feat(velocity): drain players via transfer before shutdown - #66
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A proxy pod that is rolled today kicks everyone on it. The preStop hook now calls a loopback drain endpoint instead: lobby players are moved to another proxy with a Minecraft transfer packet immediately, players inside a round stay until the round sends them back towards a lobby (that connect becomes the transfer), and at the deadline the rest is transferred regardless. New logins are denied while draining. Wait-only without GROUNDS_DRAIN_TRANSFER_HOST; endpoint is loopback so only the pod's own preStop hook can trigger it.
GROUNDS_DRAIN_TRANSFER_HOST becomes an override: without it the target is this region's own entry in the REGIONS catalogue (what /region already transfers players with), selected by REGION. One shared values file then drains correctly in every region.
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hbrombeer
marked this pull request as ready for review
August 1, 2026 19:46
This was referenced Aug 2, 2026
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Core of the proxy drain project: a Velocity pod that is rolled today kicks everyone on it. The chart's preStop hook (groundsgg/charts, grounds-velocity 0.9.0) now calls a loopback drain endpoint served by this plugin:
ServerPreConnectEvent).Endpoints (loopback only):
/drain/start?deadlineSeconds=N,/drain/players,/drain/status.GROUNDS_DRAIN_TRANSFER_HOSTunset = wait-only drain.Session correctness on transfer (reconnect vs. stale session) is handled by groundsgg/library-grpc-contracts#78 / groundsgg/service-player#95 / groundsgg/plugin-player#31 — deploy those first or transferred players bounce off
ALREADY_ONLINEfor up to 90s.Rollout order: contracts → service-player → plugin-player → this (new velocity image) → charts grounds-velocity 0.9.0 → deploy values (
drain.enabled,drain.transferHost,terminationGracePeriodSeconds).