Re: Improve error handling in pltcl

On 3/3/16 8:51 AM, Pavel Stehule wrote:

Hi

I am testing behave, and some results looks strange

Thanks for the review!

postgres=# \sf foo
CREATE OR REPLACE FUNCTION public.foo()
  RETURNS void
  LANGUAGE plpgsql
AS $function$
begin
   raise exception sqlstate 'ZZ666' using message='hello, world',
detail='hello, my world', hint = 'dont afraid';
end
$function$

postgres=# select tcl_eval('spi_exec "select foo();"');
ERROR:  38000: hello, world
CONTEXT:  hello, world   <<<<==========???????

the message was in context. Probably it is out of scope of this patch,
but it isn't consistent with other PL


     while executing
"spi_exec "select foo();""
     ("eval" body line 1)
     invoked from within
"eval $1"
     (procedure "__PLTcl_proc_16864" line 3)
     invoked from within
"__PLTcl_proc_16864 {spi_exec "select foo();"}"
in PL/Tcl function "tcl_eval"
LOCATION:  throw_tcl_error, pltcl.c:1217
Time: 1.178 ms

Both problems actually exists in HEAD. The issue is this line in throw_tcl_error:

        econtext = utf_u2e(Tcl_GetVar(interp, "errorInfo", TCL_GLOBAL_ONLY));

Offhand I don't see any great way to improve that behavior, and in any case it seems out of scope for this patch. As a workaround I'm just forcing psql error VERBOSITY to terse for now.

postgres=# select tcl_eval('join $::errorCode "\n"');
                 tcl_eval
═════════════════════════════════════════
  POSTGRES                               ↵
  message                                ↵
  hello, world                           ↵
  detail                                 ↵
  hello, my world                        ↵
  hint                                   ↵
  dont afraid                            ↵
  domain                                 ↵
  plpgsql-9.6                            ↵
  context_domain                         ↵
  postgres-9.6                           ↵
  context                                ↵
  PL/pgSQL function foo() line 3 at RAISE↵
  SQL statement "select foo();"          ↵
  cursor_position                        ↵
  0                                      ↵
  filename                               ↵
  pl_exec.c                              ↵
  lineno                                 ↵
  3165                                   ↵
  funcname                               ↵
  exec_stmt_raise
(1 row)

I miss a SQLSTATE.

Great catch. Fixed.

Why is used List object instead dictionary? TCL supports it
https://www.tcl.tk/man/tcl8.5/tutorial/Tcl23a.html

Because errorCode unfortunately is an array and not a dict. It doesn't really seem worth messing with it in the eval since this is just a sanity check...

New patch attached. It also removes some other unstable output from the regression test.

--
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com