I want to do something fairly simple: read files from one ZIP and add them to another, so I can remove and replace files. This led me to a couple things that seem to be missing from the API.
The simple approach would be to open each file in the source ZIP, and hand it off to newzip.write(). There's a missing piece, though: there's no API that lets me pass in a file-like object and a ZipInfo, to preserve metadata. zip.write() only takes the filename and compression method, not a ZipInfo; writestr takes a ZipInfo but only accepts a string, not a file. Is there an API call I'm missing? (This seems like the fundamental API for adding files, that write and writestr should be calling.) The correct approach is to copy the data directly, so it's not recompressed. This would need two new API calls: rawopen(), acting like open() but returning a direct file slice and not decompressing data; and rawwrite(zinfo, file), to pass in pre-compressed data, where the compression method in zinfo matches the compression type used. I was surprised that I couldn't find the former. The latter is an advanced one, important for implementing any tool that modifies large ZIPs. Short-term, at least, I'll probably implement these externally. -- Glenn Maynard -- http://mail.python.org/mailman/listinfo/python-list
