Feature 04 task 3 (rebased): Household settings seeding and API (#27)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>
Co-committed-by: dev_agent <dev_agent@cubecraftlabs.com>

internal/server/csrf_test.go

@@ -34,9 +34,10 @@ func TestCSRFThroughRouter(t *testing.T) {
 		{"PATCH without header", http.MethodPatch, "/api/v1/settings/household", nil, http.StatusForbidden, csrfJSON},
 		{"DELETE with wrong header", http.MethodDelete, "/api/v1/me", []string{"wrong-token"}, http.StatusForbidden, csrfJSON},
 		// The right token passes the check and reaches the router, which has
-		// no POST /api/v1/me.
+		// no POST /api/v1/me, and the settings handler, which refuses the
+		// empty body.
 		{"POST with right header", http.MethodPost, "/api/v1/me", []string{testSession.CSRFToken}, http.StatusMethodNotAllowed, methodNotAllowedJSON},
-		{"PATCH with right header", http.MethodPatch, "/api/v1/settings/household", []string{testSession.CSRFToken}, http.StatusNotFound, notFoundJSON},
+		{"PATCH with right header", http.MethodPatch, "/api/v1/settings/household", []string{testSession.CSRFToken}, http.StatusBadRequest, `{"error":{"code":"invalid_request","message":"request body must be a JSON object","retryable":false}}`},
 		{"GET without header", http.MethodGet, "/api/v1/me", nil, http.StatusOK, ""},
 		// Only GET is exempt; HEAD and OPTIONS need the header too.
 		{"HEAD without header", http.MethodHead, "/api/v1/me", nil, http.StatusForbidden, csrfJSON},

internal/server/login_test.go

@@ -82,7 +82,7 @@ func newLoginRouter(t *testing.T, issuer string) http.Handler {
 	if err != nil {
 		t.Fatal(err)
 	}
-	r, err := NewRouter(logger, "dev", trusted, flow, sessions,
+	r, err := NewRouter(logger, "dev", trusted, flow, sessions, newTestSettings(t),
 		fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)

internal/server/origin_test.go

@@ -44,7 +44,7 @@ func newOriginRouter(t *testing.T, logs io.Writer) http.Handler {
 		t.Fatal(err)
 	}
 	logger := slog.New(forwarded.LogHandler(slog.NewJSONHandler(logs, nil)))
-	r, err := NewRouter(logger, "dev", trusted, probeAuth{}, stubSessions{},
+	r, err := NewRouter(logger, "dev", trusted, probeAuth{}, stubSessions{}, newTestSettings(t),
 		fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)

internal/server/server.go

@@ -3,6 +3,7 @@ package server
 
 import (
 	"encoding/json"
+	"errors"
 	"io/fs"
 	"log/slog"
 	"net/http"
@@ -11,6 +12,7 @@ import (
 
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/forwarded"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/frontend"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
 )
 
 // reservedPrefixes are owned by the API router and are never answered with the
@@ -26,9 +28,13 @@ type RouteMounter interface {
 // has its client address and scheme resolved, honouring forwarded headers
 // only from a peer in trusted (see resolveOrigin). version is reported by
 // GET /health; auth mounts the /auth routes; sessions guards /api/v1 and
-// /media; assets is the web build served for every other GET. /health, /auth
-// and the web build are public. Requests to /api/v1 other than GET also need the session's CSRF token in CSRFHeader.
-func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, auth RouteMounter, sessions SessionLookup, assets fs.FS) (http.Handler, error) {
+// /media; settings serves /api/v1/settings/household; assets is the web build
+// served for every other GET. /health, /auth and the web build are public.
+// Requests to /api/v1 other than GET also need the session's CSRF token in CSRFHeader.
+func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, auth RouteMounter, sessions SessionLookup, settings *household.SettingsService, assets fs.FS) (http.Handler, error) {
+	if settings == nil {
+		return nil, errors.New("server: nil household settings service")
+	}
 	notFound := apiErrorHandler(logger, http.StatusNotFound, "not_found", "not found")
 	methodNotAllowed := apiErrorHandler(logger, http.StatusMethodNotAllowed, "method_not_allowed", "method not allowed")
 
