Requeue nodes when their tags change - #8
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nodesEqual compared name, online state and addresses, but not tags. Tags decide whether a node is managed at all via app.required_tags, so a node that gained or lost a relevant tag was never requeued unless one of its addresses happened to change at the same time. In practice that means tagging an existing device to bring it under dnsscale's management has no effect until the device's Tailscale address changes or the process restarts. Also switches the address comparison to slices.Equal, which is what the hand-rolled length check and loop were doing.
This was referenced Aug 8, 2026
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The bug
nodesEqualcompares name, online state and addresses, but not tags:https://github.com/jaxxstorm/dnsscale/blob/main/main.go#L440
Tags are what decide whether a node is managed at all, via
shouldManageNodeandapp.required_tags. Because a tag change doesn't makenodesEqualreturn false,syncNodesnever requeues the node, so:Restarting is currently the reliable way to pick up a tag change, which is a surprising thing to need.
What changed
nodesEqualnow compares tags as well, and the hand-rolled length-check-plus-loop over addresses becomesslices.Equal, which is what it was already doing.One thing I noticed but did not change
Onlineis compared here, but nothing downstream uses it —shouldManageNodeandreconcileboth ignore it, so the records produced for an online and an offline node are identical. SinceOnlineis derived astime.Since(LastSeen) < 5*time.Minute, every device crossing that threshold requeues a reconcile that rewrites byte-identical records, which costs a provider API call per address per transition.That's arguably wasted work, but removing
Onlinefrom the comparison would foreclose gating on it later, so I've left it alone. Happy to strip it in a follow-up if you'd rather.Tests
Adds
nodes_test.gocovering the comparison, including tag added / removed / replaced.go build ./...,go vet ./...andgo test ./...all pass.