normalize errors, and use a global var for board manager...

I cannot figure out how to make this work w/ dep injection
due to needing to use asyncio to do DB accesses...  This will
work reliably, and is easy to understand...

bitelab/__init__.py

@@ -198,12 +198,31 @@ def get_data(settings: config.Settings = Depends(get_settings)):
 	d = make_orm(database)
 	return d
 
-@unhashable_lru()
-def sync_get_boardmanager(settings):
-	return BoardManager(settings)
+async def real_get_boardmanager(settings, data):
+	brdmgr = BoardManager(settings)
+
+	# Clean up the database
+	# XXX - This isn't a complete fix, we need a better solution.
+	all = await data.BoardStatus.objects.all()
+	await asyncio.gather(*(x.delete() for x in all))
+
+	return brdmgr
+
+_global_lock = asyncio.Lock()
+_global_brdmgr = None
+
+async def get_boardmanager(settings: config.Settings = Depends(get_settings),
+    data: data.DataWrapper = Depends(get_data)):
+	global _global_brdmgr
 
-async def get_boardmanager(settings: config.Settings = Depends(get_settings)):
-	return sync_get_boardmanager(settings)
+	if _global_brdmgr is not None:
+		return _global_brdmgr
+
+	async with _global_lock:
+		if _global_brdmgr is None:
+			_global_brdmgr = await real_get_boardmanager(settings, data)
+
+	return _global_brdmgr
 
 oauth2_scheme = OAuth2PasswordBearer(tokenUrl='/nonexistent')
 
@@ -231,7 +250,7 @@ async def validate_board_params(board_id, token, data, brdmgr):
 			brduser = await data.BoardStatus.objects.get(board=board_id)
 		except orm.exceptions.NoMatch:
 			raise BITEError(
-			    status_code=HTTP_403_FORBIDDEN,
+			    status_code=HTTP_400_BAD_REQUEST,
 			    errobj=Error(error='Board not reserved.',
 			    board=Board.from_orm(brd)))
 
@@ -750,8 +769,8 @@ class TestBiteLab(unittest.IsolatedAsyncioTestCase):
 		    auth=BiteAuth('thisisanapikey'),
 		    json=attrs)
 
-		# that it is forbidden
-		self.assertEqual(res.status_code, HTTP_403_FORBIDDEN)
+		# that it is a bad request
+		self.assertEqual(res.status_code, HTTP_400_BAD_REQUEST)
 
 		# that the cora-1 board is reserved
 		brd = self.brdmgr.boards['cora-1']