriteObjectOptions);

procedure WriteProp(P: PPropInfo);

Kind := P^.PropType^.Kind;
case Kind of <<<< Kind is 28 (TSQLRecordTableDeletedClass)
===== Raises exception External: SIGSEGV
tkInt64{$ifdef FPC}, tkQWord{$endif}: begin

This happends when I call the function ORMGetNextAggregate when there is no data left and when
it sets the cqrsStatus via InternalCqrsSetResult.

The code sequence in my testapp looks like:

    ticketServer.DBServer.Services.Resolve(IDomTicketCommand,IDTC);

    theTicket := TDTOTicket.Create;
    theTicket.ticketNo := 199;
    cqrsStatus := IDTC.Add(theTicket);
    IDTC.Commit;
    try
      cqrsStatus := IDTC.SelectAll;
      if cqrsStatus in [cqrsSuccess, cqrsSuccessWithMoreData] then begin
        while cqrsStatus in [cqrsSuccessWithMoreData, cqrsSuccess] do
        begin
          cqrsStatus := IDTC.getNext(theTicket);

What can I do here? Is it a system bug or am I the bug?

Last edited by larand54 (2019-05-05 11:43:29)

ab · 2019-04-23 13:47:23

There are only 26 items in TTextKind, so I don't see how 28 should be in PropType^.Kind.

How is the TDTOTicket class defined?

larand54 · 2019-04-23 14:06:32

As simple as this:

  TDTOTicket = class(TSQLRecord)
  protected
    fticketNo: integer; // TTicketNo
    fdescription: RawUTF8; // TDescription
    fdateCreated: TDateTime; // TDateTime
    fdateOpened: TDateTime; // TDateTime
    fdateSolved: TDateTime; // TDateTime
  published
    /// maps TTicket.ticketNo (TTicketNo)
    property ticketNo: integer read fticketNo write fticketNo;
    /// maps TTicket.description (TDescription)
    property description: RawUTF8 read fdescription write fdescription;
    /// maps TTicket.dateCreated
    property dateCreated: TDateTime read fdateCreated write fdateCreated;
    /// maps TTicket.dateOpened
    property dateOpened: TDateTime read fdateOpened write fdateOpened;
    /// maps TTicket.dateSolved
    property dateSolved: TDateTime read fdateSolved write fdateSolved;
  end;

The server is running in the same program as the client, to simplify testing.

The server looks like this:

constructor TTicketServer.create(const aObserver: IErrorObserver);
begin
  DBConnect(rseZeosMySQL, 'zdbc:mysql://localhost:3306', 'test_mormot', 'root', 'gT7Wqa96S');
  Model := CreateTicketModel;
  VirtualTableExternalRegister(Model, [TTicket], Props);
  DBServer := TSQLRestServerDB.Create(Model, true);     // true -> Authorization used
  try
    DBServer.CreateMissingTables;
    DBServer.ServiceContainer.InjectResolver([TInfraRepoTicketFactory.create(DBServer)], false);
    DBServer.ServiceDefine(TInfraRepoTicket, [IDomTicketCommand], sicClientDriven);
    httpServer := TSQLHttpServer.Create(PORT_NAME, [DBServer], '+', HTTP_DEFAULT_MODE);
    try
      httpServer.AccessControlAllowOrigin := '*'; // allow cross-site AJAX queries
      CodeHalted := true;
      while CodeHalted do begin
        Application.ProcessMessages;
        sleep(1000);
      end;
    finally
      httpServer.Free;
    end;
  finally
    DBServer.Free;
  end;
end;

TTicket is defined as:

  TTicket = class(TSQLRecord)
  private
    fTicketNo: TTicketNo;
    fDescription : TDescription;
    fDateCreated: TDateTime;
    fDateModified: TDateTime;
    fDateOpened: TDateTime;
    fDateSolved: TDateTime;
    fCategory: TTicketCategory;
    function getTicketID: TTicketID;
  published
    property ticketNo: TTicketNo read fTicketNo write fTicketNo;
    property description: TDescription read fDescription write fDescription;
    property dateCreated: TDateTime read fDateCreated write fDateCreated;
    property dateOpened: TDateTime read fDateOpened write fDateOpened;
    property dateSolved: TDateTime read fDateSolved write fDateSolved;
  end;

Last edited by larand54 (2019-04-23 20:56:08)

larand54 · 2019-04-26 09:41:37

Still not solved, I've no idea how to proceed.. Help needed.
Here it crashes: https://pastebin.com/0fxPPnEB

Last edited by larand54 (2019-05-01 10:14:54)

larand54 · 2019-05-02 09:39:07

Ok,
I'm using a Lazarus installation, installed by using fpcupDeluxe choosing the trunk version and got fpc-3.3.1 and Lazarus-2.1.0. I included mORMot in the installation.
I also installed ZEOS (7.2.4-stable build at 2018-03-25 11:08:27).

I also installed the latest WAMP-server to get MySQL together with a convenient environment.

