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Philipp Dunkel
6a7f94c9bf
Mounting a virtual file system requires calling vfs.mount() from inside the program, so a program cannot itself be served from one: something already running has to mount the VFS first. Add two startup flags. --vfs-mount=<source> mounts a directory or an archive as a virtual file system, and may be repeated. --vfs-load=<source> mounts that source the same way and additionally runs the entry point and all subsequent require()/import resolution against it rather than against the real file system, so an application can be run straight out of a directory or a ZIP archive: node --experimental-vfs --vfs-load=my-app.zip Both options append to one list, so mounts happen in the order written: node --experimental-vfs --vfs-mount=a --vfs-load=b --vfs-mount=c mounts a, b and c in that order and runs b. Mounting the same source twice mounts it twice, at two mount points, and the entry point comes from the mount --vfs-load contributed rather than the earlier one. The provider backing a source is chosen from the source itself rather than from its name: a directory is served by RealFSProvider and a file whose bytes are a ZIP archive by ZipProvider, so an archive can carry any extension. vfs.registerProvider() registers a provider for formats there is no built-in for; selection is deferred until -r and --import preloads have run, so a preloaded module can register one before its source is claimed. The entry point comes from the mount the way `node <directory>` takes one, from package.json "main" or index.js. Nothing is consumed as an entry point argument, so every positional reaches the program unchanged from argv[2] on, and argv[1] reports the named source rather than the reserved mount point, which is an opaque implementation detail. --vfs-load may be given at most once, and is not permitted in NODE_OPTIONS: which entry point runs is the command line's decision, and NODE_OPTIONS is parsed first, so an environment variable could otherwise redirect any invocation. --vfs-mount is permitted there. Workers inherit the same mounts in the same order but not the loading: a worker mounts what the parent mounted and runs its own entry point. Signed-off-by: Philipp Dunkel <pip@pipobscure.com> PR-URL: https://github.com/nodejs/node/pull/65748 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com>