@@ -55,6 +61,8 @@ func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, a
 		sub.NotFound(notFound)
 	}
 	apiV1.Get("/me", me(logger))
+	apiV1.Get("/settings/household", getHouseholdSettings(logger, settings))
+	apiV1.Patch("/settings/household", patchHouseholdSettings(logger, settings))
 	r.Route("/api", func(r chi.Router) {
 		r.MethodNotAllowed(methodNotAllowed)
 		r.NotFound(notFound)
@@ -80,19 +88,8 @@ type apiError struct {
 
 // apiErrorHandler responds with status and a fixed, non-retryable API error.
 func apiErrorHandler(logger *slog.Logger, status int, code, message string) http.HandlerFunc {
-	body, err := json.Marshal(errorBody{Error: apiError{
-		Code:    code,
-		Message: message,
-	}})
-	if err != nil {
-		panic(err) // fixed string and bool fields cannot fail to marshal
-	}
 	return func(w http.ResponseWriter, r *http.Request) {
-		w.Header().Set("Content-Type", "application/json")
-		w.WriteHeader(status)
-		if _, err := w.Write(body); err != nil {
-			logger.WarnContext(r.Context(), "write error response", "code", code, "error", err)
-		}
+		writeError(w, r, logger, status, code, message)
 	}
 }
 

internal/server/server_test.go

@@ -1,6 +1,7 @@
 package server
 
 import (
+	"context"
 	"encoding/json"
 	"io"
 	"log/slog"
@@ -12,6 +13,10 @@ import (
 	"testing/fstest"
 
 	"github.com/go-chi/chi/v5"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/migrations"
 )
 
 const (
@@ -21,13 +26,18 @@ const (
 )
 
 func newTestRouter(t *testing.T, version string) http.Handler {
+	t.Helper()
+	return newTestRouterWith(t, version, newTestSettings(t))
+}
+
+func newTestRouterWith(t *testing.T, version string, settings *household.SettingsService) http.Handler {
 	t.Helper()
 	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
 	assets := fstest.MapFS{
 		"index.html":             {Data: []byte(fixtureIndex)},
 		"assets/index-AbC123.js": {Data: []byte(fixtureAsset)},
 	}
-	r, err := NewRouter(logger, version, nil, stubAuth{}, stubSessions{}, assets)
+	r, err := NewRouter(logger, version, nil, stubAuth{}, stubSessions{}, settings, assets)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -60,6 +70,38 @@ func TestAuthRoutesMounted(t *testing.T) {
 	}
 }
 
+// newTestSettings returns a settings service over a migrated temp database
+// seeded with zone America/New_York.
+func newTestSettings(t *testing.T) *household.SettingsService {
+	t.Helper()
+	ctx := context.Background()
+	st, err := store.Open(ctx, t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		if err := st.Close(); err != nil {
+			t.Error(err)
+		}
+	})
+	if err := store.Migrate(ctx, st.Writer, migrations.FS); err != nil {
+		t.Fatal(err)
+	}
+	if err := household.SeedSettings(ctx, st, "America/New_York"); err != nil {
+		t.Fatal(err)
+	}
+	return household.NewSettingsService(st)
+}
+
+func TestNewRouterRequiresSettings(t *testing.T) {
+	t.Parallel()
+
+	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
+	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, nil, fstest.MapFS{"index.html": {}}); err == nil {
+		t.Fatal("NewRouter accepted a nil settings service")
+	}
+}
+
 func TestHealth(t *testing.T) {
 	t.Parallel()
 

