Provision on different drivers dynamically

We want TOX_POSTGRESQL and similar to be the fixed variable
that is configured from CI environment.   These variables should refer
to database servers but individual drivers like asyncpg mysqlconnector
etc. should come from local tox.ini.  add a new system to generate
per-driver URLs from a simple list of hostname-based URLs delivered
from CI environment.

Change-Id: I4267b4a70742765388c7e7c4432c1da9d9adece2

1 files changed, 23 insertions, 2 deletions

diff --git a/lib/sqlalchemy/testing/plugin/plugin_base.py b/lib/sqlalchemy/testing/plugin/plugin_base.py
index 49ff0f975..b5f2a3e0b 100644
--- a/lib/sqlalchemy/testing/plugin/plugin_base.py
+++ b/lib/sqlalchemy/testing/plugin/plugin_base.py
@@ -17,10 +17,14 @@ is pytest.
 from __future__ import absolute_import
 
 import abc
+import logging
 import re
 import sys
 
 
+log = logging.getLogger("sqlalchemy.testing.plugin_base")
+
+
 py3k = sys.version_info >= (3, 0)
 
 if py3k:
@@ -91,6 +95,15 @@ def setup_options(make_option):
         help="Database uri.  Multiple OK, " "first one is run by default.",
     )
     make_option(
+        "--dbdriver",
+        action="append",
+        type="string",
+        dest="dbdriver",
+        help="Additional database drivers to include in tests.  "
+        "These are linked to the existing database URLs by the "
+        "provisioning system.",
+    )
+    make_option(
         "--dropfirst",
         action="store_true",
         dest="dropfirst",
@@ -350,6 +363,7 @@ def _init_symbols(options, file_config):
 
 @post
 def _engine_uri(options, file_config):
+
     from sqlalchemy.testing import config
     from sqlalchemy import testing
     from sqlalchemy.testing import provision
@@ -359,6 +373,8 @@ def _engine_uri(options, file_config):
     else:
         db_urls = []
 
+    extra_drivers = options.dbdriver or []
+
     if options.db:
         for db_token in options.db:
             for db in re.split(r"[,\s]+", db_token):
@@ -374,7 +390,11 @@ def _engine_uri(options, file_config):
         db_urls.append(file_config.get("db", "default"))
 
     config._current = None
-    for db_url in db_urls:
+
+    expanded_urls = list(provision.generate_db_urls(db_urls, extra_drivers))
+
+    for db_url in expanded_urls:
+        log.info("Adding database URL: %s", db_url)
 
         if options.write_idents and provision.FOLLOWER_IDENT:  # != 'master':
             with open(options.write_idents, "a") as file_:
@@ -596,7 +616,8 @@ def stop_test_class(cls):
 
 
 def _restore_engine():
-    config._current.reset(testing)
+    if config._current:
+        config._current.reset(testing)
 
 
 def final_process_cleanup():