Tableau 8 comes with an API that lets you create Tableau extracts from Java programs. I think its available for Python and at least one other language.
So until there is a Mongo driver, one option is to write a little program that creates an extract from your Mongo tables, and connect Tableau to the extract. Then regenerate the extract as frequently as needed.
We still can't write our own custom drivers, but this new API is certainly a step in the right direction.
Alteryx also has a product that can read Mongo and dump out a TDE if you don't feel like writing code.
Excellent - worthy of a dabble methinks. I know there is a neat schema analysis tool for Mongo on Github; in the final analysis, every document (aka row in SQL terms) can have unique structures within a collection (aka Table) there. However, almost every instance i've seen retains some form of structure with enough consistency that a programmers code can traverse the data simply. I think a quick hack of the Schema Analysis tool may give a general case that's good enough to for Tableau to touch any MongoDB instance, even if a scan of the whole database needs to be done as the connection opens.
I will go have a look at the API. Thank you.