fix(#76): prevent false-fresh aggregate responses

internal/api/client.go

@@ -1,6 +1,7 @@
 package api
 
 import (
+	"context"
 	"net/http"
 	"sync"
 	"sync/atomic"
@@ -26,8 +27,12 @@ type requestPacer struct {
 
 // wait blocks until this caller's reserved slot arrives.
 func (p *requestPacer) wait() {
+	_ = p.waitContext(context.Background())
+}
+
+func (p *requestPacer) waitContext(ctx context.Context) error {
 	if p == nil || p.interval <= 0 {
-		return
+		return nil
 	}
 	p.mu.Lock()
 	now := time.Now()
@@ -38,8 +43,20 @@ func (p *requestPacer) wait() {
 	p.next = p.next.Add(p.interval)
 	p.mu.Unlock()
 	if sleep > 0 {
-		time.Sleep(sleep)
+		timer := time.NewTimer(sleep)
+		defer timer.Stop()
+		select {
+		case <-timer.C:
+		case <-ctx.Done():
+			// Return the unused reservation so repeated bounded enrichment
+			// cancellations do not leave pacing debt for later real requests.
+			p.mu.Lock()
+			p.next = p.next.Add(-p.interval)
+			p.mu.Unlock()
+			return ctx.Err()
+		}
 	}
+	return nil
 }
 
 type OpenF1Client struct {

internal/api/openf1.go

@@ -2,6 +2,7 @@ package api
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -59,8 +60,14 @@ func retryAfter429(resp *http.Response) time.Duration {
 // Without this, concurrent fan-outs (championship hub, track prefetch) burst
 // past the free-tier limit and callers silently treat 429s as missing data.
 func (c *OpenF1Client) doPaced(req *http.Request) (*http.Response, error) {
+	return c.doPacedContext(req.Context(), req)
+}
+
+func (c *OpenF1Client) doPacedContext(ctx context.Context, req *http.Request) (*http.Response, error) {
 	for attempt := 0; ; attempt++ {
-		c.pacer.wait()
+		if err := c.pacer.waitContext(ctx); err != nil {
+			return nil, err
+		}
 		resp, err := c.httpClient.Do(req)
 		if err != nil {
 			return nil, err
@@ -70,7 +77,14 @@ func (c *OpenF1Client) doPaced(req *http.Request) (*http.Response, error) {
 		}
 		delay := retryAfter429(resp)
 		resp.Body.Close()
-		time.Sleep(delay)
+		timer := time.NewTimer(delay)
+		select {
+		case <-timer.C:
+		case <-ctx.Done():
+			timer.Stop()
+			return nil, ctx.Err()
+		}
+		timer.Stop()
 	}
 }
 
@@ -83,13 +97,23 @@ func (c *OpenF1Client) doPaced(req *http.Request) (*http.Response, error) {
 // entry for this URL, that stale entry is returned instead of propagating the
 // error.  The client's staleFlag is set so the UI can show a disclaimer.
 func (c *OpenF1Client) get(url string) (io.ReadCloser, error) {
+	return c.getContext(context.Background(), url)
+}
+
+// getContext is the cancellable form used by bounded optional web enrichment.
+// A caller cancellation never falls back to stale data: the work is no longer
+// relevant to that response and must stop instead of continuing in background.
+func (c *OpenF1Client) getContext(ctx context.Context, url string) (io.ReadCloser, error) {
+	if err := ctx.Err(); err != nil {
+		return nil, err
+	}
 	// 1. Check the cache for a fresh (non-expired) entry.
 	if cachedData, ok := c.cache.Get(url); ok {
 		return io.NopCloser(bytes.NewReader(cachedData)), nil
 	}
 
 	// 2. Attempt a live network request.
-	req, err := http.NewRequest("GET", url, nil)
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
 	if err != nil {
 		// Even a request-construction failure warrants a stale fallback.
 		return c.tryStale(url, err)
@@ -98,8 +122,11 @@ func (c *OpenF1Client) get(url string) (io.ReadCloser, error) {
 		req.Header.Set("Authorization", "Bearer "+c.apiKey)
 	}
 
-	resp, err := c.doPaced(req)
+	resp, err := c.doPacedContext(ctx, req)
 	if err != nil {
+		if ctx.Err() != nil {
+			return nil, ctx.Err()
+		}
 		return c.tryStale(url, err)
 	}
 	defer resp.Body.Close()
@@ -128,6 +155,9 @@ func (c *OpenF1Client) get(url string) (io.ReadCloser, error) {
 	// 3. Success — read the body, store in cache, return.
 	data, err := io.ReadAll(resp.Body)
 	if err != nil {
+		if ctx.Err() != nil {
+			return nil, ctx.Err()
+		}
 		return c.tryStale(url, err)
 	}
 
@@ -245,7 +275,13 @@ func (c *OpenF1Client) GetDriversForSession(sessionKey int) ([]models.Driver, er
 }
 
 func (c *OpenF1Client) GetDriver(sessionKey, driverNumber int) (*models.Driver, error) {
-	body, err := c.get(fmt.Sprintf("%s/v1/drivers?session_key=%d&driver_number=%d", c.url, sessionKey, driverNumber))
+	return c.GetDriverContext(context.Background(), sessionKey, driverNumber)
+}
+
+// GetDriverContext is a cancellable single-driver lookup for optional bounded
+// enrichment. Other public methods retain their existing background semantics.
+func (c *OpenF1Client) GetDriverContext(ctx context.Context, sessionKey, driverNumber int) (*models.Driver, error) {
+	body, err := c.getContext(ctx, fmt.Sprintf("%s/v1/drivers?session_key=%d&driver_number=%d", c.url, sessionKey, driverNumber))
 	if err != nil {
 		return nil, err
 	}

internal/api/pacing_test.go

@@ -1,6 +1,7 @@
 package api
 
 import (
+	"context"
 	"encoding/json"
 	"io"
 	"net/http"
@@ -49,6 +50,28 @@ func TestRequestPacerNilSafe(t *testing.T) {
 	p.wait() // must not panic
 }
 
