Regarding certificates, you should be able to pass them using the http_arguments variable.
As for converting JSON response objects to arrays, there is the ConvertObjects parameter. It only converts the top level object. Just let me know if that is enough for your purposes.
In any case always take at the documentation to see if what you need is already implemented. Otherwise post a new topic here.
phpclasses.org/package/7700-PHP-Aut
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