Allow testing of MySQL and PostgreSQL scenario locally

This leverage pifpaf to start MySQL or PostgreSQL temporarily and allow to test
provisioning directly without being on OpenStack CI by adding new tox
targets:

- py27-mysql
- py27-postgresql
- py34-mysql
- py34-postgresql
- py27-all
- py34-all

These targets will start MySQL or PostgreSQL before running the tests,
while exporting the connection string to $PIFPAF_URL. The `all' target
will start both MySQL and PostgreSQL and will run the tests against
these backends, plus SQLite.

Also, this patches add OS_TEST_DBAPI_ADMIN_CONNECTION to be allowed to
be passed through tox. This allows to run the opportunistic tests on a
more persistent pifpaf database, for example by running tox with:

$ eval `pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql`
$ echo $OS_TEST_DBAPI_ADMIN_CONNECTION
postgresql://localhost/postgres?host=/var/folders/7k/pwdhb_mj2cv4zyr0kyrlzjx40000gq/T/tmpMGqN8C&port=9824
$ tox -e py27
[…]
$ tox -e py34
[…]
$ kill $PIFPAF_PID

Change-Id: I1ee582e6f96e98378f02be79f4aaff0f447a062a
Depends-On: Id3e6b694bb186724517599cd9875ad80ceeee053

CONTRIBUTING.rst

@@ -59,4 +59,31 @@ For MySQL you can use the following commands::
  mysql> GRANT ALL PRIVILEGES ON * . * TO 'openstack_citest'@'localhost';
  mysql> FLUSH PRIVILEGES;
 
+Alternatively, you can use `pifpaf`_ to run the unit tests directly without
+setting up the database yourself. You still need to have the database software
+installed on your system. The following tox environments can be used::
+
+  tox -e py27-mysql
+  tox -e py27-postgresql
+  tox -e py34-mysql
+  tox -e py34-postgresql
+  tox -e py27-all
+  tox -e py34-all
+
+The database will be set up for you locally and temporarily on each run.
+
+Another way is to start `pifpaf` manually and use it to run the tests as you
+wish::
+
+  $ eval `pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql`
+  $ echo $OS_TEST_DBAPI_ADMIN_CONNECTION
+  postgresql://localhost/postgres?host=/var/folders/7k/pwdhb_mj2cv4zyr0kyrlzjx40000gq/T/tmpMGqN8C&port=9824
+  $ tox -e py27
+  […]
+  $ tox -e py34
+  […]
+  # Kill pifpaf once you're done
+  $ kill $PIFPAF_PID
+
 .. _wiki: https://wiki.openstack.org/wiki/Testing#Unit_Tests
+.. _pifpaf: https://github.com/jd/pifpaf

setup.cfg

@@ -48,6 +48,8 @@ test =
 fixtures =
   testresources>=0.2.4 # Apache-2.0/BSD
   testscenarios>=0.4 # Apache-2.0/BSD
+pifpaf =
+  pifpaf>=0.1.0
 
 [files]
 packages =

tools/run-pifpaf-tests.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -e
+# Replace mysql:// by mysql+pymysql:// and add sqlite
+export OS_TEST_DBAPI_ADMIN_CONNECTION="${OS_TEST_DBAPI_ADMIN_CONNECTION/#mysql:/mysql+pymysql:};sqlite://"
+echo $OS_TEST_DBAPI_ADMIN_CONNECTION
+tools/pretty_tox.sh $*
+TEST_EVENTLET=1 tools/pretty_tox.sh $*

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-minversion = 1.6
+minversion = 1.8
 envlist = py34,py27,pep8,pip-missing-reqs
 
 [testenv]
@@ -8,7 +8,9 @@ whitelist_externals = bash
 setenv =
    VIRTUAL_ENV={envdir}
 deps = .[test,fixtures,mysql,postgresql]
+    py{27,34}-{postgresql,mysql,all}: .[pifpaf]
 commands = bash tools/pretty_tox.sh '{posargs}'
+passenv = OS_TEST_DBAPI_ADMIN_CONNECTION
 
 [testenv:sqla_09]
 commands = pip install SQLAlchemy>=0.9.0,!=0.9.5,<1.0.0
@@ -19,6 +21,28 @@ commands =
     env TEST_EVENTLET=0 bash tools/pretty_tox.sh '{posargs}'
     env TEST_EVENTLET=1 bash tools/pretty_tox.sh '{posargs}'
 
+[testenv:py27-all]
+commands = pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run mysql -- pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql -- {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
+[testenv:py34-all]
+commands = pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run mysql -- pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql -- {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
+[testenv:py27-mysql]
+commands =
+    pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run mysql {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
+[testenv:py27-postgresql]
+commands =
+    pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
+[testenv:py34-mysql]
+commands =
+    pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run mysql {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
+[testenv:py34-postgresql]
+commands =
+    pifpaf -g OS_TEST_DBAPI_ADMIN_CONNECTION run postgresql {toxinidir}/tools/run-pifpaf-tests.sh {posargs}
+
 [testenv:mysql-python]
 deps = .[mysql-c,postgresql,test,fixtures]
 setenv =