+func TestRequestPacerCancellationReturnsUnusedReservation(t *testing.T) {
+	p := &requestPacer{interval: 100 * time.Millisecond}
+	if err := p.waitContext(context.Background()); err != nil {
+		t.Fatal(err)
+	}
+	p.mu.Lock()
+	wantNext := p.next
+	p.mu.Unlock()
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Millisecond)
+	defer cancel()
+	if err := p.waitContext(ctx); err == nil {
+		t.Fatal("expected paced wait cancellation")
+	}
+	p.mu.Lock()
+	gotNext := p.next
+	p.mu.Unlock()
+	if !gotNext.Equal(wantNext) {
+		t.Fatalf("cancelled reservation left pacing debt: next %v, want %v", gotNext, wantNext)
+	}
+}
+
 func TestGetRetriesOn429(t *testing.T) {
 	var calls atomic.Int32
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

internal/web/api.go

@@ -324,12 +324,13 @@ func (s *Server) handleResults(w http.ResponseWriter, r *http.Request) {
 		results    []models.SessionResult
 		drivers    []models.Driver
 		resultsErr error
+		driversErr error
 		wg         sync.WaitGroup
 	)
 	client := s.client.Scoped()
 	wg.Add(2)
 	go func() { defer wg.Done(); results, resultsErr = client.GetSessionResult(sessionKey) }()
-	go func() { defer wg.Done(); drivers, _ = client.GetDriversForSession(sessionKey) }()
+	go func() { defer wg.Done(); drivers, driversErr = client.GetDriversForSession(sessionKey) }()
 	wg.Wait()
 
 	if resultsErr != nil {
@@ -338,18 +339,27 @@ func (s *Server) handleResults(w http.ResponseWriter, r *http.Request) {
 	}
 
 	driverMap := buildDriverMap(drivers)
+	incomplete := driversErr != nil
 	enriched := make([]resultWithDriver, 0, len(results))
 	for _, res := range results {
 		e := resultWithDriver{SessionResult: res}
-		if d, ok := driverMap[res.DriverNumber]; ok {
+		if d, ok := driverMap[res.DriverNumber]; ok && hasDriverPresentation(d) {
 			e.NameAcronym = d.NameAcronym
 			e.FullName = d.FullName
 			e.TeamName = d.TeamName
 			e.TeamColour = d.TeamColour
+		} else {
+			incomplete = true
 		}
 		enriched = append(enriched, e)
 	}
-	markOpenF1Response(w, client)
+	resultsFreshness := "fresh"
+	if len(results) == 0 {
+		resultsFreshness = "limited"
+	} else if incomplete {
+		resultsFreshness = "partial"
+	}
+	markOpenF1Availability(w, client, resultsFreshness)
 	writeJSON(w, enriched)
 }
 
@@ -400,15 +410,16 @@ func (s *Server) handleGrid(w http.ResponseWriter, r *http.Request) {
 	}
 
 	var (
-		grid    []models.StartingGrid
+		grid       []models.StartingGrid
-		drivers []models.Driver
+		drivers    []models.Driver
-		gridErr error
+		gridErr    error
-		wg      sync.WaitGroup
+		driversErr error
+		wg         sync.WaitGroup
 	)
 	client := s.client.Scoped()
 	wg.Add(2)
 	go func() { defer wg.Done(); grid, gridErr = client.GetStartingGrid(sessionKey) }()
-	go func() { defer wg.Done(); drivers, _ = client.GetDriversForSession(sessionKey) }()
+	go func() { defer wg.Done(); drivers, driversErr = client.GetDriversForSession(sessionKey) }()
 	wg.Wait()
 
 	if gridErr != nil {
@@ -417,18 +428,27 @@ func (s *Server) handleGrid(w http.ResponseWriter, r *http.Request) {
 	}
 
 	driverMap := buildDriverMap(drivers)
+	incomplete := driversErr != nil
 	enriched := make([]gridWithDriver, 0, len(grid))
 	for _, g := range grid {
 		e := gridWithDriver{StartingGrid: g}
-		if d, ok := driverMap[g.DriverNumber]; ok {
+		if d, ok := driverMap[g.DriverNumber]; ok && hasDriverPresentation(d) {
 			e.NameAcronym = d.NameAcronym
 			e.FullName = d.FullName
 			e.TeamName = d.TeamName
 			e.TeamColour = d.TeamColour
+		} else {
+			incomplete = true
 		}
 		enriched = append(enriched, e)
 	}
-	markOpenF1Response(w, client)
+	gridFreshness := "fresh"
+	if len(grid) == 0 {
+		gridFreshness = "limited"
+	} else if incomplete {
+		gridFreshness = "partial"
+	}
+	markOpenF1Availability(w, client, gridFreshness)
 	writeJSON(w, enriched)
 }
 
@@ -589,27 +609,30 @@ func (s *Server) handleChampionshipDrivers(w http.ResponseWriter, r *http.Reques
 		return
 	}
 	if len(champ) == 0 {
-		markOpenF1Response(w, client)
+		markOpenF1Availability(w, client, "limited")
 		writeJSON(w, []any{})
 		return
 	}
 
-	drivers, _ := client.GetDriversForSession(champ[0].SessionKey)
+	drivers, driversErr := client.GetDriversForSession(champ[0].SessionKey)
 	driverMap := buildDriverMapFirst(drivers)
+	incomplete := driversErr != nil
 
 	enriched := make([]champDriverWithInfo, 0, len(champ))
 	for _, c := range champ {
 		e := champDriverWithInfo{ChampionshipDriver: c}
 		d, ok := championshipDriverInfo(client, c.SessionKey, c.DriverNumber, driverMap)
-		if ok {
+		if ok && hasDriverPresentation(d) {
 			e.NameAcronym = d.NameAcronym
 			e.FullName = d.FullName
 			e.TeamName = d.TeamName
 			e.TeamColour = d.TeamColour
+		} else {
+			incomplete = true
 		}
 		enriched = append(enriched, e)
 	}
-	markOpenF1Response(w, client)
+	markOpenF1AggregateResponse(w, client, incomplete)
 	writeJSON(w, enriched)
 }
 
@@ -634,7 +657,11 @@ func (s *Server) handleChampionshipTeams(w http.ResponseWriter, r *http.Request)
 		writeError(w, err, http.StatusInternalServerError, client.LastResponseWasStale())
 		return
 	}
-	markOpenF1Response(w, client)
+	if len(teams) == 0 {
+		markOpenF1Availability(w, client, "limited")
+	} else {
+		markOpenF1Response(w, client)
+	}
 	writeJSON(w, teams)
 }
 
@@ -864,20 +891,29 @@ func (s *Server) openF1ChampionshipHub(client *api.OpenF1Client, year int) (cham
 		return champHubResponse{}, false, err
 	}
 	if len(champ) == 0 {
-		return champHubResponse{Season: year, RoundLabels: []string{}, Drivers: []champHubDriver{}, Teams: []champHubTeam{}}, false, nil
+		return champHubResponse{Season: year, RoundLabels: []string{}, Drivers: []champHubDriver{}, Teams: []champHubTeam{}}, true, nil
 	}
 	teams, teamsErr := client.GetTeamChampionshipForYear(year)
 
 	driverInfo := map[int]models.Driver{}
+	driversIncomplete := false
 	if ds, derr := client.GetDriversForSession(champ[0].SessionKey); derr == nil {
 		driverInfo = buildDriverMapFirst(ds)
+	} else {
+		driversIncomplete = true
+	}
+	for _, standing := range champ {
+		if !hasDriverPresentation(driverInfo[standing.DriverNumber]) {
+			driversIncomplete = true
+			break
+		}
 	}
 
 	races, incomplete, err := fetchSeasonRaces(client, year)
 	if err != nil {
 		return champHubResponse{}, false, err
 	}
-	incomplete = incomplete || teamsErr != nil
+	incomplete = incomplete || teamsErr != nil || driversIncomplete
 
