jschoubben
8431ecfb48
novox/hq 04-ISSUES/107. A declaration's only identity was the digest of its bytes: a host could say "not the last" and could not say "older". On the link, nothing refused an older one at all, and the drain picked the last to arrive — wrong exactly when it mattered, a backlog drained out of order or a broker that split a burst. A declaration may now carry a sequence, one higher per send. A host refuses one lower than what it kept, whole, and says why. The drain keeps the highest sequence in a batch rather than the last to arrive. Only when both sides claim an order. Absent reads as zero — "no ordering claimed", not "first" — so a controller that sends none is still understood and a host that kept one before it understood them compares nothing. That is what lets hosts go first and the controller follow, which is the order 087 says a new field needs.
51 lines
1.6 KiB
Go
51 lines
1.6 KiB
Go
package link
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import (
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"encoding/json"
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"testing"
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"time"
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)
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// The drain picked the last to arrive. A backlog longer than the batch, or a broker that split a
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// burst, delivered a superseded declaration last (novox/hq 04-ISSUES/107).
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func sequenced(t *testing.T, n int64) *said {
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t.Helper()
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inner, err := json.Marshal(map[string]any{"declaration": 1, "resources": []any{}, "sequence": n})
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if err != nil {
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t.Fatal(err)
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}
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body, err := json.Marshal(Signed{Declaration: inner, Signature: []byte("s")})
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if err != nil {
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t.Fatal(err)
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}
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return &said{body: body}
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}
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func TestTheDrainKeepsTheHighestSequenceNotTheLastToArrive(t *testing.T) {
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waiting := make(chan Declaration, 8)
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waiting <- sequenced(t, 9)
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waiting <- sequenced(t, 4) // arrived last, composed earlier
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latest, aside := newest(waiting, sequenced(t, 8), 30*time.Millisecond)
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if got := sequenceOf(latest.Body()); got != 9 {
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t.Fatalf("the drain kept sequence %d, and 9 was waiting", got)
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}
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if len(aside) != 2 {
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t.Fatalf("%d set aside, wanted 2 (the 8 and the late 4)", len(aside))
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}
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}
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func TestWithoutSequencesTheLastToArriveStillWins(t *testing.T) {
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// The behaviour this had before, kept for a controller that sends no order.
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apply, aside := newest(arriving("two", "three"), &said{body: []byte("one")}, 30*time.Millisecond)
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if string(apply.Body()) != "three" || len(aside) != 2 {
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t.Fatalf("applied %q with %d set aside", apply.Body(), len(aside))
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}
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}
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func TestAnUnreadableBodyClaimsNoOrder(t *testing.T) {
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if got := sequenceOf([]byte("not json")); got != 0 {
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t.Fatalf("garbage claimed sequence %d", got)
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}
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}
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