Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

edwinsn · 2014-07-29 08:04:12

Arnaud,

Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit, as shown below?

procedure TSQLRestServerDB.Commit(SessionID: cardinal=1);
begin
  inherited Commit(SessionID); // reset fTransactionActive + write all TSQLVirtualTableJSON
  try
    DB.Commit;
  except
    on ESQLite3Exception do
      ; // just catch exception
  end;
end;

I think there are many cases we need the flexibility of being able to catch the sqlite 3 exceptions and handle accordingly.

edwinsn · 2014-07-29 08:43:19

Found another place that also eats the sqlite errors silently:

TSQLRestServerDB.EngineExecute();
Begin
...
      {$ifdef WITHLOG}
      DB.Log.Log(sllError,'% for %',[E,aSQL],self);
      {$else}
      LogToTextFile('TSQLRestServerDB.EngineExecute: '+RawUTF8(E.Message)+#13#10+aSQL);
      {$endif}

...
end;

I think when withlog is not defined, just call raise, give our programs the chance to get the exact error and handle accordingly. Handling errors with exceptions, instead of IF statements, are a commonly accepted concept, IIRC.

ab · 2014-07-29 17:54:39

Both Commit and RollBack are procedures, so do not return any error boolean flag.
Perhaps it is an issue, but their execution is expected to continue.

EngineExecute returns an error boolean flag.

In all case, any Exception would be logged on the server side.

edwinsn · 2014-07-30 05:53:35

Arnaud,

Is there an option to get over the currently forced logging and let us handle the errors?

ab wrote:

Both Commit and RollBack are procedures, so do not return any error boolean flag.
Perhaps it is an issue, but their execution is expected to continue.
EngineExecute returns an error boolean flag.
In all case, any Exception would be logged on the server side.

ab · 2014-07-30 07:49:48

edwinsn wrote:

Is there an option to get over the currently forced logging and let us handle the errors?

Not at TSQLRest level.
Just at SynSQlite3 level.

edwinsn · 2014-07-30 10:17:43

ab wrote:

edwinsn wrote:
Is there an option to get over the currently forced logging and let us handle the errors?
Not at TSQLRest level.
Just at SynSQlite3 level.

So would you accept this as an option to disabled the logging and let us handle exceptions, at TSQLRest level?

ab · 2014-07-30 11:57:32

This would be a breaking change of all TSQLRest interfaces behavior.
So I do not think it is suitable nor urgent.

edwinsn · 2014-07-30 15:05:20

Ok. So with the current implementation, what do you think to be the best way of getting the real sqlitedb errors? Like this?

if myRestServer.Add(...) < 1 then
beign
  GetTheLatestServerLogEntry() //how?
end

How? Your help will be appreciated!

Last edited by edwinsn (2014-07-30 15:05:47)

ab · 2014-07-30 17:28:17

Sadly, in a multi-threaded server, and even more from a remote client, such a pattern would not work.

You can't be sure that there won't be any other error between the Add() and the GetTheLatestServerLogEntry().

edwinsn · 2014-07-31 04:05:10

Arnaud,

I am not limited to the last server log entry, what I want is to get notified when there is a database error and know where to look for the error messages that really tell the true problem.

mORMot Open Source

#1 2014-07-29 08:04:12

Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#2 2014-07-29 08:43:19

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#3 2014-07-29 17:54:39

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#4 2014-07-30 05:53:35

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#5 2014-07-30 07:49:48

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#6 2014-07-30 10:17:43

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#7 2014-07-30 11:57:32

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#8 2014-07-30 15:05:20

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#9 2014-07-30 17:28:17

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

#10 2014-07-31 04:05:10

Re: Why the sqlite3 exceptions are eaten in TSQLRestServerDB.Commit?

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