 	resp := aggregateChampionshipHub(year, races, champ, teams, driverInfo)
 	ttl := champHubTTL(year, time.Now())
@@ -923,7 +959,11 @@ func fetchSeasonRaces(client *api.OpenF1Client, year int) (races []meetingRace,
 			}
 		}
 		if raceKey == 0 {
-			return meetingRace{}, false // not a GP meeting (e.g. pre-season testing)
+			failed.Store(true)
+			// The meeting list does not identify non-championship events. Skipping
+			// a meeting without a Race may be expected (testing), but the aggregate
+			// is not proven complete and must be labelled partial.
+			return meetingRace{}, false
 		}
 		results, rerr := client.GetSessionResult(raceKey)
 		grid, gerr := client.GetStartingGrid(raceKey)
@@ -1342,23 +1382,25 @@ func (s *Server) handleStrategy(w http.ResponseWriter, r *http.Request) {
 	}
 
 	var (
-		stints    []models.Stint
+		stints     []models.Stint
-		pits      []models.Pit
+		pits       []models.Pit
-		results   []models.SessionResult
+		results    []models.SessionResult
-		drivers   []models.Driver
+		drivers    []models.Driver
-		rc        []models.RaceControl
+		rc         []models.RaceControl
-		stintsErr error
+		stintsErr  error
-		pitsErr   error
+		pitsErr    error
-		resErr    error
+		resErr     error
-		wg        sync.WaitGroup
+		driversErr error
+		rcErr      error
+		wg         sync.WaitGroup
 	)
 	client := s.client.Scoped()
 	wg.Add(5)
 	go func() { defer wg.Done(); stints, stintsErr = client.GetStintsForSession(sessionKey) }()
 	go func() { defer wg.Done(); pits, pitsErr = client.GetPitStopsForSession(sessionKey) }()
 	go func() { defer wg.Done(); results, resErr = client.GetSessionResult(sessionKey) }()
-	go func() { defer wg.Done(); drivers, _ = client.GetDriversForSession(sessionKey) }()
+	go func() { defer wg.Done(); drivers, driversErr = client.GetDriversForSession(sessionKey) }()
-	go func() { defer wg.Done(); rc, _ = client.GetRaceControl(sessionKey) }()
+	go func() { defer wg.Done(); rc, rcErr = client.GetRaceControl(sessionKey) }()
 	wg.Wait()
 
 	if stintsErr != nil || pitsErr != nil || resErr != nil {
@@ -1375,12 +1417,13 @@ func (s *Server) handleStrategy(w http.ResponseWriter, r *http.Request) {
 
 	// Non-race sessions have no stints.
 	if len(stints) == 0 {
-		markOpenF1Response(w, client)
+		markOpenF1AggregateResponse(w, client, driversErr != nil || rcErr != nil)
 		writeJSON(w, map[string]any{"note": "Not applicable", "drivers": []any{}})
 		return
 	}
 
 	driverMap := buildDriverMap(drivers)
+	incomplete := driversErr != nil || rcErr != nil
 
 	resultMap := make(map[int]models.SessionResult, len(results))
 	totalLaps := 0
@@ -1413,6 +1456,9 @@ func (s *Server) handleStrategy(w http.ResponseWriter, r *http.Request) {
 	stratDrivers := make([]strategyDriver, 0, len(seenDrivers))
 	for dn := range seenDrivers {
 		d := driverMap[dn]
+		if !hasDriverPresentation(d) {
+			incomplete = true
+		}
 		res := resultMap[dn]
 
 		sd := strategyDriver{
@@ -1467,7 +1513,7 @@ func (s *Server) handleStrategy(w http.ResponseWriter, r *http.Request) {
 		return pi < pj
 	})
 
-	markOpenF1Response(w, client)
+	markOpenF1AggregateResponse(w, client, incomplete)
 	writeJSON(w, strategyResponse{
 		SessionKey: sessionKey,
 		TotalLaps:  totalLaps,
@@ -1563,22 +1609,31 @@ func (s *Server) handleLapsComparison(w http.ResponseWriter, r *http.Request) {
 	}
 
 	var (
-		allLaps []models.Lap
+		allLaps   []models.Lap
-		stints  []models.Stint
+		stints    []models.Stint
-		pits    []models.Pit
+		pits      []models.Pit
-		rc      []models.RaceControl
+		rc        []models.RaceControl
-		wg      sync.WaitGroup
+		lapsErr   error
+		stintsErr error
+		pitsErr   error
+		rcErr     error
+		wg        sync.WaitGroup
 	)
 	client := s.client.Scoped()
 	wg.Add(4)
-	go func() { defer wg.Done(); allLaps, _ = client.GetLapsForSession(sessionKey) }()
+	go func() { defer wg.Done(); allLaps, lapsErr = client.GetLapsForSession(sessionKey) }()
-	go func() { defer wg.Done(); stints, _ = client.GetStintsForSession(sessionKey) }()
+	go func() { defer wg.Done(); stints, stintsErr = client.GetStintsForSession(sessionKey) }()
-	go func() { defer wg.Done(); pits, _ = client.GetPitStopsForSession(sessionKey) }()
+	go func() { defer wg.Done(); pits, pitsErr = client.GetPitStopsForSession(sessionKey) }()
-	go func() { defer wg.Done(); rc, _ = client.GetRaceControl(sessionKey) }()
+	go func() { defer wg.Done(); rc, rcErr = client.GetRaceControl(sessionKey) }()
 	wg.Wait()
+	if lapsErr != nil {
+		writeError(w, lapsErr, http.StatusInternalServerError, client.LastResponseWasStale())
+		return
+	}
 
-	allDrivers, _ := client.GetDriversForSession(sessionKey)
+	allDrivers, driversErr := client.GetDriversForSession(sessionKey)
 	driverMap := buildDriverMap(allDrivers)
+	incomplete := stintsErr != nil || pitsErr != nil || rcErr != nil || driversErr != nil
 
 	// If no filter, default to first 3 unique driver numbers from lap data.
 	if len(requestedDrivers) == 0 {
@@ -1616,6 +1671,9 @@ func (s *Server) handleLapsComparison(w http.ResponseWriter, r *http.Request) {
 	compDrivers := make([]comparisonDriver, 0, len(requestedDrivers))
 	for _, dn := range requestedDrivers {
 		d := driverMap[dn]
+		if !hasDriverPresentation(d) {
+			incomplete = true
+		}
 		cd := comparisonDriver{
 			DriverNumber: dn,
 			NameAcronym:  d.NameAcronym,
@@ -1631,7 +1689,13 @@ func (s *Server) handleLapsComparison(w http.ResponseWriter, r *http.Request) {
 		compDrivers = append(compDrivers, cd)
 	}
 
-	markOpenF1Response(w, client)
+	freshness := "fresh"
+	if len(allLaps) == 0 {
+		freshness = "limited"
+	} else if incomplete {
+		freshness = "partial"
+	}
+	markOpenF1Availability(w, client, freshness)
 	writeJSON(w, lapsComparisonResponse{
 		SessionKey: sessionKey,
 		SCPeriods:  extractSCPeriods(rc),

internal/web/championship_hub_test.go

@@ -1,13 +1,91 @@
 package web
 
 import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
 	"sync/atomic"
 	"testing"
 	"time"
 
+	"github.com/AmanTahiliani/box-box/internal/api"
 	"github.com/AmanTahiliani/box-box/internal/models"
 )
 
+func championshipTestUpstream(t *testing.T, driversOK, meetingHasRace bool) *httptest.Server {
+	t.Helper()
+	completed := time.Now().Add(-time.Hour).UTC().Format(time.RFC3339)
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch r.URL.Path {
+		case "/v1/sessions":
+			if r.URL.Query().Get("session_name") == "Race" {
+				_, _ = fmt.Fprintf(w, `[{"session_key":99,"session_name":"Race","date_end":%q}]`, completed)
+				return
+			}
+			if meetingHasRace {
+				_, _ = w.Write([]byte(`[{"session_key":101,"meeting_key":1,"session_name":"Race"}]`))
+			} else {
+				_, _ = w.Write([]byte(`[{"session_key":100,"meeting_key":1,"session_name":"Practice 1"}]`))
+			}
+		case "/v1/championship_drivers":
+			_, _ = w.Write([]byte(`[{"driver_number":1,"session_key":99,"position_current":1,"points_current":25}]`))
+		case "/v1/championship_teams":
+			_, _ = w.Write([]byte(`[{"team_name":"Red Bull","position_current":1,"points_current":25}]`))
+		case "/v1/drivers":
+			if !driversOK {
+				http.Error(w, "identity unavailable", http.StatusBadGateway)
+				return
+			}
+			_, _ = w.Write([]byte(`[{"driver_number":1,"name_acronym":"VER","full_name":"Max Verstappen","team_name":"Red Bull","team_colour":"3671c6"}]`))
+		case "/v1/meetings":
+			_, _ = w.Write([]byte(`[{"meeting_key":1,"meeting_name":"Test GP"}]`))
+		case "/v1/session_result":
+			_, _ = w.Write([]byte(`[{"driver_number":1,"position":1,"points":25}]`))
+		case "/v1/starting_grid":
+			_, _ = w.Write([]byte(`[{"driver_number":1,"position":1}]`))
+		default:
+			http.NotFound(w, r)
+		}
+	}))
+}
+
+func TestOpenF1ChampionshipHubIdentityFailureIsPartialAndCached(t *testing.T) {
+	upstream := championshipTestUpstream(t, false, true)
+	defer upstream.Close()
+	client := api.NewOpenF1Client(upstream.URL, 2*time.Second)
+	defer client.Close()
+	server := NewServer(client, 0, nil)
+	year := time.Now().Year()
+
+	_, incomplete, err := server.openF1ChampionshipHub(client.Scoped(), year)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !incomplete {
+		t.Fatal("missing championship driver identity was labelled complete")
+	}
+	_, source, freshness, ok := server.hubCache.getWithMetadata(year, time.Now())
+	if !ok || source != "openf1" || freshness != "partial" {
+		t.Fatalf("cached metadata = hit %v, %q/%q", ok, source, freshness)
+	}
+}
+
+func TestFetchSeasonRacesMeetingWithoutRaceIsIncomplete(t *testing.T) {
+	upstream := championshipTestUpstream(t, true, false)
+	defer upstream.Close()
+	client := api.NewOpenF1Client(upstream.URL, 2*time.Second)
+	defer client.Close()
+
+	races, incomplete, err := fetchSeasonRaces(client.Scoped(), time.Now().Year())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !incomplete || len(races) != 0 {
+		t.Fatalf("no-Race meeting = races %d, incomplete %v", len(races), incomplete)
+	}
+}
+
 func raceResult(num, pos int, pts float64) models.SessionResult {
 	return models.SessionResult{DriverNumber: num, Position: pos, Points: pts}
 }

internal/web/component_freshness_test.go

@@ -0,0 +1,107 @@
+package web
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/AmanTahiliani/box-box/internal/api"
+)
+
+func componentTestServer(t *testing.T, responses map[string]string, failures map[string]bool) *Server {
+	t.Helper()
+	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if failures[r.URL.Path] {
+			http.Error(w, "component unavailable", http.StatusBadGateway)
+			return
+		}
+		body, ok := responses[r.URL.Path]
+		if !ok {
+			http.NotFound(w, r)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(body))
+	}))
+	t.Cleanup(upstream.Close)
+	client := api.NewOpenF1Client(upstream.URL, 2*time.Second)
+	t.Cleanup(func() { _ = client.Close() })
+	return NewServer(client, 0, nil)
+}
+
+func assertAvailabilityHeaders(t *testing.T, recorder *httptest.ResponseRecorder, source, freshness string) {
+	t.Helper()
+	if recorder.Code != http.StatusOK || recorder.Header().Get(dataSourceHeader) != source || recorder.Header().Get(dataFreshnessHeader) != freshness {
+		t.Fatalf("response = status %d, metadata %q/%q, body=%s", recorder.Code, recorder.Header().Get(dataSourceHeader), recorder.Header().Get(dataFreshnessHeader), recorder.Body.String())
+	}
+}
+
+func TestResultsAndGridIdentityFailuresReportPartial(t *testing.T) {
+	tests := []struct {
+		name string
+		path string
+		body string
+		run  func(*Server, http.ResponseWriter, *http.Request)
+	}{
+		{name: "results", path: "/v1/session_result", body: `[{"driver_number":1,"position":1}]`, run: func(s *Server, w http.ResponseWriter, r *http.Request) { s.handleResults(w, r) }},
+		{name: "grid", path: "/v1/starting_grid", body: `[{"driver_number":1,"position":1}]`, run: func(s *Server, w http.ResponseWriter, r *http.Request) { s.handleGrid(w, r) }},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := componentTestServer(t, map[string]string{tt.path: tt.body}, map[string]bool{"/v1/drivers": true})
+			recorder := httptest.NewRecorder()
+			tt.run(server, recorder, httptest.NewRequest(http.MethodGet, "/api/v1/"+tt.name+"?session_key=99&source=openf1", nil))
+			assertAvailabilityHeaders(t, recorder, "openf1", "partial")
+		})
+	}
+}
+
+func TestStrategyOptionalComponentFailureReportsPartial(t *testing.T) {
+	server := componentTestServer(t, map[string]string{
+		"/v1/stints":         `[{"driver_number":1,"stint_number":1,"lap_start":1,"lap_end":10,"compound":"MEDIUM"}]`,
+		"/v1/pit":            `[]`,
+		"/v1/session_result": `[{"driver_number":1,"position":1,"number_of_laps":10}]`,
+		"/v1/race_control":   `[]`,
+	}, map[string]bool{"/v1/drivers": true})
+	recorder := httptest.NewRecorder()
+	server.handleStrategy(recorder, httptest.NewRequest(http.MethodGet, "/api/v1/strategy?session_key=99", nil))
+	assertAvailabilityHeaders(t, recorder, "openf1", "partial")
+}
+
+func TestLapsComparisonDoesNotLabelMissingComponentsFresh(t *testing.T) {
+	tests := []struct {
+		name      string
+		laps      string
+		freshness string
+	}{
+		{name: "empty primary data", laps: `[]`, freshness: "limited"},
+		{name: "optional components failed", laps: `[{"driver_number":1,"lap_number":1}]`, freshness: "partial"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := componentTestServer(t, map[string]string{"/v1/laps": tt.laps}, map[string]bool{
+				"/v1/stints":       true,
+				"/v1/pit":          true,
+				"/v1/race_control": true,
+				"/v1/drivers":      true,
+			})
+			recorder := httptest.NewRecorder()
+			server.handleLapsComparison(recorder, httptest.NewRequest(http.MethodGet, "/api/v1/laps/comparison?session_key=99", nil))
+			assertAvailabilityHeaders(t, recorder, "openf1", tt.freshness)
+		})
+	}
+	t.Run("primary laps failure is an error", func(t *testing.T) {
+		server := componentTestServer(t, nil, map[string]bool{
+			"/v1/laps":         true,
+			"/v1/stints":       true,
+			"/v1/pit":          true,
+			"/v1/race_control": true,
+		})
+		recorder := httptest.NewRecorder()
+		server.handleLapsComparison(recorder, httptest.NewRequest(http.MethodGet, "/api/v1/laps/comparison?session_key=99", nil))
+		if recorder.Code != http.StatusInternalServerError {
+			t.Fatalf("status = %d body=%s", recorder.Code, recorder.Body.String())
+		}
+	})
+}

