This code is only an LTI 1.1 test and won't be updated to LTI 1.3. LTI 1.3 is far more complex then LTI 1.1 and my recommendation for building LTI 1.3 tools is to use the Tsugi framework (www.tsugi.org) and the Tsugi LMSTest tool to exercise your LTI 1.3 implementation.

You can use this test to exerciese your LTI 1.1 tools and LMS's at:

https://www.tsugi.org/lti-test/