We are creating an XML API for Joomla that enables partner sites to produce new makes up about their customers on our website.

We have produced a stand alone PHP script that processes and validates the API request, however we have to really produce the new accounts. I was initially considering just carrying out a CURL call to submit the register form, but we recognized that there's an problem using the user token. Can there be another clean way to produce a user account without starting the very center of Joomla? As we do need to perform some surgery, what's the easiest method to approach it?

You need to use Joomla internal classes, like JUser, since there lots of internal logic for example password salting. Produce a custom script that utilizes the values in the API request and saves the customers within the database using techniques from Joomla User Classes.

Two methods to add joomla customers making use of your custom code is an excellent tutorial. The approach works. I have used this method in certain projects.

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