Further work on getting configurable service setup

snap/hooks/configure

@@ -1,12 +1,6 @@
 #!/bin/sh -e
 
-listen_port="$(snapctl get novncsvc.listen_port)"
-vnc_host_port="$(snapctl get novncsvc.vnc_host_port)"
+listen_port="$(snapctl get novncsvc.listen-port)"
+vnc_host_port="$(snapctl get novncsvc.vnc-host-port)"
 
- # Validate listen_port
-if ! expr "$listen_port" : '^[0-9]\+$' > /dev/null; then
-    echo "\"$listen_port\" is not a valid port number" >&2
-    return 1
-fi
-
-snapctl restart novncsvc
+snapctl restart novnc.novncsvc

snap/hooks/install

@@ -0,0 +1,5 @@
+#!/bin/sh -e
+
+# Initialise settings to blank default values so that novncsvc won't start unless the user sets these values to something meaningful
+snapctl set novncsvc.listen-port=0
+snapctl set novncsvc.vnc-host-port=''

snap/snapcraft.yaml

@@ -11,13 +11,14 @@ confinement: strict
 
 parts:
     novnc:
-        source: https://github.com/tkedwards/noVNC.git # https://github.com/novnc/noVNC.git #https://github.com/novnc/noVNC/archive/v$SNAPCRAFT_PROJECT_VERSION.tar.gz 
+        source: . #https://github.com/tkedwards/noVNC.git # https://github.com/novnc/noVNC.git #https://github.com/novnc/noVNC/archive/v$SNAPCRAFT_PROJECT_VERSION.tar.gz 
         plugin: dump
-        source-branch: snap_package
         stage-packages:
             - websockify
 
 hooks:
+    install:
+        plugs: [network, network-bind]
     configure:
         plugs: [network, network-bind]
 
@@ -27,5 +28,5 @@ apps:
         plugs: [network, network-bind]
     novncsvc:
         command: utils/svc_wrapper.sh
-        daemon: simple
+        daemon: forking
         plugs: [network, network-bind]

utils/svc_wrapper.sh

@@ -1,6 +1,13 @@
-#!/usr/bin/bash
+#!/usr/bin/env bash
 
-listen_port="$(snapctl get novncsvc.listen_port)"
-vnc_host_port="$(snapctl get novncsvc.vnc_host_port)"
+listen_port="$(snapctl get novncsvc.listen-port)"
+vnc_host_port="$(snapctl get novncsvc.vnc-host-port)"
 
-utils/launch.sh --listen $listen_port --vnc $vnc_host_port
+expr "$listen_port" : '^[0-9]\+$' > /dev/null
+listen_port_valid=$?
+if [ ! $listen_port_valid ] || [ -z "$vnc_host_port" ]; then
+    # invalid values mean the service is disabled, do nothing
+    echo "novncsvc disabled"
+else
+     ./utils/launch.sh --listen $listen_port --vnc $vnc_host_port
+fi