internal/server/settings.go

@@ -0,0 +1,135 @@
+package server
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/http"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/auth"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+)
+
+// maxSettingsBody bounds a PATCH /settings/household request body.
+const maxSettingsBody = 16 << 10
+
+// settingsPatch is the PATCH /settings/household body. Every field is
+// optional; unknown fields and null values are refused.
+type settingsPatch struct {
+	Timezone         *string `json:"timezone"`
+	DinnerTime       *string `json:"dinner_time"`
+	ReminderTime     *string `json:"reminder_time"`
+	ReviewTime       *string `json:"review_time"`
+	PlanDraftDow     *int    `json:"plan_draft_dow"`
+	PlanDraftTime    *string `json:"plan_draft_time"`
+	SuggestionsDow   *int    `json:"suggestions_dow"`
+	SuggestionsTime  *string `json:"suggestions_time"`
+	ChatAutosendDow  *int    `json:"chat_autosend_dow"`
+	ChatAutosendTime *string `json:"chat_autosend_time"`
+}
+
+func getHouseholdSettings(logger *slog.Logger, svc *household.SettingsService) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		settings, err := svc.Get(r.Context())
+		if err != nil {
+			logger.ErrorContext(r.Context(), "get household settings", "error", err)
+			writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+			return
+		}
+		writeJSON(w, r, logger, http.StatusOK, settings)
+	}
+}
+
+// patchHouseholdSettings records the session's actor subject as updated_by.
+func patchHouseholdSettings(logger *slog.Logger, svc *household.SettingsService) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		actor, ok := auth.ActorFrom(r.Context())
+		if !ok {
+			logger.ErrorContext(r.Context(), "PATCH /api/v1/settings/household without a session")
+			writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+			return
+		}
+		patch, err := decodeSettingsPatch(http.MaxBytesReader(w, r.Body, maxSettingsBody))
+		if err != nil {
+			writeError(w, r, logger, http.StatusBadRequest, "invalid_request", err.Error())
+			return
+		}
+		settings, err := svc.Update(r.Context(), household.SettingsPatch(patch), actor.Subject)
+		var invalid *household.ValidationError
+		if errors.As(err, &invalid) {
+			writeError(w, r, logger, http.StatusBadRequest, "invalid_settings", invalid.Error())
+			return
+		}
+		if err != nil {
+			logger.ErrorContext(r.Context(), "update household settings", "error", err)
+			writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+			return
+		}
+		writeJSON(w, r, logger, http.StatusOK, settings)
+	}
+}
+
+// decodeSettingsPatch reads a single JSON object, refusing unknown fields,
+// null values and trailing data.
+func decodeSettingsPatch(body io.Reader) (settingsPatch, error) {
+	data, err := io.ReadAll(body)
+	if err != nil {
+		var tooLarge *http.MaxBytesError
+		if errors.As(err, &tooLarge) {
+			return settingsPatch{}, fmt.Errorf("request body exceeds %d bytes", tooLarge.Limit)
+		}
+		return settingsPatch{}, errors.New("cannot read request body")
+	}
+
+	var fields map[string]json.RawMessage
+	if err := json.Unmarshal(data, &fields); err != nil || fields == nil {
+		return settingsPatch{}, errors.New("request body must be a JSON object")
+	}
+	for name, raw := range fields {
+		if bytes.Equal(raw, []byte("null")) {
+			return settingsPatch{}, fmt.Errorf("%s: must not be null", name)
+		}
+	}
+
+	var patch settingsPatch
+	dec := json.NewDecoder(bytes.NewReader(data))
+	dec.DisallowUnknownFields()
+	if err := dec.Decode(&patch); err != nil {
+		var typeErr *json.UnmarshalTypeError
+		if errors.As(err, &typeErr) {
+			return settingsPatch{}, fmt.Errorf("%s: want a JSON %s", typeErr.Field, typeErr.Type)
+		}
+		return settingsPatch{}, fmt.Errorf("invalid settings: %v", err)
+	}
+	return patch, nil
+}
+
+func writeJSON(w http.ResponseWriter, r *http.Request, logger *slog.Logger, status int, v any) {
+	body, err := json.Marshal(v)
+	if err != nil {
+		logger.ErrorContext(r.Context(), "encode response", "error", err)
+		writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+		return
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	if _, err := w.Write(body); err != nil {
+		logger.WarnContext(r.Context(), "write response", "error", err)
+	}
+}
+
+// writeError responds with status and a non-retryable API error.
+func writeError(w http.ResponseWriter, r *http.Request, logger *slog.Logger, status int, code, message string) {
+	body, err := json.Marshal(errorBody{Error: apiError{Code: code, Message: message}})
+	if err != nil {
+		panic(err) // string and bool fields cannot fail to marshal
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	if _, err := w.Write(body); err != nil {
+		logger.WarnContext(r.Context(), "write error response", "code", code, "error", err)
+	}
+}

