# HG changeset patch
# User Denis Laxalde <denis.laxalde@logilab.fr>
# Date 1554715493 -7200
# Node ID afafc8fd9a45fb4208a8207f127fb26253b56373
# Parent  2508ba96fad28e80c23871a901c495daa75729ee
Account for new psycopg2 exception classes mapping

From psycopg2 >= 2.8, specific exceptions are raised corresponding to
postgresql errors. E.g. a CheckViolation exception is raised instead of
a generic IntegrityError previously when a constraint violation occurs.
The way we intercept database errors, especially for constraint
violation, is not compliant with that because we do not catch subclasses
of IntegrityError in native source's doexec() method.

We fix this by checking for the presence of IntegrityError error in
exception class's mro. This is still overcomplicated and clumsy, because
we still use string comparison, but this is the best we can do as far as
I know. (A better fix would be 'isinstance(ex, IntegrityError)' but we
have no engine-independent error classes, so this is not possible.
Something like sqlalchemy's DBAPI Errors [1] might help:
https://docs.sqlalchemy.org/en/latest/errors.html#dbapi-errors)

diff -r 2508ba96fad2 -r afafc8fd9a45 cubicweb/server/sources/native.py
--- a/cubicweb/server/sources/native.py	Tue Apr 16 15:49:03 2019 +0200
+++ b/cubicweb/server/sources/native.py	Mon Apr 08 11:24:53 2019 +0200
@@ -695,7 +695,8 @@
                         self.debug('transaction has been rolled back')
                 except Exception:
                     pass
-            if ex.__class__.__name__ == 'IntegrityError':
+            if any(cls.__name__ for cls in ex.__class__.__mro__
+                   if cls.__name__ == 'IntegrityError'):
                 # need string comparison because of various backends
                 for arg in ex.args:
                     # postgres, sqlserver