Added support for rounding of values by default in API responses

internal/adapters/inbound/httpapi/endpoints_test.go

@@ -119,6 +119,70 @@ func TestObservationsPopulatedJSONEnvelope(t *testing.T) {
 	}
 }
 
+func TestObservationsDefaultPrecisionRoundsToInteger(t *testing.T) {
+	h := newHandler(t, &fakeService{
+		observation: &model.WeatherObservation{
+			Timestamp:     time.Now().UTC(),
+			ConditionCode: model.WMOUnknown,
+			TemperatureC:  float64Ptr(20.6),
+		},
+	}, "/observations")
+
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/observations", nil)
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var payload struct {
+		Data map[string]any `json:"data"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &payload); err != nil {
+		t.Fatalf("decode envelope: %v", err)
+	}
+	got, ok := payload.Data["temperatureC"].(float64)
+	if !ok {
+		t.Fatalf("expected temperatureC float, got %#v", payload.Data["temperatureC"])
+	}
+	if got != 21 {
+		t.Fatalf("expected rounded temperatureC 21, got %v", got)
+	}
+}
+
+func TestObservationsPrecisionTwo(t *testing.T) {
+	h := newHandler(t, &fakeService{
+		observation: &model.WeatherObservation{
+			Timestamp:     time.Now().UTC(),
+			ConditionCode: model.WMOUnknown,
+			TemperatureC:  float64Ptr(20.678),
+		},
+	}, "/observations")
+
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/observations?precision=2", nil)
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var payload struct {
+		Data map[string]any `json:"data"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &payload); err != nil {
+		t.Fatalf("decode envelope: %v", err)
+	}
+	got, ok := payload.Data["temperatureC"].(float64)
+	if !ok {
+		t.Fatalf("expected temperatureC float, got %#v", payload.Data["temperatureC"])
+	}
+	if math.Abs(got-20.68) > 0.00001 {
+		t.Fatalf("expected rounded temperatureC 20.68, got %v", got)
+	}
+}
+
 func TestFormatNegotiationCaseInsensitive(t *testing.T) {
 	hXML := newHandler(t, &fakeService{alerts: &model.WeatherAlertRun{AsOf: time.Now().UTC()}}, "/alerts/active")
 
@@ -285,6 +349,51 @@ func TestForecastUSUnitsWithXMLFormatUppercaseQuery(t *testing.T) {
 	}
 }
 
+func TestForecastPrecisionTwo(t *testing.T) {
+	h := newHandler(t, &fakeService{
+		forecast: &model.WeatherForecastRun{
+			Product:  model.ForecastProductHourly,
+			IssuedAt: time.Now().UTC(),
+			Periods: []model.WeatherForecastPeriod{{
+				StartTime:     time.Now().UTC(),
+				EndTime:       time.Now().UTC().Add(time.Hour),
+				ConditionCode: model.WMOUnknown,
+				TemperatureC:  float64Ptr(12.345),
+			}},
+		},
+	}, "/forecast/hourly")
+
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/forecast/hourly?precision=2", nil)
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var payload struct {
+		Data map[string]any `json:"data"`
+	}
+	if err := json.Unmarshal(w.Body.Bytes(), &payload); err != nil {
+		t.Fatalf("decode envelope: %v", err)
+	}
+	periods, ok := payload.Data["periods"].([]any)
+	if !ok || len(periods) == 0 {
+		t.Fatalf("expected non-empty periods, got %#v", payload.Data["periods"])
+	}
+	first, ok := periods[0].(map[string]any)
+	if !ok {
+		t.Fatalf("expected first period object, got %#v", periods[0])
+	}
+	got, ok := first["temperatureC"].(float64)
+	if !ok {
+		t.Fatalf("expected temperatureC float, got %#v", first["temperatureC"])
+	}
+	if math.Abs(got-12.35) > 0.00001 {
+		t.Fatalf("expected rounded temperatureC 12.35, got %v", got)
+	}
+}
+
 func TestCurrentConditionsNoDataReturnsNullEnvelopeData(t *testing.T) {
 	h := newHandler(t, &fakeService{}, "/conditions/current")
 
@@ -436,6 +545,33 @@ func TestCurrentConditionsRejectUnknownQueryParameter(t *testing.T) {
 	}
 }
 
+func TestPrecisionValidationRange(t *testing.T) {
+	h := newHandler(t, &fakeService{}, "/conditions/current")
+
+	for _, raw := range []string{"-1", "3", "abc"} {
+		w := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodGet, "/conditions/current?precision="+raw, nil)
+		h.ServeHTTP(w, req)
+		if w.Code != http.StatusBadRequest {
+			t.Fatalf("expected 400 for precision=%s, got %d", raw, w.Code)
+		}
+	}
+}
+
+func TestAlertsRejectPrecisionQueryParameter(t *testing.T) {
+	h := newHandler(t, &fakeService{
+		alerts: &model.WeatherAlertRun{AsOf: time.Now().UTC()},
+	}, "/alerts/active")
+
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/alerts/active?precision=1", nil)
+	h.ServeHTTP(w, req)
+
+	if w.Code != http.StatusBadRequest {
+		t.Fatalf("expected 400, got %d", w.Code)
+	}
+}
+
 func newHandler(t *testing.T, svc Service, path string) http.Handler {
 	t.Helper()