internal/server/settings_test.go

@@ -0,0 +1,278 @@
+package server
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"testing/fstest"
+	"time"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/auth"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/migrations"
+)
+
+const settingsPath = "/api/v1/settings/household"
+
+// signedIn returns a request carrying stubSessions' valid session cookie and
+// its CSRF token.
+func signedIn(method, target string, body io.Reader) *http.Request {
+	req := httptest.NewRequest(method, target, body)
+	req.AddCookie(validSessionCookie)
+	req.Header.Set(CSRFHeader, testSession.CSRFToken)
+	return req
+}
+
+func serve(t *testing.T, h http.Handler, req *http.Request) (*httptest.ResponseRecorder, map[string]any) {
+	t.Helper()
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, req)
+	if ct := rec.Header().Get("Content-Type"); ct != "application/json" {
+		t.Errorf("Content-Type = %q, want application/json", ct)
+	}
+	var body map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("decode body %q: %v", rec.Body.String(), err)
+	}
+	return rec, body
+}
+
+func TestGetHouseholdSettings(t *testing.T) {
+	t.Parallel()
+
+	rec, body := serve(t, newTestRouter(t, "dev"), signedIn(http.MethodGet, settingsPath, nil))
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d, want 200: %s", rec.Code, rec.Body)
+	}
+	want := map[string]any{
+		"timezone":                "America/New_York",
+		"dinner_time":             "17:30",
+		"reminder_time":           "16:30",
+		"review_time":             "09:00",
+		"plan_draft_dow":          float64(5),
+		"plan_draft_time":         "09:00",
+		"suggestions_dow":         float64(0),
+		"suggestions_time":        "08:00",
+		"chat_autosend_dow":       float64(6),
+		"chat_autosend_time":      "08:00",
+		"onboarding_completed_at": nil,
+		"updates_seen_at":         nil,
+		"updated_by":              nil,
+	}
+	for k, v := range want {
+		got, ok := body[k]
+		if !ok || got != v {
+			t.Errorf("%s = %#v (present %v), want %#v", k, got, ok, v)
+		}
+	}
+	for _, k := range []string{"created_at", "updated_at"} {
+		if s, ok := body[k].(string); !ok || s == "" {
+			t.Errorf("%s = %#v, want a timestamp", k, body[k])
+		}
+	}
+	if len(body) != len(want)+2 {
+		t.Errorf("body has %d fields, want %d: %v", len(body), len(want)+2, body)
+	}
+}
+
+func TestPatchHouseholdSettings(t *testing.T) {
+	t.Parallel()
+	settings := newTestSettings(t)
+	router := newTestRouterWith(t, "dev", settings)
+
+	var notified []household.Settings
+	settings.Subscribe(func(s household.Settings) { notified = append(notified, s) })
+
+	rec, body := serve(t, router, signedIn(http.MethodPatch, settingsPath,
+		strings.NewReader(`{"timezone":"Europe/Berlin","dinner_time":"18:00","plan_draft_dow":4}`)))
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d, want 200: %s", rec.Code, rec.Body)
+	}
+	for k, v := range map[string]any{
+		"timezone":       "Europe/Berlin",
+		"dinner_time":    "18:00",
+		"plan_draft_dow": float64(4),
+		"reminder_time":  "16:30", // unchanged
+		"updated_by":     testSession.Subject,
+	} {
+		if body[k] != v {
+			t.Errorf("%s = %#v, want %#v", k, body[k], v)
+		}
+	}
+	if len(notified) != 1 || notified[0].Timezone != "Europe/Berlin" {
+		t.Errorf("subscriber notified with %+v, want one change to Europe/Berlin", notified)
+	}
+
