ingest/ledgerbackend: Let filewatcher check for binary hash to detect captive core updates. #4050
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| "github.com/stellar/go/support/log" | ||
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| type hash []byte |
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nit: I don't think this type alias provides much benefit since we end up using bytes.Equal to compare hashes anyways
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Fair point. I slightly prefer to keep the type definition though, so I defined a Equals method for type hash that just calls byte.Equals.
ingest/ledgerbackend/file_watcher.go
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| "github.com/stellar/go/support/log" | ||
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| type hash []byte | ||
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| func (h *hash) Equals(other hash) bool { |
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what's the rationale for making the function have a pointer receiver?
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I wasn't thinking too much about it. I think defining it on the object itself makes a copy of it, which doesn't seem like a big deal either way. Do you have a reason to prefer one or the other?
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In https://github.com/golang/go/wiki/CodeReviewComments#receiver-type it states:
If the receiver is a slice and the method doesn't reslice or reallocate the slice, don't use a pointer to it.
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Sounds good to me. Updated.
PR Checklist
PR Structure
otherwise).
services/friendbot, orallordocif the changes are broad or impact manypackages.
Thoroughness
.mdfiles, etc... affected by this change). Take a look in the
docsfolder for a given service,like this one.
Release planning
needed with deprecations, added features, breaking changes, and DB schema changes.
semver, or if it's mainly a patch change. The PR is targeted at the next
release branch if it's not a patch change.
What
Let
file_watchercheck for binary hash to detect captive core updates.Why
Horizon watches it's captive stellar-core binary timestamp to detect if a new version has been deployed. However, the binaries are timestamped with the package changelog, which is not dynamically updated during build.
Known limitations
The hash function currently takes < ~30ms to finish. The 10 second duration for
file_watcher's loop should be sufficient.