Keep a fresh copy of apps.json

Ref #132

abra

@@ -6,6 +6,7 @@ ABRA_VERSION="0.6.0"
 ABRA_BACKUP_DIR="${ABRA_BACKUP_DIR:-$ABRA_DIR/backups}"
 ABRA_VENDOR_DIR="$ABRA_DIR/vendor"
 YQ="$ABRA_VENDOR_DIR/yq"
+ABRA_APPS_JSON="${ABRA_DIR}/apps.json"
 
 #######################################
 # Global help
@@ -434,7 +435,29 @@ require_consent_for_update() {
   fi
 }
 
-require_plugin (){
+require_apps_json() {
+  # Ensure we have the latest copy of apps.json
+  apps_url="https://abra-apps.cloud.autonomic.zone"
+  if [ -f "$ABRA_APPS_JSON" ]; then
+    modified=$(curl --silent --head $apps_url | \
+             awk '/^Last-Modified/{print $0}' | \
+             sed 's/^Last-Modified: //')
+    remote_ctime=$(date --date="$modified" +%s)
+    local_ctime=$(stat -c %Z "$ABRA_APPS_JSON")
+
+    if [ "$local_ctime" -lt "$remote_ctime" ]; then
+      info "Downloading new apps.json"
+      wget -qO "$ABRA_APPS_JSON" $apps_url
+    else
+      debug "No apps.json update needed"
+    fi
+  else
+    info "Downloading apps.json"
+    wget -qO "$ABRA_APPS_JSON" $apps_url
+  fi
+}
+
+require_plugin() {
   PLUGIN="$1"
 
   BRANCH="${abra___branch:-master}"
@@ -501,32 +524,42 @@ require_app_latest() {
   fi
 }
 
-require_yq() {
+vendor_binary() {
   require_vendor_dir
   require_binary wget
 
-  YQ_VERSION="4.6.1"
-  YQ_BINARY="yq_linux_amd64"
-  YQ_RELEASE_URL="https://github.com/mikefarah/yq/releases/download/v${YQ_VERSION}/${YQ_BINARY}"
+  local REPO="$1"
+  local VERSION="$2"
+  local FILE="$3"
+  local BINARY="${REPO##*/}"
+  local RELEASE_URL="$REPO/releases/download/${VERSION}/${FILE}"
 
-  if [ -f "$YQ" ]; then
-    debug "yq is already vendored"
+  if [ -f "$ABRA_DIR/vendor/$BINARY" ]; then
+    debug "$BINARY is already vendored"
     return
   fi
 
   case $(uname -m) in
     x86_64)
-      warning "Attempting to download the yq binary into $ABRA_VENDOR_DIR"
-      wget -q "$YQ_RELEASE_URL" && chmod +x "$YQ_BINARY" && mv "$YQ_BINARY" "$YQ"
-      success "yq is now vendored ☮"
+      warning "Attempting to download the $BINARY binary from $RELEASE_URL into $ABRA_VENDOR_DIR"
+      wget -qO "$ABRA_VENDOR_DIR/$BINARY" "$RELEASE_URL" && chmod +x "$ABRA_VENDOR_DIR/$BINARY" 
+      success "$BINARY is now vendored ☮"
       ;;
     *)
-      error "Unable to automatically vendor yq, you'll have to manually manage this\n
-       Please see https://mikefarah.gitbook.io/yq/#install and place the yq binary in the $YQ path"
+      error "Unable to automatically vendor $BINARY, you'll have to manually manage this.\n
+       Please see $REPO and place the $BINARY binary in $ABRA_VENDOR_DIR."
       ;;
   esac
 }
 
+require_jq() {
+  vendor_binary "https://github.com/stedolan/jq/" "jq-1.6" "jq-linux64"
+}
+
+require_yq() {
+  vendor_binary "https://github.com/mikefarah/yq" "v4.6.1" "yq_linux_amd64"
+}
+
 require_docker_version (){
   get_servers
 
@@ -2039,6 +2072,7 @@ abra() {
   if [ -n "$abra__app_" ]; then
     load_instance
     load_instance_env
+    require_apps_json
   fi
 
   load_abra_sh