fork of https://github.com/sourcegraph/zoekt
rpc: use old module name when registering gob values (#408)
When rolling out the module rename everything worked unless your zoekt
cluster was out of sync with the sourcegraph cluster. Then in that case
we couldn't match up names in gob decoding, leading to the RPC wire
protocol breaking. The error showing up one sourcegraph.com was like:
error during decoding: ...
Test Plan: printed the names it generates and inspected it. Additionally
I will do more testing with sourcegraph and mismatched versions to
ensure everything continues to work.
author
Keegan Carruthers-Smith
committer
GitHub
date
(Aug 16, 2022, 3:03 PM +0100)
commit
c9182fcd
c9182fcd2a2eac3bd0546e78efabb6ba224c852b
parent
5ee92f5a
5ee92f5abab3047f8b36172f31e49a4922dedc27
+77
-18
+77
-18
rpc/rpc.go
+77
-18
rpc/rpc.go
···
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"encoding/gob"
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"fmt"
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"net/http"
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"reflect"
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"strings"
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"sync"
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"time"
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"github.com/keegancsmith/rpc"
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"github.com/sourcegraph/zoekt"
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"github.com/sourcegraph/zoekt/query"
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"github.com/sourcegraph/zoekt/rpc/internal/srv"
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"github.com/keegancsmith/rpc"
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)
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// DefaultRPCPath is the rpc path used by zoekt-webserver
···
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// once, because calls to gob.Register are protected by a sync.Once.
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func RegisterGob() {
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once.Do(func() {
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gob.Register(&query.And{})
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gob.Register(&query.BranchRepos{})
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gob.Register(&query.BranchesRepos{})
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gob.Register(&query.Branch{})
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gob.Register(&query.Const{})
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gob.Register(&query.GobCache{})
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gob.Register(&query.Language{})
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gob.Register(&query.Not{})
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gob.Register(&query.Or{})
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gob.Register(&query.Regexp{})
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gob.Register(&query.RepoRegexp{})
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gob.Register(&query.RepoSet{})
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gob.Register(&query.Repo{})
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gob.Register(&query.Substring{})
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gob.Register(&query.Symbol{})
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gob.Register(&query.Type{})
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gob.Register(query.RawConfig(41))
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gobRegister(&query.And{})
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gobRegister(&query.BranchRepos{})
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gobRegister(&query.BranchesRepos{})
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gobRegister(&query.Branch{})
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gobRegister(&query.Const{})
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gobRegister(&query.GobCache{})
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gobRegister(&query.Language{})
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gobRegister(&query.Not{})
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gobRegister(&query.Or{})
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gobRegister(&query.Regexp{})
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gobRegister(&query.RepoRegexp{})
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gobRegister(&query.RepoSet{})
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gobRegister(&query.Repo{})
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gobRegister(&query.Substring{})
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gobRegister(&query.Symbol{})
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gobRegister(&query.Type{})
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gobRegister(query.RawConfig(41))
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})
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}
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// gobRegister exists to keep backwards compatibility around renames of the go
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// module. This is to avoid breaking the wire protocol due to refactors. In
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// particular in August 2022 we renamed the go module from
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// github.com/google/zoekt to github.com/sourcegraph/zoekt which breaks the
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// wire protocol. So this function will replace those names so we keep using
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// google/zoekt.
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func gobRegister(value any) {
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name := gobRegister_name(value)
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name = strings.Replace(name, "github.com/sourcegraph/", "github.com/google/", 1)
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gob.RegisterName(name, value)
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}
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// gobRegister_name is copy-pasta from the stdlib gob.Register, returning the
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// name it picks for gob.RegisterName.
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func gobRegister_name(value any) string {
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// Default to printed representation for unnamed types
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rt := reflect.TypeOf(value)
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name := rt.String()
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// But for named types (or pointers to them), qualify with import path (but see inner comment).
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// Dereference one pointer looking for a named type.
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star := ""
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if rt.Name() == "" {
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if pt := rt; pt.Kind() == reflect.Pointer {
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star = "*"
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// NOTE: The following line should be rt = pt.Elem() to implement
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// what the comment above claims, but fixing it would break compatibility
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// with existing gobs.
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//
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// Given package p imported as "full/p" with these definitions:
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// package p
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// type T1 struct { ... }
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// this table shows the intended and actual strings used by gob to
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// name the types:
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//
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// Type Correct string Actual string
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//
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// T1 full/p.T1 full/p.T1
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// *T1 *full/p.T1 *p.T1
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//
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// The missing full path cannot be fixed without breaking existing gob decoders.
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rt = pt
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}
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}
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if rt.Name() != "" {
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if rt.PkgPath() == "" {
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name = star + rt.Name()
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} else {
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name = star + rt.PkgPath() + "." + rt.Name()
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}
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}
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return name
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}