It seems to be possible for anyone to get a list from all edx courses. unfortunately the available documents are looking incomplete.
Is there any way to obtain a course list?
Are you talking about the list of courses running on edx.org? For that, you would need an OAuth key to access that API endpoint, and I don't believe that edx.org currently gives out OAuth keys. That API endpoint is currently intended for internal use only.
If you want to run your own Open edX installation, then you'll be able to access this API endpoint from your own instance, and it will return information about the courses you have running on your own installation.
But you do have an other option, you can use RSS feed from www.edx.org
https://www.edx.org/api/v2/report/course-feed/rss
i found this here
i hope this helps !