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Git archive checksums may change

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Re: Git archive checksums may change

#21
post #5

GitHub will need to revert this change. They've just crippled pretty much every "from source" package manager out there.

Per the post, this was a change to git itself: https://github.com/git/git/commit/4f4be00d302bc52d0d9d5a3d47...

They could just produce tar output and compress that using system gzip. The “git archive” tool supports many output formats.

Re: Git archive checksums may change

#22

Earlier quoted context omitted.

Using SHA hashes when building guarantees that the code that you are building is what you think it is. How else would you verify dependencies like this, GPG signatures would have the same issue if you change the underlying bits.

a git checkout of the code at that particular tag hasn't changed. Just the tarball that git archive generates has.

The two main problems are:

A) How do you catch tarballs that have extra files injected that aren't part of your manifest

B) What does the performance of this look like? Certainly for traditional HDDs this is going to kill performance, but even for SSDs I think verifying a bunch of small files is going to be less efficient than verifying the tarball.

Re: Git archive checksums may change

#23

Hyrum's Law strikes again. It kind of doesn't matter what you document. If you weren't randomizing your checksum previously [1], you can't just spring this on the community and blame it for the fallout. I'm more shocked that there's resistance from the GitHub team saying "but we documented this isn't stable". Default stance for the team should be rollback & reevaluate an alternate path forward when the scope is this…

It's Microsoft. Just as the Apple of today is not the Apple of ten years ago, the GitHub today is not the GitHub of ten years ago. It's literally different people.

The people who made the things you love have mostly moved on, and the brand is being run by different people with different values now.

There's a little bit of an argument that such things are a bait-and-switch, but such is the nature of a large and multigenerational corporation.

Re: Git archive checksums may change

#25
post #15
post #5

GitHub will need to revert this change. They've just crippled pretty much every "from source" package manager out there.

If those tools incorrectly assume an API contract which doesn't exist, isn't the right answer to fix those tools?

In theory, sure, that's what we'd do in an ideal world.

In the real world it will take millions of dollars of eng labor just to update the hashes to fix everything that's currently broken and millions more to actually implement something better and move everyone over to it.

This isn't worth it, GitHub needs to just revert the change and then engineer a way to keep hashes stable going forward.

Re: Git archive checksums may change

#26

Hey folks. I'm the product manager for Git at GitHub. We're sorry for the breakage, we're reverting the change, and we'll communicate better about such changes in the future (including timelines). Also posted here: https://github.com/bazel-contrib/SIG-rules-authors/issues/11...

[deleted]

Re: Git archive checksums may change

#27

Hey folks. I'm the product manager for Git at GitHub. We're sorry for the breakage, we're reverting the change, and we'll communicate better about such changes in the future (including timelines). Also posted here: https://github.com/bazel-contrib/SIG-rules-authors/issues/11...

We updated our Git version which made this change for the reasons explained. At the time we didn't foresee the impact. We're quickly rolling back the change now, as it's clear we need to look at this more closely to see if we can make the changes in a less disruptive way. Thanks for letting us know.

Re: Git archive checksums may change

#28

Im thinking of all the bazel build rules that are about to break from my last company. Someone will have a fun day updating hundreds of hashes.

Do they let Github generate the archives as one of the build rules instead of performing the archival and compression locally and uploading the result?

Re: Git archive checksums may change

#29

Ah, this will presumably break some Arch Linux AUR packages. Preparing for bug reports.

Yep, it has already broken labwc for me.

    ==> Validating source files with b2sums...
        labwc-0.6.1.tar.gz ... FAILED
    ==> ERROR: One or more files did not pass the validity check!

Re: Git archive checksums may change

#30
post #18

Im thinking of all the bazel build rules that are about to break from my last company. Someone will have a fun day updating hundreds of hashes.

If they're using multiple URLs like a good Bazel user then they shouldn't be impacted.

They did where applicable but i know that not all of them had multiple
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