From e1a3854f2a4ce44ea14a66796a0a53ca57f2b537 Mon Sep 17 00:00:00 2001
From: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>
Date: Fri, 20 May 2016 20:10:29 +0200
Subject: [PATCH] utils: add special serializer for numpy.int64 (#492)

It looks like COUNT(*) returns a numpy.int64 value that the
default JSONEncoder does not handle.

While at if we get a type we are not handling make it easier to
debug the issue by throwing a TypeError exception with useful
data.

Fix #486
---
 caravel/utils.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/caravel/utils.py b/caravel/utils.py
index 7e3d4c079f500..5f2a76009204e 100644
--- a/caravel/utils.py
+++ b/caravel/utils.py
@@ -7,6 +7,7 @@
 import functools
 import json
 import logging
+import numpy
 from datetime import datetime
 
 import parsedatetime
@@ -221,6 +222,12 @@ def json_iso_dttm_ser(obj):
     """
     if isinstance(obj, datetime):
         obj = obj.isoformat()
+    elif isinstance(obj, numpy.int64):
+        obj = int(obj)
+    else:
+        raise TypeError(
+             "Unserializable object {} of type {}".format(obj, type(obj))
+        )
     return obj