Python requests.exceptions.SSLError: EOF occurred in violation of protocol

Question

I would retrieve some information from an ABB G13 gateway that offer a RESTful JSON API. API is hosted by the gateway via https endpoint. Basic authentication mechanism is u

Answer 1

Step 1: Check that Python supports TLS 1.1

You may have a Python setup that only supports TLS 1.0 – not TLS 1.1 or above.

You can check it like this:

Python 3

from urllib.request import urlopen
urlopen('https://www.howsmyssl.com/a/check').read()

Python 2

from urllib2 import urlopen
urlopen('https://www.howsmyssl.com/a/check').read()

(If you get urllib.error.URLError: you may have to disable certificate verification. NOTE: doing this will disable SSL protections against evildoers who would impersonate or intercept traffic to that website - see https://en.wikipedia.org/wiki/Man-in-the-middle_attack )

import ssl
urlopen('https://www.howsmyssl.com/a/check', context=ssl._create_unverified_context()).read()

Check the output for the key tls_version. If it says TLS 1.0 and not TLS 1.1 or TLS 1.2 that could be the problem.

If you're using a virtualenv, be sure to run the command inside.

Step 2: Install Python with a newer version of OpenSSL

In order support TLS 1.1 or above, you may need to install a newer version of OpenSSL, and the install Python again afterwards. This should give you a Python that supports TLS 1.1.

The process depends on your operating system – here's a guide for OS X.

virtualenv users
For me, the Python outside of my virtualenv had TLS 1.2 support, so just I removed my old virtualenv, and created a new one with the same packages and then it worked. Easy peasy!