feat(shard-distributor): add SpectatorPeerChooser for shard-aware routing #7478
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jakobht
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service/sharddistributor/client/spectatorclient/peer_chooser.go
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service/sharddistributor/client/spectatorclient/peer_chooser.go
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| } | ||
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| // Extract GRPC address from owner metadata | ||
| grpcAddress, ok := owner.Metadata[grpcAddressMetadataKey] |
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nit: a bit unexpected to see such specifics as grpcAddressMetadataKey here.
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Yeah, I would like better separation. We need to address here, so I decided to do it like this, but it does feel like mixing application and network level.
service/sharddistributor/client/spectatorclient/peer_chooser.go
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Implement a YARPC peer chooser that routes requests to the correct
executor based on shard ownership. This is the shard distributor
equivalent of Cadence's RingpopPeerChooser.
Flow:
1. Client calls RPC with yarpc.WithShardKey("shard-key")
2. Chooser queries Spectator for shard owner
3. Extracts grpc_address from owner metadata
4. Creates/reuses peer for that address
5. Returns peer to YARPC for connection
The peer chooser maintains a cache of peers and handles concurrent
access safely. It uses the x-shard-distributor-namespace header to
determine which namespace's spectator to query.
Dependencies:
- Requires spectator GetShardOwner to return metadata (see previous commit)
Signed-off-by: Jakob Haahr Taankvist <[email protected]>
Signed-off-by: Jakob Haahr Taankvist <[email protected]>
The tests have dependency issues with mock generation that need to be resolved separately. The peer chooser implementation is complete and functional. Signed-off-by: Jakob Haahr Taankvist <[email protected]>
Tests cover: - Success path with peer creation - Peer reuse on subsequent calls - Error cases (missing shard key, namespace header, spectator not found) - Lifecycle methods (Start, Stop, IsRunning) - SetSpectators method Signed-off-by: Jakob Haahr Taankvist <[email protected]>
Signed-off-by: Jakob Haahr Taankvist <[email protected]>
Signed-off-by: Jakob Haahr Taankvist <[email protected]>
…peer creation and mutex lock and unlock Signed-off-by: Jakob Haahr Taankvist <[email protected]>
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This PR depends on #7476 (spectator return metadata) being merged first.
What changed?
Added
SpectatorPeerChooserthat implements YARPC's peer.Chooser interface to route requests to the correct executor based on shard ownership.Why?
Enable executor-to-executor communication in the shard distributor canary system. The peer chooser queries the Spectator to find which executor owns a shard, then routes requests to that executor's gRPC address.
How did you test it?
Unit tests
Potential risks
None
Release notes
Documentation Changes