internal/web/context.go

@@ -9,8 +9,8 @@ import (
 )
 
 func (s *Server) handleWeekendContext(w http.ResponseWriter, _ *http.Request) {
-	markLocalResponse(w, false)
 	if !s.hasLocalQuery() {
+		markDataResponse(w, "none", "limited")
 		writeJSON(w, query.WeekendContext{TemporalState: query.TemporalNoSeason})
 		return
 	}
@@ -30,15 +30,33 @@ func (s *Server) handleWeekendContext(w http.ResponseWriter, _ *http.Request) {
 		writeError(w, err, http.StatusInternalServerError, false)
 		return
 	}
-	for _, ref := range []*query.ContextSession{context.ActiveSession, context.PreviousCompletedSession, context.DefaultAnalysisSession, context.NextSession} {
+	if focus := focusedContextSession(context); focus != nil {
-		if ref != nil && ref.Availability.Freshness != "local" {
+		markDataResponse(w, focus.Availability.Source, focus.Availability.Freshness)
-			markDataResponse(w, ref.Availability.Source, ref.Availability.Freshness)
+	} else {
-			break
+		markDataResponse(w, "none", "limited")
-		}
 	}
 	writeJSON(w, context)
 }
 
+// focusedContextSession selects the session whose state the Weekend shell is
+// presenting. An older terminal/default session must never override an
+// upcoming focus session's metadata.
+func focusedContextSession(context query.WeekendContext) *query.ContextSession {
+	if context.ActiveSession != nil {
+		return context.ActiveSession
+	}
+	if context.FocusMeeting == nil {
+		return nil
+	}
+	focusKey := context.FocusMeeting.MeetingKey
+	for _, ref := range []*query.ContextSession{context.NextSession, context.PreviousCompletedSession, context.DefaultAnalysisSession} {
+		if ref != nil && ref.Meeting != nil && ref.Meeting.MeetingKey == focusKey {
+			return ref
+		}
+	}
+	return nil
+}
+
 func liveEvidence(data *live.LiveStreamData, active, final bool) query.LiveEvidence {
 	return query.LiveEvidence{Active: active, Final: final, MeetingName: data.Session.MeetingName, CircuitName: data.Session.CircuitName, SessionName: data.Session.SessionName, SessionType: data.Session.SessionType}
 }

internal/web/context_test.go

@@ -47,6 +47,19 @@ func TestWeekendContextHandlerWithoutStoreReturnsNoSeason(t *testing.T) {
 	if got.TemporalState != query.TemporalNoSeason {
 		t.Fatalf("state = %s", got.TemporalState)
 	}
+	if rr.Header().Get(dataSourceHeader) != "none" || rr.Header().Get(dataFreshnessHeader) != "limited" {
+		t.Fatalf("missing context metadata = %q/%q", rr.Header().Get(dataSourceHeader), rr.Header().Get(dataFreshnessHeader))
+	}
+}
+
+func TestWeekendContextHandlerEmptyStoreReportsLimited(t *testing.T) {
+	st := openContextStore(t)
+	s := NewServer(nil, 0, st)
+	rr := httptest.NewRecorder()
+	s.handleWeekendContext(rr, httptest.NewRequest(http.MethodGet, "/api/v1/weekend-context", nil))
+	if rr.Code != http.StatusOK || rr.Header().Get(dataSourceHeader) != "none" || rr.Header().Get(dataFreshnessHeader) != "limited" {
+		t.Fatalf("empty context = %d %q/%q body=%s", rr.Code, rr.Header().Get(dataSourceHeader), rr.Header().Get(dataFreshnessHeader), rr.Body.String())
+	}
 }
 
 func TestWeekendContextHandlerUsesLiveHubIdentityWithoutOpenF1(t *testing.T) {
@@ -111,6 +124,37 @@ func TestWeekendContextHandlerUsesTerminalArchiveAsCompletionEvidence(t *testing
 	}
 }
 
+func TestWeekendContextMetadataFollowsUpcomingFocusNotTerminalPrevious(t *testing.T) {
+	st := openContextStore(t)
+	seedContextHandler(t, st)
+	if err := st.UpsertMeeting(store.Meeting{MeetingKey: 2, MeetingName: "Belgian Grand Prix", CircuitShortName: "Spa", Year: 2026, DateStart: "2026-07-10T09:00:00Z", DateEnd: "2026-07-12T16:00:00Z"}); err != nil {
+		t.Fatal(err)
+	}
+	if err := st.UpsertSession(store.Session{SessionKey: 21, MeetingKey: 2, SessionName: "Practice 1", SessionType: "Practice", DateStart: "2026-07-10T09:00:00Z", DateEnd: "2026-07-10T10:00:00Z"}); err != nil {
+		t.Fatal(err)
+	}
+	now, _ := time.Parse(time.RFC3339, "2026-07-05T16:05:00Z")
+	s := NewServer(nil, 0, st)
+	s.query = query.NewServiceWithClock(st, func() time.Time { return now })
+	s.hub.applySnapshot(live.LiveStreamData{SessionStatus: "Finished", Session: live.LiveSessionMeta{MeetingName: "British Grand Prix", CircuitName: "Silverstone", SessionName: "Race", SessionType: "Race"}}, now)
+
+	rr := httptest.NewRecorder()
+	s.handleWeekendContext(rr, httptest.NewRequest(http.MethodGet, "/api/v1/weekend-context", nil))
+	var got query.WeekendContext
+	if err := json.Unmarshal(rr.Body.Bytes(), &got); err != nil {
+		t.Fatal(err)
+	}
+	if got.FocusMeeting == nil || got.FocusMeeting.MeetingKey != 2 || got.NextSession == nil {
+		t.Fatalf("focus context = %+v", got)
+	}
+	if got.PreviousCompletedSession == nil || got.PreviousCompletedSession.Availability.Freshness != "archive" {
+		t.Fatalf("terminal previous missing = %+v", got.PreviousCompletedSession)
+	}
+	if rr.Header().Get(dataSourceHeader) != "local" || rr.Header().Get(dataFreshnessHeader) != "local" {
+		t.Fatalf("focus metadata was overridden by archive = %q/%q", rr.Header().Get(dataSourceHeader), rr.Header().Get(dataFreshnessHeader))
+	}
+}
+
 func TestTerminalSessionStatus(t *testing.T) {
 	for _, status := range []string{"Finished", "Finalised", "ENDED", "Aborted"} {
 		if !terminalSessionStatus(status) {

