Virtual environment groundwork

Introduce the tooling to build virtual environments.

* tools/build_venv.sh: build a venv
* introduce lib/stack to house functionality extracted from stack.sh that
  is needed in other places, such as Grenade; start with stack_install_service
  to wrap the venv install mechanics
* declare PROJECT_VENV array to track where project venvs should be installed
* create a venv for each project defined in PROJECT_VENV in stack_install_service()

Change-Id: I508588c0e2541b976dd94569d44b61dd2c35c01c

clean.sh

@@ -120,7 +120,7 @@ if [[ -n "$SCREEN_LOGDIR" ]] && [[ -d "$SCREEN_LOGDIR" ]]; then
 fi
 
 # Clean up venvs
-DIRS_TO_CLEAN="$WHEELHOUSE"
+DIRS_TO_CLEAN="$WHEELHOUSE ${PROJECT_VENV[@]}"
 rm -rf $DIRS_TO_CLEAN
 
 # Clean up files

inc/python

@@ -15,6 +15,13 @@ INC_PY_TRACE=$(set +o | grep xtrace)
 set +o xtrace
 
 
+# Global Config Variables
+
+# PROJECT_VENV contains the name of the virtual enviromnet for each
+# project.  A null value installs to the system Python directories.
+declare -A PROJECT_VENV
+
+
 # Python Functions
 # ================
 
@@ -105,7 +112,6 @@ function pip_install {
                 -r $test_req
         fi
     fi
-    $xtrace
 }
 
 # get version of a package from global requirements file

lib/stack

@@ -0,0 +1,29 @@
+#!/bin/bash
+#
+# lib/stack
+#
+# These functions are code snippets pulled out of stack.sh for easier
+# re-use by Grenade.  They can assume the same environment is available
+# as in the lower part of stack.sh, namely a valid stackrc has been sourced
+# as well as all of the lib/* files for the services have been sourced.
+#
+# For clarity, all functions declared here that came from ``stack.sh``
+# shall be named with the prefix ``stack_``.
+
+
+# Generic service install handles venv creation if confgured for service
+# stack_install_service service
+function stack_install_service {
+    local service=$1
+    if type install_${service} >/dev/null 2>&1; then
+        if [[ -n ${PROJECT_VENV[$service]:-} ]]; then
+            rm -rf ${PROJECT_VENV[$service]}
+            source tools/build_venv.sh ${PROJECT_VENV[$service]}
+            export PIP_VIRTUAL_ENV=${PROJECT_VENV[$service]:-}
+        fi
+        install_${service}
+        if [[ -n ${PROJECT_VENV[$service]:-} ]]; then
+            unset PIP_VIRTUAL_ENV
+        fi
+    fi
+}

stack.sh

@@ -94,6 +94,9 @@ source $TOP_DIR/functions
 # Import config functions
 source $TOP_DIR/lib/config
 
+# Import 'public' stack.sh functions
+source $TOP_DIR/lib/stack
+
 # Determine what system we are running on.  This provides ``os_VENDOR``,
 # ``os_RELEASE``, ``os_UPDATE``, ``os_PACKAGE``, ``os_CODENAME``
 # and ``DISTRO``
@@ -742,13 +745,13 @@ fi
 
 if is_service_enabled keystone; then
     if [ "$KEYSTONE_AUTH_HOST" == "$SERVICE_HOST" ]; then
-        install_keystone
+        stack_install_service keystone
         configure_keystone
     fi
 fi
 
 if is_service_enabled s-proxy; then
-    install_swift
+    stack_install_service swift
     configure_swift
 
     # swift3 middleware to provide S3 emulation to Swift
@@ -762,23 +765,23 @@ fi
 
 if is_service_enabled g-api n-api; then
     # image catalog service
-    install_glance
+    stack_install_service glance
     configure_glance
 fi
 
 if is_service_enabled cinder; then
-    install_cinder
+    stack_install_service cinder
     configure_cinder
 fi
 
 if is_service_enabled neutron; then
-    install_neutron
+    stack_install_service neutron
     install_neutron_third_party
 fi
 
 if is_service_enabled nova; then
     # compute service
-    install_nova
+    stack_install_service nova
     cleanup_nova
     configure_nova
 fi
@@ -787,19 +790,19 @@ if is_service_enabled horizon; then
     # django openstack_auth
     install_django_openstack_auth
     # dashboard
-    install_horizon
+    stack_install_service horizon
     configure_horizon
 fi
 
 if is_service_enabled ceilometer; then
     install_ceilometerclient
-    install_ceilometer
+    stack_install_service ceilometer
     echo_summary "Configuring Ceilometer"
     configure_ceilometer
 fi
 
 if is_service_enabled heat; then
-    install_heat
+    stack_install_service heat
     install_heat_other
     cleanup_heat
     configure_heat

tools/build_venv.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+#
+# **tools/build_venv.sh** - Build a Python Virtual Envirnment
+#
+# build_venv.sh venv-path [package [...]]
+#
+# Assumes:
+# - a useful pip is installed
+# - virtualenv will be installed by pip
+# - installs basic common prereq packages that require compilation
+#   to allow quick copying of resulting venv as a baseline
+
+
+VENV_DEST=${1:-.venv}
+shift
+
+MORE_PACKAGES="$@"
+
+# If TOP_DIR is set we're being sourced rather than running stand-alone
+# or in a sub-shell
+if [[ -z "$TOP_DIR" ]]; then
+
+    set -o errexit
+    set -o nounset
+
+    # Keep track of the devstack directory
+    TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
+    FILES=$TOP_DIR/files
+
+    # Import common functions
+    source $TOP_DIR/functions
+
+    GetDistro
+
+    source $TOP_DIR/stackrc
+
+    trap err_trap ERR
+
+fi
+
+# Exit on any errors so that errors don't compound
+function err_trap {
+    local r=$?
+    set +o xtrace
+
+    rm -rf $TMP_VENV_PATH
+
+    exit $r
+}
+
+# Build new venv
+virtualenv $VENV_DEST
+
+# Install modern pip
+$VENV_DEST/bin/pip install -U pip
+
+for pkg in ${MORE_PACKAGES}; do
+    pip_install_venv $VENV_DEST $pkg
+done