[SOLVED] Use ngrok url as callback url for facebook webhook, but is recognized "not whitelisted"

Use ngrok url as callback url for facebook webhook, but is recognized "not whitelisted"

My IDE is Pycharm. I want to test my app locally, so I run my service locally and use ngrok to expose my app to Internet.

The url showed by ngrok is https://436cb7e9.ngrok.io

But when I want to verify the facebook webhook callback url use this url above, it shows

ERROR 2017-12-27 08:16:37,407 wsgi_server.py:329] Request Host 436cb7e9.ngrok.io not whitelisted. Enabled hosts are set(['localhost'])

I ran the app well before, but I don't know why this time it shows an error. Could somebody gives me suggestion?

Solution

After a bit of digging and thanks to Brady's comment about the gcloud version, I found out that all you need to fix this is to add a flag when you run your app.

So, say you run your app locally with:

python $APPENGINE/dev_appserver.py

just change it to:

python $APPENGINE/dev_appserver.py --enable_host_checking=false

and you should not have the host whitelist errors anymore.

For more information, checkout the release notes here: https://cloud.google.com/appengine/docs/standard/python/release-notes#december_5_2017

This seems to be working fine for me on gcloud 183.0.0 and 187.0.0 (the latest version at the time of writing of this comment).