Plugins management

We had an issue with third party plugins installing things via apt while
already installing dokku itself via apt.

To resolve this, `plugins-install` and `plugins-install-dependencies`
now can take a `--core` flag allowing to execute the install hook only
on core plugins and not on third party plugins.

Another feature with this modification is the ability to disable/enable
plugins. Two new commands now exist:

* `plugins:enable <name>` to enable a previously disabled plugin
* `plugins:disable <name>` to disable an installed plugin. This won’t
  work on core plugins.

Makefile

@@ -4,7 +4,10 @@ SSHCOMMAND_URL ?= https://raw.github.com/progrium/sshcommand/master/sshcommand
 PLUGINHOOK_URL ?= https://s3.amazonaws.com/progrium-pluginhook/pluginhook_0.1.0_amd64.deb
 STACK_URL ?= https://github.com/gliderlabs/herokuish.git
 PREBUILT_STACK_URL ?= gliderlabs/herokuish:latest
-PLUGINS_PATH ?= /var/lib/dokku/plugins
+DOKKU_LIB_ROOT ?= /var/lib/dokku
+PLUGINS_PATH ?= ${DOKKU_LIB_ROOT}/plugins
+CORE_PLUGINS_PATH ?= ${DOKKU_LIB_ROOT}/core-plugins
+DISABLED_PLUGINS_PATH ?= ${DOKKU_LIB_ROOT}/disabled-plugins
 
 # If the first argument is "vagrant-dokku"...
 ifeq (vagrant-dokku,$(firstword $(MAKECMDGOALS)))
@@ -44,13 +47,15 @@ packer:
 
 copyfiles:
 	cp dokku /usr/local/bin/dokku
-	mkdir -p ${PLUGINS_PATH}
+	mkdir -p ${CORE_PLUGINS_PATH} ${PLUGINS_PATH} ${DISABLED_PLUGINS_PATH}
-	find ${PLUGINS_PATH} -mindepth 2 -maxdepth 2 -name '.core' -printf '%h\0' | xargs -0 rm -Rf
+	rm -rf ${CORE_PLUGINS_PATH}/*
 	find plugins/ -mindepth 1 -maxdepth 1 -type d -printf '%f\n' | while read plugin; do \
-		rm -Rf ${PLUGINS_PATH}/$$plugin && \
+		rm -Rf ${CORE_PLUGINS_PATH}/$$plugin && \
-		cp -R plugins/$$plugin ${PLUGINS_PATH} && \
+		rm -rf ${PLUGINS_PATH}/$$plugin && \
-		touch ${PLUGINS_PATH}/$$plugin/.core; \
+		cp -R plugins/$$plugin ${CORE_PLUGINS_PATH} && \
+		ln -s ${CORE_PLUGINS_PATH}/$$plugin ${PLUGINS_PATH}; \
 		done
+	chown dokku:dokku -R ${PLUGINS_PATH} ${CORE_PLUGINS_PATH} ${DISABLED_PLUGINS_PATH}
 	$(MAKE) addman
 
 addman:
@@ -62,10 +67,10 @@ version:
 	git describe --tags > ~dokku/VERSION  2> /dev/null || echo '~${DOKKU_VERSION} ($(shell date -uIminutes))' > ~dokku/VERSION
 
 plugin-dependencies: pluginhook
-	dokku plugins-install-dependencies
+	dokku plugins-install-dependencies --core
 
 plugins: pluginhook docker
-	dokku plugins-install
+	dokku plugins-install --core
 
 dependencies: apt-update sshcommand pluginhook docker help2man man-db
 	$(MAKE) -e stack

debian/postinst

@@ -16,7 +16,7 @@ case "$1" in
     sshcommand create dokku /usr/local/bin/dokku
     egrep -i "^docker" /etc/group || groupadd docker
     usermod -aG docker dokku
-    dokku plugins-install
+    dokku plugins-install --core
     rm -f /home/dokku/VERSION
     cp /var/lib/dokku/STABLE_VERSION /home/dokku/VERSION
 

dokku

@@ -5,8 +5,11 @@ shopt -s nullglob
 export DOKKU_DISTRO=${DOKKU_DISTRO:="ubuntu"}
 export DOKKU_IMAGE=${DOKKU_IMAGE:="gliderlabs/herokuish"}
 export DOKKU_ROOT=${DOKKU_ROOT:=~dokku}
+export DOKKU_LIB_ROOT=${DOKKU_LIB_PATH:="/var/lib/dokku"}
 
