v0 plan: move given files to _files/ so go vet ./... ignores them; note the first-attempt finding

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/plans/v0/_files/internal/health/health_test.go

@@ -0,0 +1,154 @@
+package health_test
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"git.wntrmute.dev/kyle/crossbar/internal/health"
+)
+
+// fake is a llama-server stand-in whose /health can be flipped and whose model list is fixed.
+type fake struct {
+	srv    *httptest.Server
+	down   atomic.Bool
+	models []string
+	hits   atomic.Int32
+}
+
+func newFake(t *testing.T, models ...string) *fake {
+	f := &fake{models: models}
+	mux := http.NewServeMux()
+	mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
+		f.hits.Add(1)
+		if f.down.Load() {
+			http.Error(w, "loading", http.StatusServiceUnavailable)
+			return
+		}
+		_, _ = w.Write([]byte(`{"status":"ok"}`))
+	})
+	mux.HandleFunc("/v1/models", func(w http.ResponseWriter, r *http.Request) {
+		type m struct {
+			ID string `json:"id"`
+		}
+		var data []m
+		for _, id := range f.models {
+			data = append(data, m{ID: id})
+		}
+		_ = json.NewEncoder(w).Encode(map[string]any{"object": "list", "data": data})
+	})
+	f.srv = httptest.NewServer(mux)
+	t.Cleanup(f.srv.Close)
+	return f
+}
+
+func TestFirstPollMakesHealthy(t *testing.T) {
+	a := newFake(t, "zeta", "alpha", "alpha")
+	tbl := health.New(map[string]string{"a": a.srv.URL}, time.Hour, nil)
+	if s, ok := tbl.Get("a"); !ok || s.Healthy || len(s.Loaded) != 0 {
+		t.Fatalf("before any poll: %+v %v", s, ok)
+	}
+	tbl.PollOnce(context.Background())
+	s, _ := tbl.Get("a")
+	if !s.Healthy || s.Consecutive != 1 || s.LastErr != "" || s.LastOK.IsZero() {
+		t.Errorf("after one good poll: %+v", s)
+	}
+	if len(s.Loaded) != 2 || s.Loaded[0] != "alpha" || s.Loaded[1] != "zeta" {
+		t.Errorf("Loaded = %v, want sorted, unique [alpha zeta]", s.Loaded)
+	}
+}
+
+func TestFailureThenRecoveryNeedsTwoPolls(t *testing.T) {
+	a := newFake(t, "m")
+	tbl := health.New(map[string]string{"a": a.srv.URL}, time.Hour, nil)
+	ctx := context.Background()
+	tbl.PollOnce(ctx)
+	a.down.Store(true)
+	tbl.PollOnce(ctx)
+	s, _ := tbl.Get("a")
+	if s.Healthy || s.Consecutive != 0 || s.LastErr == "" {
+		t.Fatalf("after failure: %+v", s)
+	}
+	if len(s.Loaded) != 1 {
+		t.Errorf("Loaded is left as last seen; got %v", s.Loaded)
+	}
+	a.down.Store(false)
+	tbl.PollOnce(ctx)
+	if s, _ := tbl.Get("a"); s.Healthy || s.Consecutive != 1 {
+		t.Errorf("one good poll after a failure must not be healthy yet: %+v", s)
+	}
+	tbl.PollOnce(ctx)
+	if s, _ := tbl.Get("a"); !s.Healthy || s.Consecutive != 2 || s.LastErr != "" {
+		t.Errorf("two good polls: %+v", s)
+	}
+}
+
+func TestMarkDown(t *testing.T) {
+	a := newFake(t, "m")
+	tbl := health.New(map[string]string{"a": a.srv.URL}, time.Hour, nil)
+	tbl.PollOnce(context.Background())
+	tbl.MarkDown("a", "connection refused")
+	s, _ := tbl.Get("a")
+	if s.Healthy || s.Consecutive != 0 || s.LastErr != "marked down: connection refused" {
+		t.Errorf("after MarkDown: %+v", s)
+	}
+	tbl.MarkDown("nobody", "x") // unknown hosts are ignored, not a panic
+	tbl.PollOnce(context.Background())
+	if s, _ := tbl.Get("a"); s.Healthy {
+		t.Errorf("one poll after MarkDown must not be healthy: %+v", s)
+	}
+}
+
+func TestUnreachableAndUnknown(t *testing.T) {
+	tbl := health.New(map[string]string{"a": "http://127.0.0.1:1"}, time.Hour, &http.Client{Timeout: time.Second})
+	tbl.PollOnce(context.Background())
+	s, ok := tbl.Get("a")
+	if !ok || s.Healthy || s.LastErr == "" {
+		t.Errorf("unreachable host: %+v %v", s, ok)
+	}
+	if _, ok := tbl.Get("zzz"); ok {
+		t.Errorf("unknown host must report ok=false")
+	}
+}
+
+func TestAllIsACopy(t *testing.T) {
+	a := newFake(t, "m")
+	tbl := health.New(map[string]string{"a": a.srv.URL}, time.Hour, nil)
+	tbl.PollOnce(context.Background())
+	all := tbl.All()
+	all["a"].Loaded[0] = "changed"
+	if s, _ := tbl.Get("a"); s.Loaded[0] != "m" {
+		t.Errorf("All must return copies")
+	}
+	if len(all) != 1 {
+		t.Errorf("All = %v", all)
+	}
+}
+
+func TestRunPollsOnStart(t *testing.T) {
+	a := newFake(t, "m")
+	tbl := health.New(map[string]string{"a": a.srv.URL}, 20*time.Millisecond, nil)
+	ctx, cancel := context.WithCancel(context.Background())
+	done := make(chan struct{})
+	go func() { tbl.Run(ctx); close(done) }()
+	deadline := time.Now().Add(2 * time.Second)
+	for a.hits.Load() < 3 && time.Now().Before(deadline) {
+		time.Sleep(5 * time.Millisecond)
+	}
+	cancel()
+	select {
+	case <-done:
+	case <-time.After(time.Second):
+		t.Fatal("Run did not return after cancel")
+	}
+	if a.hits.Load() < 3 {
+		t.Errorf("Run polled %d times in 2s at 20ms interval", a.hits.Load())
+	}
+	if s, _ := tbl.Get("a"); !s.Healthy {
+		t.Errorf("not healthy after Run: %+v", s)
+	}
+}