add knob for OPAE install

Currently, OPAE is so picky about the OS.

Not every developer need OPAE.
In order to make them happy, add knot for OPAE install.

Change-Id: Ief2c75c4bc80bb7b01a812fd6f18abd6a3acfcc5

devstack/lib/opae

@@ -21,7 +21,6 @@ function setup_distro_vars {
         [[ $os_RELEASE == "16.04" ]] && PKG_EXT="deb"
     fi
 }
-setup_distro_vars
 
 function install_opae_pkg {
     local pkg=$1
@@ -46,6 +45,7 @@ function install_opae_pkg {
 }
 
 function install_opae_packages {
+    setup_distro_vars
     local libs_url="$OPAE_GITHUB/$OPAE_LIBS.$PKG_EXT"
     local devel_url="$OPAE_GITHUB/$OPAE_DEVEL.$PKG_EXT"
 

devstack/plugin.sh

@@ -14,9 +14,9 @@ if is_service_enabled cyborg-api cyborg-cond; then
         # stack/pre-install - Called after (OS) setup is complete and before
         # project source is installed
             echo_summary "Installing additional Cyborg packages"
-            if install_opae_packages; then
+            if [[ "$OPAE_INSTALL_ENABLE" == "True" ]] && install_opae_packages; then
                echo_summary "INFO: Additional Cyborg packages installed"
-            else
+            elif [[ "$OPAE_INSTALL_ENABLE" == "True" ]]; then
                echo "WARNING: Failed to install additional Cyborg packages"
             fi
         elif [[ "$2" == "install" ]]; then
@@ -56,6 +56,8 @@ if is_service_enabled cyborg-api cyborg-cond; then
     # clean - Called by clean.sh before other services are cleaned, but after
     # unstack.sh has been called.
         cleanup_cyborg
+        if [[ "$OPAE_INSTALL_ENABLE" == "True" ]]; then
             uninstall_opae_packages
         fi
+    fi
 fi

devstack/settings

@@ -3,6 +3,7 @@ enable_service cyborg cyborg-api cyborg-cond cyborg-agent
 # OPAE settings
 # OPAE packages are not yet upstreamed into OS repos
 # We need to download them from OPAE releases page on GitHub
+OPAE_INSTALL_ENABLE=$(trueorfalse True OPAE_INSTALL_ENABLE)
 OPAE_VERSION=${OPAE_VERSION:-"1.1.0-2"}
 OPAE_GITHUB=${OPAE_GITHUB:-"https://github.com/OPAE/opae-sdk/releases/download/$OPAE_VERSION"}
 OPAE_DEVEL_PKG=${OPAE_DEVEL_PKG:-"opae-devel"}

doc/source/contributor/devstack_setup.rst

@@ -123,6 +123,25 @@ Enable services
 
   If you got version conflicts, please set `PIP_UPGRADE` to `True` in local.conf
 
+Disable OPAE install
+>>>>>>>>>>>>>>>>>>>>
+
+::
+
+  OPAE_INSTALL_ENABLE=false
+
+- By default OPAE_INSTALL_ENABLE is True.
+
+- You need to set OPAE_INSTALL_ENABLE as false explicitly,
+  if not need OPEA enviroment.
+
+- At present OPAE depends on OS verson heavily.
+
+.. note::
+
+  If you do not want to try Intel FPGA, you can disable OPAE install. Then you
+  do not depend on specific OS verson.
+
 
 Run DevStack
 ------------