fix creation of fifo

phytopi/camera/camera.py

@@ -11,7 +11,7 @@ from phytopi import db, models, app
 # map commands
 camera_cmds = {
     'start_timelapse': 'tl 1',
-    'stop_timelapse': 'tl 0',
+    'stop_timelapse': 'tl 0'
 }
 
 class CameraStatus(Enum):
@@ -31,13 +31,18 @@ class CameraWorker(object):
         self.status = CameraStatus.STOPPED
     
     def start(self):
-        # create FIFO
-        os.mkfifo(self.fifo)
-
         # check if process is already running
         if os.path.isfile(self.pidfile):
             with open(self.pidfile, 'r') as fh:
                 self.pid = int(fh.read())
+            self.status = CameraStatus.IDLE
+            return
+
+        # create FIFO, if not existent
+        try:
+            os.mkfifo(self.fifo)
+        except FileExistsError:
+            pass
 
         # if not, spawn new process and create pid file
         self.proc = subprocess.Popen([self.executable])