If the JSON connection config file contains C/C++-style comments, or a list of SASL mechanisms, then the client errors.
The JSON specification does not allow for comments. However, the connection config file specifies that c/c++ comments may be embedded within the JSON. A comment eliminator needs to be used before the JSON is loaded.
The call to pn_sasl_allowed_mechs() requires a const char* space-separated list of SASL mechs. The python does not correctly handle this case, as it is passing the mechs as a Python list of strings. A single string containing a mech instead of a list in the JSON should also be handled.