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package providerhealth
import (
"context"
"fmt"
"log/slog"
"os"
"sync"
"testing"
"time"
"github.com/redis/go-redis/v9"
)
type captureSink struct {
events []Event
}
func (s *captureSink) Enqueue(event Event) { s.events = append(s.events, event) }
func TestTrackerOpensAndRecoversCircuit(t *testing.T) {
now := time.Date(2026, time.August, 6, 0, 0, 0, 0, time.UTC)
tracker := New(Options{FailureThreshold: 3, OpenDuration: 30 * time.Second, Now: func() time.Time { return now }})
key := RouteKey{ModelID: "openai/test", ProviderID: "primary", WireAPI: "responses"}
for _, status := range []int{503, 429, 504} {
tracker.Observe(key, Observation{StatusCode: status, Latency: 100 * time.Millisecond, Failed: true})
}
if !tracker.CircuitOpen(key) {
t.Fatal("circuit did not open after consecutive retryable failures")
}
snapshot := tracker.Snapshot()
if len(snapshot) != 1 || snapshot[0].State != "open" || snapshot[0].AvailabilityPercent != 0 || snapshot[0].CircuitOpenUntil == nil {
t.Fatalf("unexpected open snapshot: %+v", snapshot)
}
now = now.Add(31 * time.Second)
if tracker.CircuitOpen(key) {
t.Fatal("circuit did not permit a recovery attempt after cooldown")
}
tracker.Observe(key, Observation{StatusCode: 200, Latency: 50 * time.Millisecond})
snapshot = tracker.Snapshot()
if snapshot[0].State != "healthy" || snapshot[0].ConsecutiveFailures != 0 || snapshot[0].LastHealthyAt == nil || snapshot[0].HeaderLatencyEWMA < 50 {
t.Fatalf("unexpected recovered snapshot: %+v", snapshot[0])
}
}
func TestTrackerRecordsActiveProbeMetadata(t *testing.T) {
now := time.Date(2026, time.August, 6, 1, 0, 0, 0, time.UTC)
tracker := New(Options{Now: func() time.Time { return now }})
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "embeddings"}
tracker.Observe(key, Observation{StatusCode: 200, Latency: 20 * time.Millisecond, Active: true})
status := tracker.Snapshot()[0]
if status.ActiveProbes != 1 || status.LastProbeAt == nil || !status.LastProbeAt.Equal(now) || status.State != "healthy" {
t.Fatalf("unexpected active probe status: %+v", status)
}
}
func TestTrackerRecordsTTFTWithoutDoubleCountingAvailability(t *testing.T) {
tracker := New(Options{})
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "responses"}
tracker.Observe(key, Observation{StatusCode: 200, Latency: 20 * time.Millisecond})
tracker.ObserveTTFT(key, 100*time.Millisecond)
tracker.ObserveTTFT(key, 200*time.Millisecond)
status, found := tracker.StatusFor(key)
if !found || status.Attempts != 1 || status.RecentSamples != 1 || status.TTFTSamples != 2 || status.TTFTEWMA != 120 {
t.Fatalf("unexpected TTFT status: %+v", status)
}
}
func TestTrackerSharesLocalEventsWithoutRepublishingImportedEvents(t *testing.T) {
sink := &captureSink{}
tracker := New(Options{Sink: sink})
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "responses"}
tracker.Observe(key, Observation{StatusCode: 200, Latency: 20 * time.Millisecond})
tracker.ObserveTTFT(key, 100*time.Millisecond)
if len(sink.events) != 2 || sink.events[0].Kind != EventOutcome || sink.events[1].Kind != EventTTFT {
t.Fatalf("unexpected published events %+v", sink.events)
}
tracker.ApplyShared(Event{Kind: EventOutcome, Key: key, StatusCode: 503, Failed: true, ObservedAt: time.Now()})
tracker.ApplyShared(Event{Kind: EventTTFT, Key: key, LatencyMillis: 250, ObservedAt: time.Now()})
if len(sink.events) != 2 {
t.Fatalf("imported observations were republished: %d events", len(sink.events))
}
status, found := tracker.StatusFor(key)
if !found || status.Attempts != 2 || status.SharedAttempts != 1 || status.TTFTSamples != 2 || status.SharedTTFTSamples != 1 {
t.Fatalf("unexpected shared status %+v", status)
}
}
func TestSharedFailuresOpenLocalCircuit(t *testing.T) {
now := time.Date(2026, time.August, 6, 2, 0, 0, 0, time.UTC)
tracker := New(Options{FailureThreshold: 3, OpenDuration: 30 * time.Second, Now: func() time.Time { return now }})
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "responses"}
for range 3 {
tracker.ApplyShared(Event{Kind: EventOutcome, Key: key, StatusCode: 503, Failed: true, ObservedAt: now})
}
status, found := tracker.StatusFor(key)
