pickfirstleaf: Fix shuffling of addresses in resolver updates without endpoints #8610
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arjan-bal
added
Type: Bug
Area: Resolvers/Balancers
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #8610 +/- ##
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+ Coverage 82.11% 82.16% +0.04%
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Files 415 415
Lines 40692 40697 +5
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+ Hits 33416 33439 +23
+ Misses 5887 5881 -6
+ Partials 1389 1377 -12
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easwars
approved these changes
Sep 25, 2025
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| pfBuilder := balancer.Get(pfbalancer.Name) | ||
| shffleConfig, err := pfBuilder.(balancer.ConfigParser).ParseConfig(json.RawMessage(`{ "shuffleAddressList": true }`)) |
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Lol, here and in the next statement, prefer adding the u back into shuffle. Saving one character in the variable name is not going to be very useful :)
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Changed to using complete words.
| if err != nil { | ||
| t.Fatal(err) | ||
| } | ||
| activeCfg := noShffleConfig |
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Nit: remove this line since this assignment is anyways happening on line 521.
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Changed to only declaring the variable, but not initializing here.
arjan-bal
added a commit
to arjan-bal/grpc-go
that referenced
this pull request
Oct 1, 2025
… endpoints (grpc#8610) The new `pick_first`, which is the default, doesn't shuffle the addresses at all for resolver updates that are missing the `Endpoints` field. This change fixes that. Since [gRPC automatically sets the the missing `Endpoints`](https://github.com/grpc/grpc-go/blob/1059e84f885bf7ed65b3b1a4fbe914360d8ab5b1/resolver_wrapper.go#L136-L138), occurrence of this bug should be uncommon in practice. RELEASE NOTES: * balancer/pick_first: When configured, shuffle addresses in resolver updates that lack endpoints. Since gRPC automatically adds endpoints to resolver updates, this bug should only affect implementers of custom LB policies that use pick_first for delegation but don't forward the endpoints.
arjan-bal
added a commit
that referenced
this pull request
Oct 3, 2025
Original PRs: #8610, #8615 RELEASE NOTES: * balancer/pick_first: * Fix bug that can cause balancer to get stuck in `IDLE` state on backend address change. * When configured, shuffle addresses in resolver updates that lack endpoints. Since gRPC automatically adds endpoints to resolver updates, this bug should only affect implementers of custom LB policies that use pick_first for delegation but don't forward the endpoints.
Pranjali-2501
pushed a commit
to Pranjali-2501/grpc-go
that referenced
this pull request
Oct 6, 2025
… endpoints (grpc#8610) The new `pick_first`, which is the default, doesn't shuffle the addresses at all for resolver updates that are missing the `Endpoints` field. This change fixes that. Since [gRPC automatically sets the the missing `Endpoints`](https://github.com/grpc/grpc-go/blob/1059e84f885bf7ed65b3b1a4fbe914360d8ab5b1/resolver_wrapper.go#L136-L138), occurrence of this bug should be uncommon in practice. RELEASE NOTES: * balancer/pick_first: When configured, shuffle addresses in resolver updates that lack endpoints. Since gRPC automatically adds endpoints to resolver updates, this bug should only affect implementers of custom LB policies that use pick_first for delegation but don't forward the endpoints.
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The new
pick_first, which is the default, doesn't shuffle the addresses at all for resolver updates that are missing theEndpointsfield. This change fixes that. Since gRPC automatically sets the the missingEndpoints, occurrence of this bug should be uncommon in practice.RELEASE NOTES: