Except when configuration makes curl be used. It did not seem worth
trying to tail the file when curl is downloading.
But when an interrupted download is resumed, it does not read the whole
existing file to hash it. Same reason discussed in
commit 7eb3742e4b76d1d7a487c2c53bf25cda4ee5df43; that could take a long
time with no progress being displayed. And also there's an open http
request, which needs to be consumed; taking a long time to hash the file
might cause it to time out.
Also in passing implemented it for git and external special remotes when
downloading from the web. Several others like S3 are within striking
distance now as well.
Sponsored-by: Dartmouth College's DANDI project
Added fileRetriever', which will let the remaining special remotes
eventually also support incremental verify.
Sponsored-by: Dartmouth College's DANDI project
Simply feed each chunk in turn to the incremental verifier.
When resuming an interrupted retrieve, it does not do incremental
verification. That would need to read the file, up to the resume point,
and feed it to the incremental verifier. That seems easy to get wrong.
Also it would mean extra work done before the transfer can start. Which
would complicate displaying progress, and would perhaps not appear to the
user as if it was resuming from where it left off. Instead, in that
situation, return UnVerified, and let the verification be done in a
separate pass.
Granted, Annex.CopyFile does manage all that, but it's not complicated
by dealing with chunks too.
Sponsored-by: Dartmouth College's DANDI project
I'm now reasonably sure I've identified both cases where this can
happen. v8 upgrades and certian filesystems eg NFS. Both are handled as
well as can be, though it may involve some extra checksumming work.