Install "ironic" in the unittest environment

This patch is adding a helper script called "pip_install" to install
ironic in the unittests environment. This is needed because drivers will
import modules directly from Ironic (e.g the base driver interfaces,
exceptions)

Change-Id: I42ccbfde8f3381b9d77f85b3f676c0b455c62851

.gitignore

@@ -28,6 +28,7 @@ pip-log.txt
 nosetests.xml
 .testrepository
 .venv
+.test-tars
 
 # Translations
 *.mo

pip_install

@@ -0,0 +1,20 @@
+#!/bin/sh
+set -ex
+
+ZUUL_CLONER=/usr/zuul-env/bin/zuul-cloner
+
+mkdir -p .test-tars
+
+if $(python -c "import ironic" 2> /dev/null); then
+    echo "Ironic already installed."
+elif [ -x $ZUUL_CLONER ]; then
+    $ZUUL_CLONER --cache-dir /opt/git --workspace /tmp git://git.openstack.org openstack/ironic
+    pip install /tmp/openstack/ironic
+else
+    ( cd .test-tars && wget -N http://tarballs.openstack.org/ironic/ironic-master.tar.gz )
+    pip install .test-tars/ironic-master.tar.gz
+fi
+
+pip install -U $*
+
+exit $?

tox.ini

@@ -5,9 +5,7 @@ envlist = py34,py27,pep8
 
 [testenv]
 usedevelop = True
-install_command =
-                  constraints: pip install -U --force-reinstall -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
-                  pip install -U {opts} {packages}
+install_command = {toxinidir}/pip_install {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
          PYTHONDONTWRITEBYTECODE = 1
          LANGUAGE=en_US