From b6496ba3d28d685547eac2891bfea5f4ae60e834 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Mon, 29 Sep 2014 17:33:53 -0400 Subject: [PATCH] - A revisit to this issue first patched in 0.9.5, apparently psycopg2's ``.closed`` accessor is not as reliable as we assumed, so we have added an explicit check for the exception messages "SSL SYSCALL error: Bad file descriptor" and "SSL SYSCALL error: EOF detected" when detecting an is-disconnect scenario. We will continue to consult psycopg2's connection.closed as a first check. fixes #3021 --- doc/build/changelog/changelog_09.rst | 13 +++++++++++++ lib/sqlalchemy/dialects/postgresql/psycopg2.py | 14 +++++++++----- 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/doc/build/changelog/changelog_09.rst b/doc/build/changelog/changelog_09.rst index 7c75996a4b..e5d6703e3a 100644 --- a/doc/build/changelog/changelog_09.rst +++ b/doc/build/changelog/changelog_09.rst @@ -13,6 +13,19 @@ .. changelog:: :version: 0.9.8 + .. change:: + :tags: bug, postgresql + :versions: 1.0.0 + :tickets: 3021 + + A revisit to this issue first patched in 0.9.5, apparently + psycopg2's ``.closed`` accessor is not as reliable as we assumed, + so we have added an explicit check for the exception messages + "SSL SYSCALL error: Bad file descriptor" and + "SSL SYSCALL error: EOF detected" when detecting an + is-disconnect scenario. We will continue to consult psycopg2's + connection.closed as a first check. + .. change:: :tags: bug, orm, engine :versions: 1.0.0 diff --git a/lib/sqlalchemy/dialects/postgresql/psycopg2.py b/lib/sqlalchemy/dialects/postgresql/psycopg2.py index e6450c97fa..9dfd53e228 100644 --- a/lib/sqlalchemy/dialects/postgresql/psycopg2.py +++ b/lib/sqlalchemy/dialects/postgresql/psycopg2.py @@ -512,12 +512,14 @@ class PGDialect_psycopg2(PGDialect): def is_disconnect(self, e, connection, cursor): if isinstance(e, self.dbapi.Error): # check the "closed" flag. this might not be - # present on old psycopg2 versions + # present on old psycopg2 versions. Also, + # this flag doesn't actually help in a lot of disconnect + # situations, so don't rely on it. if getattr(connection, 'closed', False): return True - # legacy checks based on strings. the "closed" check - # above most likely obviates the need for any of these. + # checks based on strings. in the case that .closed + # didn't cut it, fall back onto these. str_e = str(e).partition("\n")[0] for msg in [ # these error messages from libpq: interfaces/libpq/fe-misc.c @@ -534,8 +536,10 @@ class PGDialect_psycopg2(PGDialect): # not sure where this path is originally from, it may # be obsolete. It really says "losed", not "closed". 'losed the connection unexpectedly', - # this can occur in newer SSL - 'connection has been closed unexpectedly' + # these can occur in newer SSL + 'connection has been closed unexpectedly', + 'SSL SYSCALL error: Bad file descriptor', + 'SSL SYSCALL error: EOF detected', ]: idx = str_e.find(msg) if idx >= 0 and '"' not in str_e[:idx]: -- 2.47.2