internal/web/driversummary.go

@@ -1,6 +1,7 @@
 package web
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"strconv"
@@ -89,7 +90,7 @@ func (s *Server) handleDriverSummary(w http.ResponseWriter, r *http.Request) {
 		}
 		if ok {
 			if mode != sourceLocal {
-				tryEnrichDriverSummary(client, &resp, sessionKey)
+				tryEnrichDriverSummary(r.Context(), client, &resp, sessionKey)
 			}
 			switch resp.Enrichment {
 			case "full":
@@ -108,7 +109,7 @@ func (s *Server) handleDriverSummary(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	resp, err := openF1DriverSummary(client, year, driverNumber)
+	resp, incomplete, err := openF1DriverSummary(client, year, driverNumber)
 	if err != nil {
 		writeError(w, err, http.StatusInternalServerError, client.LastResponseWasStale())
 		return
@@ -117,7 +118,7 @@ func (s *Server) handleDriverSummary(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, fmt.Sprintf("driver %d not found in %d championship", driverNumber, year), http.StatusNotFound)
 		return
 	}
-	markOpenF1Response(w, client)
+	markOpenF1AggregateResponse(w, client, incomplete)
 	writeJSON(w, resp)
 }
 
@@ -163,10 +164,10 @@ func (s *Server) localDriverSummary(year, driverNumber int) (driverSummaryRespon
 	return resp, sessionKey, true, nil
 }
 
-func openF1DriverSummary(client *api.OpenF1Client, year, driverNumber int) (*driverSummaryResponse, error) {
+func openF1DriverSummary(client *api.OpenF1Client, year, driverNumber int) (*driverSummaryResponse, bool, error) {
 	champ, err := client.GetDriverChampionshipForYear(year)
 	if err != nil {
-		return nil, err
+		return nil, false, err
 	}
 	var entry *models.ChampionshipDriver
 	for i := range champ {
@@ -176,7 +177,7 @@ func openF1DriverSummary(client *api.OpenF1Client, year, driverNumber int) (*dri
 		}
 	}
 	if entry == nil {
-		return nil, nil
+		return nil, false, nil
 	}
 
 	driverInfo := map[int]models.Driver{}
@@ -184,28 +185,41 @@ func openF1DriverSummary(client *api.OpenF1Client, year, driverNumber int) (*dri
 	if ds, derr := client.GetDriversForSession(sessionKey); derr == nil {
 		driverInfo = buildDriverMapFirst(ds)
 	}
-	if d, ok := championshipDriverInfo(client, entry.SessionKey, driverNumber, driverInfo); ok {
+	d, directErr := client.GetDriver(entry.SessionKey, driverNumber)
-		driverInfo[driverNumber] = d
+	if directErr == nil && d != nil {
+		driverInfo[driverNumber] = *d
+	} else if fallback, ok := driverInfo[driverNumber]; ok {
+		driverInfo[driverNumber] = fallback
 	}
-
+	identityIncomplete := !hasDriverPresentation(driverInfo[driverNumber])
-	races, _, err := fetchSeasonRaces(client, year)
+	races, racesIncomplete, err := fetchSeasonRaces(client, year)
 	if err != nil {
-		return nil, err
+		return nil, false, err
 	}
 
 	resp, ok := aggregateDriverSummary(year, driverNumber, races, champ, driverInfo)
 	if !ok {
-		return nil, nil
+		return nil, false, nil
 	}
+	incomplete := identityIncomplete || racesIncomplete
 	resp.Source = "openf1"
-	resp.Enrichment = "full"
+	if identityIncomplete {
-	return &resp, nil
+		resp.Enrichment = "limited"
+	} else {
+		resp.Enrichment = "full"
+	}
+	return &resp, incomplete, nil
+}
+
+func hasDriverPresentation(driver models.Driver) bool {
+	hasName := driver.FullName != "" || driver.NameAcronym != "" || driver.BroadcastName != ""
+	return hasName && driver.TeamName != "" && driver.TeamColour != ""
 }
 
 // tryEnrichDriverSummary optionally fills headshot / polished identity from
 // OpenF1. It never blocks longer than driverEnrichmentTimeout — on timeout or
 // failure the local profile remains intact with enrichment=limited.
-func tryEnrichDriverSummary(client *api.OpenF1Client, resp *driverSummaryResponse, sessionKey int) {
+func tryEnrichDriverSummary(parent context.Context, client *api.OpenF1Client, resp *driverSummaryResponse, sessionKey int) {
 	if resp == nil || client == nil || sessionKey <= 0 {
 		if resp != nil && resp.Enrichment == "none" {
 			// No session to enrich from — leave as none (local identity only).
@@ -213,28 +227,15 @@ func tryEnrichDriverSummary(client *api.OpenF1Client, resp *driverSummaryRespons
 		return
 	}
 
-	type enrichResult struct {
+	ctx, cancel := context.WithTimeout(parent, driverEnrichmentTimeout)
-		driver models.Driver
+	defer cancel()
-		ok     bool
+	driver, err := client.GetDriverContext(ctx, sessionKey, resp.DriverNumber)
-	}
+	if err != nil || driver == nil {
-
-	done := make(chan enrichResult, 1)
-	go func() {
-		d, ok := championshipDriverInfo(client, sessionKey, resp.DriverNumber, nil)
-		done <- enrichResult{driver: d, ok: ok}
-	}()
-
-	select {
-	case result := <-done:
-		if !result.ok {
-			resp.Enrichment = "limited"
-			return
-		}
-		applyDriverEnrichment(resp, result.driver)
-		resp.Enrichment = "full"
-	case <-time.After(driverEnrichmentTimeout):
 		resp.Enrichment = "limited"
+		return
 	}
+	applyDriverEnrichment(resp, *driver)
+	resp.Enrichment = "full"
 }
 
 func applyDriverEnrichment(resp *driverSummaryResponse, d models.Driver) {

internal/web/driversummary_test.go

@@ -2,6 +2,7 @@ package web
 
 import (
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -212,10 +213,12 @@ func TestHandleDriverSummaryLocalFirstIgnoresHangingEnrichment(t *testing.T) {
 