-export PLUGIN_PATH=${PLUGIN_PATH:="/var/lib/dokku/plugins"}
+export PLUGIN_PATH=${PLUGIN_PATH:="$DOKKU_LIB_ROOT/plugins"}
+export PLUGIN_CORE_PATH=${PLUGIN_CORE_PATH:="$DOKKU_LIB_ROOT/core-plugins"}
+export PLUGIN_DISABLED_PATH=${PLUGIN_DISABLED_PATH:="$DOKKU_LIB_ROOT/disabled-plugins"}
 export DOKKU_NOT_IMPLEMENTED_EXIT=10
 export DOKKU_VALID_EXIT=0
 
@@ -199,14 +202,22 @@ case "$1" in
     ;;
 
   plugins)
-    ls -1 -d $PLUGIN_PATH/*/
+    for plugin in "$PLUGIN_PATH"/*/; do
+      basename "$plugin"
+    done
     ;;
 
   plugins-install)
+    if [[ $2 == "--core" ]]; then
+      export PLUGIN_PATH="$PLUGIN_CORE_PATH"
+    fi
     pluginhook install
     ;;
 
   plugins-install-dependencies)
+    if [[ $2 == "--core" ]]; then
+      export PLUGIN_PATH="$PLUGIN_CORE_PATH"
+    fi
     pluginhook dependencies
     ;;
 
@@ -214,6 +225,23 @@ case "$1" in
     pluginhook update
     ;;
 
+  plugins:disable)
+    PLUGIN="$2"
+    [[ -e $PLUGIN_CORE_PATH/$PLUGIN ]] && echo "Cannot disable a core plugin" && exit 1
+    [[ -e $PLUGIN_DISABLED_PATH/$PLUGIN ]] && echo "Plugin already disabled" && exit 1
+    [[ ! -e $PLUGIN_PATH/$PLUGIN ]] && echo "Plugin does not exist" && exit 1
+    mv "$PLUGIN_PATH/$PLUGIN" "$PLUGIN_DISABLED_PATH"
+    echo "Plugin $PLUGIN disabled"
+    ;;
+
+  plugins:enable)
+    PLUGIN="$2"
+    [[ -e $PLUGIN_PATH/$PLUGIN ]] && echo "Plugin already enabled" && exit 1
+    [[ ! -e $PLUGIN_DISABLED_PATH/$PLUGIN ]] && echo "Plugin does not exist" && exit 1
+    mv "$PLUGIN_DISABLED_PATH/$PLUGIN" "$PLUGIN_PATH"
+    echo "Plugin $PLUGIN enabled"
+    ;;
+
   # DEPRECATED as of v0.3.14
   deploy:all)
       echo "*DEPRECATED* in v0.3.14: deploy:all will be removed in future versions"
@@ -228,8 +256,11 @@ case "$1" in
     cat<<EOF | pluginhook commands help | sort | column -c2 -t -s,
     help, Print the list of commands
     plugins, Print active plugins
-    plugins-install, Install active plugins
+    plugins-install [--core], Install active plugins (or only core ones)
+    plugins-install-dependencies [--core], Install active plugins dependencies (or only core ones)
     plugins-update, Update active plugins
+    plugins:enable <name>, Enable a previously disabled plugin
+    plugins:disable <name>, Disable an installed plugin (third-party only)
 EOF
     ;;