+	_, body = serve(t, router, signedIn(http.MethodGet, settingsPath, nil))
+	if body["timezone"] != "Europe/Berlin" || body["updated_by"] != testSession.Subject {
+		t.Errorf("GET after PATCH = %v", body)
+	}
+}
+
+func TestPatchHouseholdSettingsRejected(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name string
+		body string
+		code string
+		in   string // the error message must contain this
+	}{
+		{"bad timezone", `{"timezone":"Mars/Olympus_Mons"}`, "invalid_settings", "timezone"},
+		{"bad time", `{"dinner_time":"25:00"}`, "invalid_settings", "dinner_time"},
+		{"unpadded time", `{"reminder_time":"9:30"}`, "invalid_settings", "reminder_time"},
+		{"bad dow", `{"suggestions_dow":7}`, "invalid_settings", "suggestions_dow"},
+		{"negative dow", `{"chat_autosend_dow":-1}`, "invalid_settings", "chat_autosend_dow"},
+		{"empty object", `{}`, "invalid_settings", "no settings to change"},
+		{"fractional dow", `{"plan_draft_dow":5.5}`, "invalid_request", "plan_draft_dow"},
+		{"string dow", `{"plan_draft_dow":"5"}`, "invalid_request", "plan_draft_dow"},
+		{"numeric time", `{"dinner_time":1730}`, "invalid_request", "dinner_time"},
+		{"null value", `{"timezone":null}`, "invalid_request", "timezone"},
+		{"unknown field", `{"dinner":"17:30"}`, "invalid_request", "dinner"},
+		{"read-only field", `{"updated_by":"someone"}`, "invalid_request", "updated_by"},
+		{"not an object", `["timezone"]`, "invalid_request", "JSON object"},
+		{"null body", `null`, "invalid_request", "JSON object"},
+		{"trailing data", `{"dinner_time":"18:00"} {}`, "invalid_request", "JSON object"},
+		{"malformed", `{"dinner_time":`, "invalid_request", "JSON object"},
+		{"too large", `{"timezone":"` + strings.Repeat("a", maxSettingsBody) + `"}`, "invalid_request", "exceeds"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			settings := newTestSettings(t)
+			router := newTestRouterWith(t, "dev", settings)
+			notified := 0
+			settings.Subscribe(func(household.Settings) { notified++ })
+
+			rec, body := serve(t, router, signedIn(http.MethodPatch, settingsPath, strings.NewReader(tt.body)))
+			if rec.Code != http.StatusBadRequest {
+				t.Fatalf("status = %d, want 400: %s", rec.Code, rec.Body)
+			}
+			apiErr, ok := body["error"].(map[string]any)
+			if !ok || len(body) != 1 || len(apiErr) != 3 {
+				t.Fatalf("body = %s, want {\"error\":{code,message,retryable}}", rec.Body)
+			}
+			if apiErr["code"] != tt.code || apiErr["retryable"] != false {
+				t.Errorf("error = %v, want code %q, retryable false", apiErr, tt.code)
+			}
+			if msg, _ := apiErr["message"].(string); !strings.Contains(msg, tt.in) {
+				t.Errorf("message %q does not contain %q", msg, tt.in)
+			}
+			if notified != 0 {
+				t.Errorf("rejected PATCH notified subscribers %d times", notified)
+			}
+			_, after := serve(t, router, signedIn(http.MethodGet, settingsPath, nil))
+			if after["timezone"] != "America/New_York" || after["dinner_time"] != "17:30" || after["updated_by"] != nil {
+				t.Errorf("rejected PATCH changed settings: %v", after)
+			}
+		})
+	}
+}
+
+func TestHouseholdSettingsMethodNotAllowed(t *testing.T) {
+	t.Parallel()
+
+	rec, body := serve(t, newTestRouter(t, "dev"), signedIn(http.MethodPut, settingsPath, strings.NewReader(`{}`)))
+	if rec.Code != http.StatusMethodNotAllowed {
+		t.Errorf("status = %d, want 405", rec.Code)
+	}
+	if apiErr, _ := body["error"].(map[string]any); apiErr["code"] != "method_not_allowed" {