To test that I could use MySQL and ZEOS in future programming I created a simple simple application to test all this.
First I had both server and client in the same application but later I splited it into one client and one server application but the result is the same.
It has no problem adding new records in the database table and it can also read them back without any problem. But,
if I want to read them all by using the function "ORMGetNextAggregate" I get all records delivered but at the end, when this function tries to read beyond the last record,
it gets the cqrsStatuscode=cqrsSuccessWithMoreData. So far so good but then it tries to create the JSON-message to be sent back to the client it goes wrong.
It looks like it doesn't know when to stop the process so it goes to far and get garbage data.
The "PPropInfo^PropType^.Kind the point outside it's buffer and returns a value to the TTextKind variable Kind that is outside its definition.

Maybe it can be in the function listed below:

function InternalClassProp(ClassType: TClass): PClassProp;
{$ifdef FPC}
begin
  with GetFPCTypeData(pointer(ClassType.ClassInfo))^ do
    result := AlignToPtr(@UnitName[ord(UnitName[0])+1]);
{$else}
{$ifdef PUREPASCAL}
var PTI: PTypeInfo;
begin // code is a bit abstract, but compiles very well
  PTI := PPointer(PtrInt(ClassType)+vmtTypeInfo)^;
  if PTI<>nil then // avoid GPF if no RTTI available for this class
    with PTI^, PClassType(@Name[ord(Name[0])+1])^ do
      result := PClassProp(@UnitName[ord(UnitName[0])+1]) else
    result := nil;
{$else}
asm // this code is the fastest possible
        mov     eax, [eax + vmtTypeInfo]
        test    eax, eax
        jz      @z // avoid GPF if no RTTI available for this class
        movzx   edx, byte ptr[eax].TTypeInfo.Name
        lea     eax, [eax + edx].TTypeInfo.Name[1]
        movzx   edx, byte ptr[eax].TClassType.UnitName
        lea     eax, [eax + edx].TClassType.UnitName[1].TClassProp
@z:
{$endif PUREPASCAL}
{$endif FPC}
end;

The delphi version returns NIL when it don't find the classtype but the fpc version just returns the result from: AlignToPtr(@UnitName[ord(UnitName[0])+1]);
I failed to check what this function ( or isn't it a function?) returns.

I'm totally stuck here and if I don't solve this soon, there is nothing more than to leave this project I'm afraid.
I have struggled for days trying to solve this but now I understand I can't get any further without help.

Last edited by larand54 (2019-05-02 09:43:56)

ab · 2019-05-03 07:26:52

It is difficult to find out what your problem is.
ORMGetNextAggregate() should not deserialize void items...

https://en.wikipedia.org/wiki/Minimal_working_example ?

Please don't put big extend of code in the forum - especially of the framework code - see https://synopse.info/forum/misc.php?action=rules

larand54 · 2019-05-03 08:41:32

An immedite answer here, I'm just try to debug the "TestSQL3" app. It fails with access violation and it seems to be in the same code part as in my app.
What's common is that when a call result in a cqrsStatus <> cqrsSuccess and it tries to create the JSON formatted response it crasches.
It is very hard for me to understand what's really happends here and I've been trying to find out by debugging. So far I have not find it.
It should be simple though to reproduce it by running TestSQL3 with the same FPC-compiler 3.3.1 as I use.
The first test that fails is this:

Check(service.StartEmailValidation(template,'toto','toto@toto .com')=cqrsDDDValidationFailed);

This test is made to give an error status and that causes the crasch.

Is it enough to put the code into paste.bin, all code in one file or...?

ab · 2019-05-03 08:52:50

I am not able to reproduce it here.
https://gist.github.com/synopse/975ec9f … 15ec8a835e

What is your FPC revision?

Verbose: Free Pascal Compiler version 3.3.1-r40491 [2019/03/25] for x86_64

There may be a transient bug in the trunk...

Try to follow https://synopse.info/files/html/Synopse … l#TITL_203 instructions.

larand54 · 2019-05-03 09:12:51

I got the same revision.. very strange when you can't reproduce it. Can it be something with Lazarus?

Free Pascal Compiler version 3.3.1-r41736 [2019/03/19] for x86_64

ab · 2019-05-03 14:04:59

It is not the same revision: we use r40491 and you have a more recent one, r41736.

Try to follow https://synopse.info/files/html/Synopse … l#TITL_203 instructions.

larand54 · 2019-05-05 11:42:28

I have now installed a new version of fpc and lazarus following your instructions.
And now the testSQLite3 and my testapp works as it should.
Easy solved but hard to find

mORMot Open Source

#1 2019-04-23 13:36:15

ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#2 2019-04-23 13:47:23

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#3 2019-04-23 14:06:32

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#4 2019-04-26 09:41:37

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#5 2019-05-02 09:39:07

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#6 2019-05-03 07:26:52

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#7 2019-05-03 08:41:32

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#8 2019-05-03 08:52:50

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#9 2019-05-03 09:12:51

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#10 2019-05-03 14:04:59

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

#11 2019-05-05 11:42:28

Re: ORM crashes when all data is read using ORMGetNextAggregate[SOLVED]

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