[release/1.7] Revert errdefs package

[dmcgowan]

Switching to the errdefs package in 1.7 is a breaking change since the new errdefs package was not stabilized. We can consider moving to the errdefs package once it is marked as 1.0 after the containerd 2.0 release.

As part of the changes in errdefs, we made sure that even if we don't have exact type compatibility, we can rely on interface compability. This will ensure that any version of the errdefs package or any similar errdefs package which uses the same interfaces will have error matches. Switching this in 1.7 was premature and unnecessary considering we can get compatibility with the interface checks. This has now been reverted and the error definitions synchronized with errdefs to ensure the interfaces are included.

This is currently causing some 1.7 builds to break after version resolution and is a blocker for 2.0 since it prevents us from moving up the errdefs package due to a circular dependency. This dependency could also be solved by bumping 1.7 to errdefs 0.2.0, but that is introducing another breaking change to 1.7 for a non-1.0 package.

[thaJeztah]

Ugh; this will be a painful one. Wasn't the errdefs package specifically MEANT so that errors between v2 and v1 could be handled? At least this will be a painful one with moby <--> buildkit <--> containerd

[dmcgowan]

Wasn't the errdefs package specifically MEANT so that errors between v2 and v1 could be handled? At least this will be a painful one with moby <--> buildkit <--> containerd

Yes, but errdefs 0.1.0 didn't solve that and can makes the situation more difficult since the package isn't 1.0 and not stable. Also buildkit and moby haven't adopted the errdefs package for their definitions and errdefs.Is functions will still work with this change. The interface approach is more reliable for now and what we already do for compatibility with Moby errors. This change still ensures errors will be handled between v1 and v2.

[thaJeztah]

Yeah, mostly concerned that code consumed from BuildKit will match different errors than Moby code if only one will update, and updating only the containerd dependency likely means that none of the cerrdefs.Is(...) will match anything

git describe --tags --match="v[0-9]*" HEAD
v0.16.0

git grep '"github.com/containerd/errdefs"' | wc -l
      97

git describe --tags --match="v[0-9]*" HEAD
v27.3.0
git grep '"github.com/containerd/errdefs"' | wc -l
     126
git grep 'cerrdefs.Is' | wc -l
      90

[dmcgowan]

BuildKit is doing its own thing with error handling and not directly handling errors from containerd yet, so that is not a concern yet. There is definitely still ongoing work in both BuildKit and Moby to get the error handling unified, but we shouldn't even try to rely on strict type matching until we have a 1.0 of errdefs, we should use interface matching via Is functions for now when needed.