javascript download multiple files as zip

For this reason, the gains in speed from extracting large uncompressed tar files far outweigh any slight gain in size reduction from compressing already compressed files. When working with big data in bioinformatics for example, any (text-based) files that can be significantly reduced in size by compression (eg gzip) are typically already compressed and travel around as compressed files. © The Apache Software Foundation from Jackrabbit Oak docs

The real challenge, however, is implementing everything after the archive has been created, for example: How long are the users going to wait and how are you going to notify them when the download is ready? How long will you keep the file available for download? What if files change after archives are created but before they’re completely downloaded? It is only after all of these considerations that the streaming alternative becomes the clear winner.

The question then becomes: archive first and download after or archive on the fly with a streaming download? Archiving to a temp file and then serving the static file from disk is appealing because it’s familiar and simple to implement. The best workaround we have is to archive (eg tar or zip) the files into a single file for download and this is still what’s used by Google Drive, MS SharePoint, and all the big names. Providing lists of file URLs to browser extensions and download manager software is always an option but it’s a hard sell and especially inconvenient for one-off visitors that don’t want to install new software just to download a single set of data.

HTTP/3 promises more flexibility with multiplexing and multi-file downloads because it instead sits on top of the QUIC protocol but it will still be some time before there is widespread adoption and new standards for browser file downloads. The limitation is more specifically due to the underlying TCP that treats all transfers as single files or streams causing head-of-line blocking. The ability to download multiple files from a single browser click has long been missing from HTTP but it is a requisite feature for most web-based file services.

A core requirement was a pick-list feature so users could create sets of files to be downloaded all at once from a browser. One of my first challenges for Weill Cornell Medicine was to develop a file distribution portal that allowed genomic sequencing labs to distribute big data files to collaborators over the web.

Javascript download multiple files as zip