+		t.Errorf("body = %v", body)
+	}
+}
+
+// TestHouseholdSettingsWithRealSession drives the settings API through the
+// production router and session manager: a member signs in, reads the CSRF
+// token from GET /api/v1/me and PATCHes; updated_by comes from the session.
+// Without a session, or without the CSRF token, the PATCH is refused and
+// nothing changes.
+func TestHouseholdSettingsWithRealSession(t *testing.T) {
+	t.Parallel()
+	ctx := context.Background()
+	st, err := store.Open(ctx, t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		if err := st.Close(); err != nil {
+			t.Error(err)
+		}
+	})
+	if err := store.Migrate(ctx, st.Writer, migrations.FS); err != nil {
+		t.Fatal(err)
+	}
+	if err := household.SeedSettings(ctx, st, "America/New_York"); err != nil {
+		t.Fatal(err)
+	}
+	sessions, err := auth.NewSessionManager(st, time.Hour, 24*time.Hour)
+	if err != nil {
+		t.Fatal(err)
+	}
+	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
+	router, err := NewRouter(logger, "dev", nil, stubAuth{}, sessions, household.NewSettingsService(st),
+		fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Sign in as the callback would.
+	login := httptest.NewRecorder()
+	if err := sessions.StartSession(login, httptest.NewRequest(http.MethodGet, "/auth/callback", nil), auth.Claims{
+		Subject: "authentik-sub-42",
+		Email:   "cook@example.com",
+		Name:    "Home Cook",
+		Groups:  []string{"mealquest-admin"},
+	}); err != nil {
+		t.Fatal(err)
+	}
+	cookies := login.Result().Cookies()
+	if len(cookies) != 1 || cookies[0].Name != auth.SessionCookieName {
+		t.Fatalf("StartSession set cookies %v, want the session cookie", cookies)
+	}
+	cookie := cookies[0]
+	withCookie := func(req *http.Request) *http.Request {
+		req.AddCookie(cookie)
+		return req
+	}
+
+	rec, me := serve(t, router, withCookie(httptest.NewRequest(http.MethodGet, "/api/v1/me", nil)))
+	token, _ := me["csrfToken"].(string)
+	if rec.Code != http.StatusOK || token == "" {
+		t.Fatalf("GET /api/v1/me = %d %v, want 200 with a CSRF token", rec.Code, me)
+	}
+
+	patch := `{"dinner_time":"18:45"}`
+	refused := []struct {
+		name   string
+		req    *http.Request
+		status int
+	}{
+		{"no session", httptest.NewRequest(http.MethodPatch, settingsPath, strings.NewReader(patch)), http.StatusUnauthorized},
+		{"no CSRF token", withCookie(httptest.NewRequest(http.MethodPatch, settingsPath, strings.NewReader(patch))), http.StatusForbidden},
+	}
+	for _, tt := range refused {
+		if rec, body := serve(t, router, tt.req); rec.Code != tt.status {
+			t.Errorf("%s: PATCH status = %d, want %d: %v", tt.name, rec.Code, tt.status, body)
+		}
+	}
+	_, body := serve(t, router, withCookie(httptest.NewRequest(http.MethodGet, settingsPath, nil)))
+	if body["dinner_time"] != household.SeedDinnerTime || body["updated_by"] != nil {
+		t.Fatalf("refused PATCH changed settings: %v", body)
+	}
+
+	req := withCookie(httptest.NewRequest(http.MethodPatch, settingsPath, strings.NewReader(patch)))
+	req.Header.Set(CSRFHeader, token)
+	rec, body = serve(t, router, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("PATCH status = %d, want 200: %v", rec.Code, body)
+	}
+	if body["dinner_time"] != "18:45" || body["updated_by"] != "authentik-sub-42" {
+		t.Errorf("PATCH = %v, want dinner_time 18:45 updated_by authentik-sub-42", body)
+	}
+}