A way to `write_entry_stream` while retaining valid local file headers

[oeed]

I am trying to generate ZIPs in a fairly low memory environment for files that can be quite large, so reading the entire contents and using write_entry_whole unfortunately isn't feasible. I have been using write_entry_stream, which does work well, but I've found Java based consumers reject files with invalid local headers with errors such as:

java.io.IOException: java.util.zip.DataFormatException: invalid stored block lengths

The docs do mention this:

The generated Local File Header will be invalid, with no compressed size, uncompressed size, and a null CRC. This might cause problems with the destination reader.

But I was wondering if there was some potential way around it, or a way to write chunks of data rather than in whole entries? Thank you for this crate!

[Majored]

It sounds like the Java reader doesn't support files with data descriptors then, unfortunately.

Does the writer you're using implement Seek? One option I've been meaning to implement is double-writing, where you write a dummy local file header as you're going along, and then seek back and write the correct values in the LFH (and don't use a data description - acting as if it was written with write_entry_whole). Though obviously, this will require a bit of work so is not an immediate solution.