if !found || !tracker.CircuitOpen(key) || status.State != "open" || status.Attempts != 3 || status.SharedAttempts != 3 {
t.Fatalf("shared failures did not open the circuit: %+v", status)
}
}
func TestRedisHistoryDropsWithoutBlockingWhenQueueIsFull(t *testing.T) {
client := redis.NewClient(&redis.Options{Addr: "127.0.0.1:1"})
defer client.Close()
history := NewRedisHistory(HistoryOptions{Enabled: true, Client: client, QueueSize: 1,
Logger: slog.New(slog.NewTextHandler(ioDiscard{}, nil))})
event := Event{Kind: EventOutcome, Key: RouteKey{ModelID: "model", ProviderID: "provider"}, ObservedAt: time.Now()}
history.Enqueue(event)
history.Enqueue(event)
if history.Dropped() != 1 {
t.Fatalf("dropped = %d, want 1", history.Dropped())
}
}
func TestRedisHistorySharesAndReplaysObservations(t *testing.T) {
redisURL := os.Getenv("AIGW_TEST_REDIS_URL")
if redisURL == "" {
t.Skip("AIGW_TEST_REDIS_URL is not set")
}
stream := fmt.Sprintf("aigw:test:provider-health:%d", time.Now().UnixNano())
options, err := redis.ParseURL(redisURL)
if err != nil {
t.Fatal(err)
}
cleanupClient := redis.NewClient(options)
t.Cleanup(func() {
_, _ = cleanupClient.Del(context.Background(), stream).Result()
_ = cleanupClient.Close()
})
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "responses"}
first := New(Options{})
second := New(Options{})
firstHistory := NewRedisHistory(HistoryOptions{Enabled: true, RedisURL: redisURL, Stream: stream, Instance: "first",
TTL: time.Minute, MaxEvents: 100, Logger: slog.New(slog.NewTextHandler(ioDiscard{}, nil))})
secondHistory := NewRedisHistory(HistoryOptions{Enabled: true, RedisURL: redisURL, Stream: stream, Instance: "second",
TTL: time.Minute, MaxEvents: 100, Logger: slog.New(slog.NewTextHandler(ioDiscard{}, nil))})
if firstHistory == nil || secondHistory == nil {
t.Fatal("Redis histories were not configured")
}
t.Cleanup(func() { _ = firstHistory.Close() })
t.Cleanup(func() { _ = secondHistory.Close() })
first.SetSink(firstHistory)
go firstHistory.Run(ctx, first)
go secondHistory.Run(ctx, second)
first.Observe(key, Observation{StatusCode: 200, Latency: 10 * time.Millisecond})
first.ObserveTTFT(key, 40*time.Millisecond)
waitForSharedStatus(t, second, key, 1, 1)
status, _ := first.StatusFor(key)
if status.SharedAttempts != 0 || status.SharedTTFTSamples != 0 {
t.Fatalf("publisher imported its own events: %+v", status)
}
restarted := New(Options{})
restartedHistory := NewRedisHistory(HistoryOptions{Enabled: true, RedisURL: redisURL, Stream: stream, Instance: "restarted",
TTL: time.Minute, MaxEvents: 100, Logger: slog.New(slog.NewTextHandler(ioDiscard{}, nil))})
if restartedHistory == nil {
t.Fatal("restart history was not configured")
}
t.Cleanup(func() { _ = restartedHistory.Close() })
go restartedHistory.Run(ctx, restarted)
waitForSharedStatus(t, restarted, key, 1, 1)
}
func waitForSharedStatus(t *testing.T, tracker *Tracker, key RouteKey, attempts, ttft uint64) {
t.Helper()
deadline := time.Now().Add(5 * time.Second)
for time.Now().Before(deadline) {
status, found := tracker.StatusFor(key)
if found && status.SharedAttempts >= attempts && status.SharedTTFTSamples >= ttft {
return
}
time.Sleep(25 * time.Millisecond)
}
status, _ := tracker.StatusFor(key)
t.Fatalf("shared status did not converge: %+v", status)
}
type ioDiscard struct{}
func (ioDiscard) Write(data []byte) (int, error) { return len(data), nil }
func TestTrackerConcurrentObservations(t *testing.T) {
tracker := New(Options{FailureThreshold: 1000})
key := RouteKey{ModelID: "model", ProviderID: "provider", WireAPI: "chat_completions"}
var group sync.WaitGroup
for index := range 200 {
group.Add(1)
go func(failed bool) {
defer group.Done()
tracker.Observe(key, Observation{StatusCode: 200, Latency: time.Millisecond, Failed: failed})
}(index%2 == 0)
}
group.Wait()
snapshot := tracker.Snapshot()
if len(snapshot) != 1 || snapshot[0].Attempts != 200 || snapshot[0].RecentSamples != recentWindow || snapshot[0].AvailabilityPercent < 0 || snapshot[0].AvailabilityPercent > 100 {
t.Fatalf("unexpected concurrent snapshot: %+v", snapshot)
}
}
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