fix: ensure cloned/renamed apps have a link to linked services

Previously they would just 'disappear', resulting in broken applications until the app was relinked to the service in question.

Closes dokku/dokku-redis#142

common-functions

@@ -4,6 +4,18 @@ set -eo pipefail
 [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_AVAILABLE_PATH/config/functions"
 
+add_to_links_file() {
+  declare desc="add an app to the service link file"
+  declare SERVICE="$1" APP="$2"
+  local SERVICE_ROOT="$PLUGIN_DATA_ROOT/$SERVICE"
+  local LINKS_FILE="$SERVICE_ROOT/LINKS"
+
+  touch "$LINKS_FILE"
+  sed -i.bak "/^$APP\$/d" "$LINKS_FILE" && rm "$LINKS_FILE.bak"
+  echo "$APP" >>"$LINKS_FILE"
+  sort "$LINKS_FILE" -u -o "$LINKS_FILE"
+}
+
 docker_ports_options() {
   declare desc="export a list of exposed ports"
   declare PORTS=("$@")
@@ -61,6 +73,15 @@ get_url_from_config() {
   echo "$EXISTING_CONFIG" | grep "$CONFIG_VAR" | sed "s/$CONFIG_VAR:\s*//" | xargs
 }
 
+in_links_file() {
+  declare desc="check if a service LINKS file contains an app"
+  declare SERVICE="$1" APP="$2"
+  local SERVICE_ROOT="$PLUGIN_DATA_ROOT/$SERVICE"
+  local LINKS_FILE="$SERVICE_ROOT/LINKS"
+
+  grep -qE "^$APP\$" "$LINKS_FILE"
+}
+
 is_container_status() {
   declare desc="return 0 or 1 depending upon whether a given container has a certain status"
   declare CID="$1" STATUS="$2"
@@ -501,9 +522,7 @@ service_link() {
 
   [[ -n $LINK ]] && dokku_log_fail "Already linked as $LINK"
   plugn trigger service-action pre-link "$SERVICE" "$APP"
-  touch "$LINKS_FILE"
-  echo "$APP" >>"$LINKS_FILE"
-  sort "$LINKS_FILE" -u -o "$LINKS_FILE"
+  add_to_links_file "$SERVICE" "$APP"
 
   if declare -f -F add_passed_docker_option >/dev/null; then
     # shellcheck disable=SC2034

post-app-clone-setup

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/config"
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/common-functions"
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/functions"
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
+
+plugin-post-app-clone-setup() {
+  declare OLD_APP_NAME="$1" NEW_APP_NAME="$2"
+
+  local SERVICES=$(ls "$PLUGIN_DATA_ROOT" 2>/dev/null)
+  for SERVICE in $SERVICES; do
+    if in_links_file "$SERVICE" "$OLD_APP_NAME"; then
+      add_to_links_file "$SERVICE" "$NEW_APP_NAME"
+    fi
+  done
+}
+
+plugin-post-app-clone-setup "$@"

post-app-rename-setup

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/config"
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/common-functions"
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/functions"
+set -eo pipefail
+[[ $DOKKU_TRACE ]] && set -x
+
+plugin-post-app-rename-setup() {
+  declare OLD_APP_NAME="$1" NEW_APP_NAME="$2"
+
+  local SERVICES=$(ls "$PLUGIN_DATA_ROOT" 2>/dev/null)
+  for SERVICE in $SERVICES; do
+    if in_links_file "$SERVICE" "$OLD_APP_NAME"; then
+      add_to_links_file "$SERVICE" "$NEW_APP_NAME"
+    fi
+  done
+}
+
+plugin-post-app-rename-setup "$@"