v2 plan: fake upstream answers /props without counting it (task 01 replacement helper); note the finding

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

docs/plans/v2/01-props.md

@@ -20,6 +20,7 @@ bytes as for the other endpoints.
 ## Files
 
 - Copy: `internal/health/props_test.go`
+- Copy (**replaces** v1's): `internal/proxy/helpers_test.go` — the fake upstream now answers `/props` without counting it as a hit, so the v1 proxy tests' exact hit counts still hold once the poller asks for it
 - Modify: `internal/health/health.go`, `internal/admin/admin.go` (or wherever `HostView` is built), `docs/implementer-log.md`
 
 ## Interfaces
@@ -49,13 +50,14 @@ Rules the tests check:
 
 ## Steps
 
-- [ ] **1.** `git switch master && git switch -c v2`; `cp docs/plans/v2/_files/internal/health/props_test.go internal/health/`.
+- [ ] **1.** `git switch master && git switch -c v2`; `cp docs/plans/v2/_files/internal/health/props_test.go internal/health/`;
+  `cp docs/plans/v2/_files/internal/proxy/helpers_test.go internal/proxy/`.
 - [ ] **2. See it fail** (compile: `NCtx` undefined). **3. Write the code.** `gofmt -w internal/`.
 - [ ] **4.** `go test -race -count=1 ./internal/health/ ./internal/admin/` → both `ok`.
 - [ ] **5.** `make gate` → `gate: ok`. **6.** Row `v2/01-props`; commit.
 
 ```sh
-git add internal/health internal/admin docs/implementer-log.md
+git add internal/health internal/admin internal/proxy/helpers_test.go docs/implementer-log.md
 git commit
 ```
 

docs/plans/v2/README.md

@@ -52,3 +52,12 @@ reason.
    the same peer; a wake target whose broadcast address is unroutable (503 within `wait`, no
    hang); the guard with a body of exactly `MaxBody`.
 4. Findings under "Reviews" in `docs/implementer-log.md`, by fault.
+
+## Changes during the run
+
+- 2026-09-25, task 01: the new `/props` poll lands on the v1 fake upstream's `/` catch-all, which
+  counts hits, so two v1 proxy tests with exact hit counts failed. Ornith implemented the task
+  correctly, did not touch the protected file, and stopped with a `stopped` row — exactly the
+  procedure. Owner's fault (T19 once more: a new task changed what an earlier given file
+  measures, and the pre-handover walk missed it). `helpers_test.go` is now a v2 given file that
+  answers `/props` without counting it; resumed.

docs/plans/v2/_files/internal/proxy/helpers_test.go

@@ -0,0 +1,216 @@
+package proxy_test
+
+// Test scaffolding shared by proxy_test.go and recorder_test.go: the fake health table, the fake
+// llama-server upstream, and the rig that builds a whole crossbar over real HTTP.
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"path/filepath"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"git.wntrmute.dev/kyle/crossbar/internal/config"
+	"git.wntrmute.dev/kyle/crossbar/internal/health"
+	"git.wntrmute.dev/kyle/crossbar/internal/lease"
+	"git.wntrmute.dev/kyle/crossbar/internal/limiter"
+	"git.wntrmute.dev/kyle/crossbar/internal/proxy"
+	"git.wntrmute.dev/kyle/crossbar/internal/store"
+)
+
+// fakeHealth is a hand-set health table that also records MarkDown calls. It lived in the v0
+// proxy_test.go; the v1 given test replaces that file, so recorder_test.go (which still exercises
+// the nil-lease path through proxy.New) needs it here.
+type fakeHealth struct {
+	mu     sync.Mutex
+	st     map[string]health.Status
+	marked []string
+}
+
+func (f *fakeHealth) Get(name string) (health.Status, bool) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	s, ok := f.st[name]
+	return s, ok
+}
+
+func (f *fakeHealth) MarkDown(name, reason string) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.marked = append(f.marked, name)
+	s := f.st[name]
+	s.Healthy = false
+	s.LastErr = reason
+	f.st[name] = s
+}
+
+func (f *fakeHealth) markedHosts() []string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return append([]string{}, f.marked...)
+}
+
+// upstream is a llama-server stand-in: streams N chunks with a delay, reports usage/timings in
+// the final chunk, counts requests, and can be slowed down or killed.
+type upstream struct {
+	name  string
+	srv   *httptest.Server
+	hits  atomic.Int32
+	delay time.Duration
+	mu    sync.Mutex
+	last  recorded
+}
+
+type recorded struct{ method, path, host, xff, body string }
+
+func newUpstream(t *testing.T, name string) *upstream {
+	u := &upstream{name: name}
+	mux := http.NewServeMux()
+	mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, `{"status":"ok"}`) })
+	mux.HandleFunc("/v1/models", func(w http.ResponseWriter, r *http.Request) {
+		u.mu.Lock()
+		u.last = recorded{r.Method, r.URL.RequestURI(), r.Host, r.Header.Get("X-Forwarded-For"), ""}
+		u.mu.Unlock()
+		fmt.Fprint(w, `{"object":"list","data":[{"id":"shared"},{"id":"`+name+`-only"}]}`)
+	})
+	// The v2 poller also asks /props; it is a health request, not a hit, so it is not counted.
+	// No n_ctx here: "unknown context" is what the v1 tests and TestUnknownContextNeverBlocks want.
+	mux.HandleFunc("/props", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprint(w, `{"model_path":"`+name+`"}`)
+	})
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		u.hits.Add(1)
+		b, _ := io.ReadAll(r.Body)
+		u.mu.Lock()
+		u.last = recorded{r.Method, r.URL.RequestURI(), r.Host, r.Header.Get("X-Forwarded-For"), string(b)}
+		u.mu.Unlock()
+		var req struct {
+			Stream bool `json:"stream"`
+		}
+		_ = json.Unmarshal(b, &req)
+		w.Header().Set("X-Upstream", name)
+		time.Sleep(u.delay)
+		if !req.Stream {
+			w.Header().Set("Content-Type", "application/json")
+			fmt.Fprintf(w, `{"choices":[{"message":{"role":"assistant","content":"hi from %s"}}],"usage":{"prompt_tokens":100,"completion_tokens":10,"total_tokens":110},"timings":{"prompt_n":100,"cache_n":90,"predicted_n":10,"predicted_ms":50.0}}`, name)
+			return
+		}
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.WriteHeader(200)
+		fl := w.(http.Flusher)
+		for i := 0; i < 3; i++ {
+			fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"content\":\"%s %d \"}}]}\n\n", name, i)
+			fl.Flush()
+			time.Sleep(10 * time.Millisecond)
+		}
+		fmt.Fprint(w, `data: {"choices":[],"usage":{"prompt_tokens":200,"completion_tokens":20,"total_tokens":220},"timings":{"prompt_n":200,"cache_n":150,"predicted_n":20,"predicted_ms":80.0}}`+"\n\n")
+		fl.Flush()
+		fmt.Fprint(w, "data: [DONE]\n\n")
+	})
+	u.srv = httptest.NewServer(mux)
+	t.Cleanup(u.srv.Close)
+	return u
+}
+
+func (u *upstream) lastReq() recorded { u.mu.Lock(); defer u.mu.Unlock(); return u.last }
+
+// rig is one crossbar: config, real health table (polled once), real lease table over a real
+// SQLite store, real limiter, the proxy handler served by httptest.
+type rig struct {
+	t      *testing.T
+	cfg    *config.Config
+	health *health.Table
+	store  *store.Store
+	leases *lease.Table
+	lim    *limiter.Limiter
+	front  *httptest.Server
+}
+
+// newRig builds crossbar from a config text where %s placeholders are the upstream base URLs.
+func newRig(t *testing.T, cfgText string, ups ...*upstream) *rig {
+	urls := make([]any, len(ups))
+	for i, u := range ups {
+		urls[i] = u.srv.URL
+	}
+	cfg, err := config.Parse(strings.NewReader(fmt.Sprintf(cfgText, urls...)))
+	if err != nil {
+		t.Fatal(err)
+	}
+	bases := map[string]string{}
+	for name, h := range cfg.Hosts {
+		bases[name] = h.BaseURL
+	}
+	ht := health.New(bases, time.Hour, nil)
+	ht.PollOnce(t.Context())
+	st, err := store.Open(filepath.Join(t.TempDir(), "crossbar.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = st.Close() })
+	lim := limiter.New()
+	for name, h := range cfg.Hosts {
+		for model, m := range h.Models {
+			lim.Configure(name, model, m.Parallel, cfg.QueueMax)
+		}
+	}
+	lt, err := lease.New(st, proxy.HostView(ht, cfg), proxy.Chooser(cfg, ht, lim), cfg.LeaseIdle.Duration)
+	if err != nil {
+		t.Fatal(err)
+	}
+	p := proxy.New(cfg, ht, lt, lim, st, nil)
+	front := httptest.NewServer(p)
+	t.Cleanup(front.Close)
+	return &rig{t: t, cfg: cfg, health: ht, store: st, leases: lt, lim: lim, front: front}
+}
+
+const twoHosts = `
+listen = "127.0.0.1:1"
+queue_max = 1
+lease_idle = "30m"
+[hosts.alpha]
+base_url = %q
+weight = 1.0
+models = { "shared" = { parallel = 2 }, "alpha-only" = { } }
+[hosts.beta]
+base_url = %q
+weight = 2.0
+models = { "shared" = { parallel = 2 }, "beta-only" = { } }
+[routes.r]
+hosts = ["alpha", "beta"]
+default_model = "shared"
+[routes.other]
+hosts = ["alpha"]
+`
+
+func conversation(id, turn int) string {
+	msgs := fmt.Sprintf(`{"role":"system","content":"project"},{"role":"user","content":"conversation %d opening"}`, id)
+	for i := 1; i < turn; i++ {
+		msgs += fmt.Sprintf(`,{"role":"assistant","content":"ok"},{"role":"user","content":"turn %d"}`, i)
+	}
+	return `{"model":"shared","stream":false,"messages":[` + msgs + `]}`
+}
+
+func (r *rig) post(path, body string, hdr ...string) *http.Response {
+	req, _ := http.NewRequest(http.MethodPost, r.front.URL+path, strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	for i := 0; i+1 < len(hdr); i += 2 {
+		req.Header.Set(hdr[i], hdr[i+1])
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		r.t.Fatal(err)
+	}
+	return resp
+}
+
+func drain(resp *http.Response) string {
+	b, _ := io.ReadAll(resp.Body)
+	resp.Body.Close()
+	return string(b)
+}