Backend validation tool (go) POST request failures

[soxofaan]

While running the go backend validation tool (Open-EO/openeo-backend-validator) against localhost openeo-python-driver, I found that non of the POST request were working. The posted data seems empty, resulting in json decode issues

400 Bad Request: Failed to decode JSON object: Expecting value: line 1 column 1 (char 0)

The post data is being send, because it works against other backends

[soxofaan]

Lost half a day on this rabbit hole

Apparently it is because the go HTTP client sends the POST data with chunked encoding, which is not well supported by our setup of werkzeug/flask/gunicorn out of the box

some references:

• request.get_data() is always empty because of flask/werkzeug bug with chunked transfer encoding openfaas/python-flask-template#5
• Request Body Size Limit? benoitc/gunicorn#1733
• Support wsgi.input_terminated flag benoitc/gunicorn#1653
• https://medium.com/@DJetelina/python-and-chunked-transfer-encoding-11325245a532

[soxofaan]

one solution is to upgrade to gunicorn>=20.0.1, however the dependency was explicitly pinned down by Open-EO/openeo-geopyspark-driver@2b5be85 so I have to check if that is possible