atomicallyWriteTo: remove temporary file prior to creating it #19243
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| */ | ||
| @CanIgnoreReturnValue | ||
| protected byte[] atomicallyWriteTo(Path outputPath, String uniqueSuffix) throws IOException { | ||
| Path tmpPath = outputPath.getFileSystem().getPath(outputPath.getPathString() + uniqueSuffix); |
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The fact that you're seeing this problem (and we've seen some similar ones) just goes to show that the uniqueSuffix is insufficiently unique. We should rather add something truly unique here and have the uniqueSuffix just serve to indicate what it's used for (which is most of the usage I see today).
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Actually using a deterministic suffix here is actually not that bad. It means that if the process is repeated, any stale temporary files get cleaned up automatically, right?
This change is the same in spirit to bazelbuild#19241. When using Bazel in combination with bb_clientd, bb_clientd may restore a copy of bazel-out/ from a snapshot. Files restored from the snapshot are not mutable, as they may be backed by other snapshots, a remote CAS, etc. etc. etc.. This change extends atomicallyWriteTo() to always write contents into a new file that is guaranteed to be writable. The logic that's added here is merely copy-pasted from what's already present at the bottom of the same function.
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@coeuvre @larsrc-google PTAL! |
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This change is the same in spirit to #19241. When using Bazel in combination with bb_clientd, bb_clientd may restore a copy of bazel-out/ from a snapshot. Files restored from the snapshot are not mutable, as they may be backed by other snapshots, a remote CAS, etc. etc. etc..
This change extends atomicallyWriteTo() to always write contents into a new file that is guaranteed to be writable. The logic that's added here is merely copy-pasted from what's already present at the bottom of the same function.