fix: Block certain requests during playback

Probably due to memory/stack overrun, some more involved web API
requests cause the system to hang if performed during playback. For now,
block these requests during playback.

Signed-off-by: Matthias Blankertz <matthias@blankertz.org>

software/src/app.py

@@ -58,6 +58,7 @@ class PlayerApp:
         self.mp3file = None
         self.volume_pos = 3
         self.paused = False
+        self.playing = False
         self.player.set_volume(VOLUME_CURVE[self.volume_pos])
         self._onIdle()
 
@@ -115,6 +116,9 @@ class PlayerApp:
             # Check again in a minute
             self.timer_manager.schedule(time.ticks_ms() + self.idle_timeout_ms, self.onIdleTimeout)
 
+    def is_playing(self) -> bool:
+        return self.playing
+
     def _set_playlist(self, tag: bytes):
         if self.playlist is not None:
             pos = self.player.stop()
@@ -176,7 +180,9 @@ class PlayerApp:
     def _onIdle(self):
         self.timer_manager.schedule(time.ticks_ms() + self.idle_timeout_ms, self.onIdleTimeout)
         self.leds.set_state(self.leds.IDLE)
+        self.playing = False
 
     def _onActive(self):
         self.timer_manager.cancel(self.onIdleTimeout)
         self.leds.set_state(self.leds.PLAYING)
+        self.playing = True

software/src/main.py

@@ -65,7 +65,6 @@ def run():
 
     # Wifi with default config
     setup_wifi()
-    start_webserver(config)
 
     # Setup MP3 player
     with SDContext(mosi=hwconfig.SD_DI, miso=hwconfig.SD_DO, sck=hwconfig.SD_SCK, ss=hwconfig.SD_CS,
@@ -96,6 +95,7 @@ def run():
                                     config=lambda _: config)
             the_app = app.PlayerApp(deps)
 
+            start_webserver(config, the_app)
             # Start
             asyncio.create_task(aiorepl.task({'timer_manager': TimerManager(),
                                               'app': the_app}))

software/src/webserver.py

@@ -10,12 +10,14 @@ from microdot import Microdot
 webapp = Microdot()
 server = None
 config = None
+app = None
 
 
-def start_webserver(config_):
-    global server, config
+def start_webserver(config_, app_):
+    global server, config, app
     server = asyncio.create_task(webapp.start_server(port=80))
     config = config_
+    app = app_
 
 
 @webapp.route('/')
@@ -50,6 +52,8 @@ async def config_get(request):
 
 @webapp.route('/api/v1/config', methods=['PUT'])
 async def config_put(request):
+    if app.is_playing():
+        return 503
     try:
         config.set_config(request.json)
     except ValueError as ex: