Fix NaNs in JSON

metobsapi/data_api.py

@@ -160,6 +160,8 @@ def handle_csv(frame, epoch, sep=',',
 @as_json_p(optional=True)
 def handle_json(frame, epoch, order='columns',
                 message='', code=200, status='success', **kwargs):
+    # replace NaNs with None
+    frame = frame.where(pd.notnull(frame), None)
     output = {}
     output['status'] = status
     output['message'] = message

metobsapi/tests/test_data_api.py

@@ -20,6 +20,11 @@ def fake_data(interval, symbols, num_vals):
                 [(now + timedelta(minutes=i)).strftime(t_format)] + \
                 [random.random()] * (len(columns) - 1)
             )
+            # make up some Nones/nulls (but not all the time)
+            r_idx = int(random.random() * len(columns) * 3)
+            # don't include time (index 0)
+            if 0 < r_idx < len(columns):
+                vals[-1][r_idx] = None
         s = {
             'name': measurement_name,
             'columns': columns,