When changeing Graphite’s visualization to Grafana, I met the following exception

TypeError: Cannot read property 'length' of undefined
    at convertDataPointsToMs (http://hostname:80/public/app/boot.74ebeed4.js:15:17351)
    ...

I inspected the request in Chrome, searched the exception and found some pages such as sometimes format=json requests return png’s, which is outdated. The problem described has been fixed in my Graphite version 0.9.10.

I added more log in graphite-web code and compared Grafana’s request with graphite-web’s, founding that they are using different http method when calling /render:

• graphite-web: get
• Grafana: post

Searched again and founded Why are you POSTing to graphite /render?, which said that upgrading to Graphite 0.9.13 would fix this.

The code raises/solves exception is

# graphite-web/webapp/graphite/render/views.py
def parseOptions(request):
-  queryParams = request.GET
+  queryParams = request.GET.copy()
+  queryParams.update(request.POST)