 	// Enrichment seam: OpenF1 hangs until released. Local summary must still return.
 	release := make(chan struct{})
+	cancelObserved := make(chan struct{})
 	hang := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		select {
 		case <-release:
 		case <-r.Context().Done():
+			close(cancelObserved)
 		}
 	}))
 	t.Cleanup(func() {
@@ -239,6 +242,11 @@ func TestHandleDriverSummaryLocalFirstIgnoresHangingEnrichment(t *testing.T) {
 	if elapsed > 500*time.Millisecond {
 		t.Fatalf("handler blocked on enrichment for %v", elapsed)
 	}
+	select {
+	case <-cancelObserved:
+	case <-time.After(250 * time.Millisecond):
+		t.Fatal("timed-out enrichment did not cancel its upstream request")
+	}
 
 	var resp driverSummaryResponse
 	if err := json.NewDecoder(rec.Body).Decode(&resp); err != nil {
@@ -323,3 +331,42 @@ func TestHandleDriverSummarySourceLocalOnly(t *testing.T) {
 		t.Fatalf("local metadata = %q/%q", rec.Header().Get(dataSourceHeader), rec.Header().Get(dataFreshnessHeader))
 	}
 }
+
+func TestHandleRemoteDriverSummaryReportsIdentityAndRoundLimitations(t *testing.T) {
+	tests := []struct {
+		name           string
+		driversOK      bool
+		meetingHasRace bool
+		wantEnrichment string
+	}{
+		{name: "missing identity", driversOK: false, meetingHasRace: true, wantEnrichment: "limited"},
+		{name: "missing race round", driversOK: true, meetingHasRace: false, wantEnrichment: "full"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			upstream := championshipTestUpstream(t, tt.driversOK, tt.meetingHasRace)
+			defer upstream.Close()
+			client := api.NewOpenF1Client(upstream.URL, 2*time.Second)
+			defer client.Close()
+			server := NewServer(client, 0, nil)
+			year := time.Now().Year()
+			recorder := httptest.NewRecorder()
+			request := httptest.NewRequest(http.MethodGet, fmt.Sprintf("/api/v1/driver/summary?year=%d&driver_number=1&source=openf1", year), nil)
+
+			server.handleDriverSummary(recorder, request)
+			if recorder.Code != http.StatusOK {
+				t.Fatalf("status = %d body=%s", recorder.Code, recorder.Body.String())
+			}
+			var response driverSummaryResponse
+			if err := json.Unmarshal(recorder.Body.Bytes(), &response); err != nil {
+				t.Fatal(err)
+			}
+			if response.Enrichment != tt.wantEnrichment {
+				t.Fatalf("enrichment = %q, want %q", response.Enrichment, tt.wantEnrichment)
+			}
+			if recorder.Header().Get(dataSourceHeader) != "openf1" || recorder.Header().Get(dataFreshnessHeader) != "partial" {
+				t.Fatalf("remote limitation metadata = %q/%q", recorder.Header().Get(dataSourceHeader), recorder.Header().Get(dataFreshnessHeader))
+			}
+		})
+	}
+}

internal/web/freshness.go

@@ -18,16 +18,23 @@ func markOpenF1Response(w http.ResponseWriter, client *api.OpenF1Client) {
 }
 
 func markOpenF1AggregateResponse(w http.ResponseWriter, client *api.OpenF1Client, partial bool) {
+	freshness := "fresh"
+	if partial {
+		freshness = "partial"
+	}
+	markOpenF1Availability(w, client, freshness)
+}
+
+func markOpenF1Availability(w http.ResponseWriter, client *api.OpenF1Client, freshness string) {
 	w.Header().Set(dataSourceHeader, "openf1")
 	if client != nil && client.LastResponseWasStale() {
 		w.Header().Set(dataFreshnessHeader, "stale")
 		return
 	}
-	if partial {
+	if freshness == "" {
-		w.Header().Set(dataFreshnessHeader, "partial")
+		freshness = "fresh"
-		return
 	}
-	w.Header().Set(dataFreshnessHeader, "fresh")
+	w.Header().Set(dataFreshnessHeader, freshness)
 }
 
 func markDataResponse(w http.ResponseWriter, source, freshness string) {

internal/web/racehub.go

@@ -17,7 +17,7 @@ func (s *Server) handleRaceHub(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if !s.hasLocalQuery() {
-		markDataResponse(w, "local", "limited")
+		markDataResponse(w, "none", "limited")
 		writeJSON(w, emptyRaceHub(sessionKey))
 		return
 	}
@@ -27,7 +27,14 @@ func (s *Server) handleRaceHub(w http.ResponseWriter, r *http.Request) {
 		writeError(w, err, http.StatusInternalServerError, false)
 		return
 	}
-	markLocalResponse(w, hub.Source == query.ResponseSourcePartial)
+	switch hub.Source {
+	case query.ResponseSourceNone:
+		markDataResponse(w, "none", "limited")
+	case query.ResponseSourcePartial:
+		markLocalResponse(w, true)
+	default:
+		markLocalResponse(w, false)
+	}
 	writeJSON(w, hub)
 }
 

internal/web/racehub_test.go

@@ -86,7 +86,7 @@ func TestHandleRaceHubWithoutStore(t *testing.T) {
 	if hub.Source != query.ResponseSourceNone {
 		t.Fatalf("source = %q, want %q", hub.Source, query.ResponseSourceNone)
 	}
-	if rec.Header().Get(dataSourceHeader) != "local" || rec.Header().Get(dataFreshnessHeader) != "limited" {
+	if rec.Header().Get(dataSourceHeader) != "none" || rec.Header().Get(dataFreshnessHeader) != "limited" {
 		t.Fatalf("missing hub metadata = %q/%q", rec.Header().Get(dataSourceHeader), rec.Header().Get(dataFreshnessHeader))
 	}
 	if hub.Datasets["session"].Status != query.DatasetStatusMissing {
@@ -94,6 +94,21 @@ func TestHandleRaceHubWithoutStore(t *testing.T) {
 	}
 }
 
+func TestHandleRaceHubUnknownSessionWithStoreReportsLimited(t *testing.T) {
+	st := openTestStore(t)
+	srv := testServer(t, st)
+	rec := httptest.NewRecorder()
+	srv.handleRaceHub(rec, httptest.NewRequest(http.MethodGet, "/api/v1/race-hub?session_key=999999", nil))
+
+	var hub query.RaceHub
+	if err := json.Unmarshal(rec.Body.Bytes(), &hub); err != nil {
+		t.Fatal(err)
+	}
+	if hub.Source != query.ResponseSourceNone || rec.Header().Get(dataSourceHeader) != "none" || rec.Header().Get(dataFreshnessHeader) != "limited" {
+		t.Fatalf("unknown session = source %q, metadata %q/%q", hub.Source, rec.Header().Get(dataSourceHeader), rec.Header().Get(dataFreshnessHeader))
+	}
+}
+
 func TestHandleRaceHubWithLocalData(t *testing.T) {
 	st := openTestStore(t)
 	seedRaceHubStore(t, st)

internal/web/replay.go

@@ -62,16 +62,26 @@ func (s *Server) handleReplayFrames(w http.ResponseWriter, r *http.Request) {
 	}
 
 	client := s.client.Scoped()
-	resp, err := assembleReplayFrames(r.Context(), client, sessionKey, intervalMS)
+	resp, incomplete, err := assembleReplayFrames(r.Context(), client, sessionKey, intervalMS)
 	if err != nil {
 		writeError(w, err, http.StatusInternalServerError, client.LastResponseWasStale())
 		return
 	}
-	markOpenF1Response(w, client)
+	markOpenF1Availability(w, client, replayResponseFreshness(resp, incomplete))
 	writeJSON(w, resp)
 }
 
-func assembleReplayFrames(ctx context.Context, client replayDataClient, sessionKey, intervalMS int) (replayFramesResponse, error) {
+func replayResponseFreshness(resp replayFramesResponse, incomplete bool) string {
+	if !incomplete {
+		return "fresh"
+	}
+	if len(resp.Frames) == 0 {
+		return "limited"
+	}
+	return "partial"
+}
+
+func assembleReplayFrames(ctx context.Context, client replayDataClient, sessionKey, intervalMS int) (replayFramesResponse, bool, error) {
 	if intervalMS < defaultReplayIntervalMS {
 		intervalMS = defaultReplayIntervalMS
 	}
@@ -84,26 +94,26 @@ func assembleReplayFrames(ctx context.Context, client replayDataClient, sessionK
 
 	drivers, err := client.GetDriversForSession(sessionKey)
 	if err != nil {
-		return resp, err
+		return resp, false, err
 	}
 
 	driverNumbers := uniqueDriverNumbers(drivers)
 	if len(driverNumbers) == 0 {
-		return resp, nil
+		return resp, true, nil
 	}
 
 	series, err := fetchReplayLocationSeries(ctx, client, sessionKey, driverNumbers)
 	if err != nil && len(series) == 0 {
-		return resp, err
+		return resp, false, err
 	}
 
 	start, ok := earliestReplayLocationTime(series)
 	if !ok {
-		return resp, nil
+		return resp, true, nil
 	}
 	resp.StartTime = start.Format(time.RFC3339Nano)
 	resp.Frames = snapReplayFrames(series, start, intervalMS)
-	return resp, nil
+	return resp, err != nil || len(resp.Frames) == 0, nil
 }
 
 func uniqueDriverNumbers(drivers []models.Driver) []int {

internal/web/replay_test.go

@@ -3,6 +3,7 @@ package web
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"net/http"
 	"net/http/httptest"
 	"sync"
@@ -16,6 +17,7 @@ type fakeReplayClient struct {
 	drivers []models.Driver
 	locs    map[int][]models.Location
 	err     error
+	locErrs map[int]error
 
 	mu          sync.Mutex
 	inFlight    int
@@ -46,7 +48,38 @@ func (f *fakeReplayClient) GetLocation(sessionKey, driverNumber int) ([]models.L
 	f.inFlight--
 	f.mu.Unlock()
 
-	return f.locs[driverNumber], nil
+	return f.locs[driverNumber], f.locErrs[driverNumber]
+}
+
+func TestAssembleReplayFramesReportsPartialDriverSeries(t *testing.T) {
+	start := time.Date(2025, 5, 25, 13, 0, 0, 0, time.UTC)
+	client := &fakeReplayClient{
+		drivers: []models.Driver{{DriverNumber: 1}, {DriverNumber: 4}},
+		locs: map[int][]models.Location{
+			1: {{Date: start.Format(time.RFC3339Nano), X: 1, Y: 2}},
+		},
+		locErrs: map[int]error{4: errors.New("location unavailable")},
+	}
+	resp, incomplete, err := assembleReplayFrames(context.Background(), client, 99, defaultReplayIntervalMS)
+	if err != nil {
+		t.Fatalf("partial replay should remain usable: %v", err)
+	}
+	if !incomplete || len(resp.Frames) != 1 {
+		t.Fatalf("partial replay = incomplete %v, frames %+v", incomplete, resp.Frames)
+	}
+	if got := replayResponseFreshness(resp, incomplete); got != "partial" {
+		t.Fatalf("partial replay freshness = %q", got)
+	}
+}
+
+func TestAssembleReplayFramesEmptyDriverSetIsLimited(t *testing.T) {
+	resp, incomplete, err := assembleReplayFrames(context.Background(), &fakeReplayClient{}, 99, defaultReplayIntervalMS)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !incomplete || replayResponseFreshness(resp, incomplete) != "limited" {
+		t.Fatalf("empty replay = incomplete %v, freshness %q", incomplete, replayResponseFreshness(resp, incomplete))
+	}
 }
 
 func TestAssembleReplayFramesSnapsNearestSamplesAndOmitsEmptyDrivers(t *testing.T) {
@@ -70,10 +103,13 @@ func TestAssembleReplayFramesSnapsNearestSamplesAndOmitsEmptyDrivers(t *testing.
 		},
 	}
 
-	resp, err := assembleReplayFrames(context.Background(), client, 99, 5000)
+	resp, incomplete, err := assembleReplayFrames(context.Background(), client, 99, 5000)
 	if err != nil {
 		t.Fatalf("assembleReplayFrames() error = %v", err)
 	}
+	if incomplete {
+		t.Fatal("complete driver series reported incomplete")
+	}
 	if resp.SessionKey != 99 || resp.Interval != 5000 {
 		t.Fatalf("response metadata = %+v", resp)
 	}
@@ -112,7 +148,7 @@ func TestAssembleReplayFramesCapsFrameCount(t *testing.T) {
 		locs:    map[int][]models.Location{1: locs},
 	}
 
-	resp, err := assembleReplayFrames(context.Background(), client, 99, defaultReplayIntervalMS)
+	resp, _, err := assembleReplayFrames(context.Background(), client, 99, defaultReplayIntervalMS)
 	if err != nil {
 		t.Fatalf("assembleReplayFrames() error = %v", err)
 	}
@@ -139,7 +175,7 @@ func TestAssembleReplayFramesBoundsLocationFanOut(t *testing.T) {
 		delay:   5 * time.Millisecond,
 	}
 
-	if _, err := assembleReplayFrames(context.Background(), client, 99, defaultReplayIntervalMS); err != nil {
+	if _, _, err := assembleReplayFrames(context.Background(), client, 99, defaultReplayIntervalMS); err != nil {
 		t.Fatalf("assembleReplayFrames() error = %v", err)
 	}
 	if client.maxInFlight > replayFetchConcurrency {
@@ -167,7 +203,7 @@ func TestHandleReplayFramesValidatesParamsAndFloorsInterval(t *testing.T) {
 	client := &fakeReplayClient{drivers: []models.Driver{{DriverNumber: 1}}, locs: map[int][]models.Location{
 		1: {{Date: time.Date(2025, 5, 25, 13, 0, 0, 0, time.UTC).Format(time.RFC3339Nano), X: 1, Y: 2}},
 	}}
-	resp, err := assembleReplayFrames(context.Background(), client, 99, 1000)
+	resp, _, err := assembleReplayFrames(context.Background(), client, 99, 1000)
 	if err != nil {
 		t.Fatalf("assembleReplayFrames() error = %v", err)
 	}