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web access - More complete "MutipartData" POSTs using URLFetch


I'm trying to upload a file to a wiki using Mathematica's URLFetch. Some preliminary work is required - one needs to log in to the wiki, obtain an edit token, and exchange some cookies with the wiki server. URLFetch can handle all of that. But then for the actual file upload, the MediaWiki API (e.g. http://www.mediawiki.org/wiki/API:Upload) specifies that one has to use the POST method with Content-Type=multipart/form-data, but the Mathematica implementation of multipart within URLFetch seems to be incomplete.


The Mathematica documentation of the option "MultipartData" of URLFetch says only:



to upload multipart data, each part must be of the form {name, mimeType, {bytes}}, where {bytes} is a list of bytes



This suggests that in the "Content-Disposition" header of each part of a multipart request, a name can be specified as in:



Content-Disposition: form-data; name="file"


but there seems to be no way to also specify a filename, as in



Content-Disposition: form-data; name="file"; filename="Apple.gif"

Finally, the MediaWiki API requires that a file name be specified; see e.g. the example of a multipart request at the very bottom of http://www.mediawiki.org/wiki/API:Upload (and when I try to upload a file without specifying a filename, the wiki server sends back an error message).


So my question: Is there a more complete implementation of the MultiPart protocol with URLFetch?




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