feat: expose daily metric query api

go/vehicle-gateway/internal/stats/query_test.go

@@ -0,0 +1,100 @@
+package stats
+
+import (
+	"context"
+	"database/sql"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/DATA-DOG/go-sqlmock"
+)
+
+func TestMetricRepositoryQueriesDailyMetricsWithFilters(t *testing.T) {
+	db, mock, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("sqlmock.New() error = %v", err)
+	}
+	defer db.Close()
+	mock.ExpectQuery("SELECT vin, stat_date, protocol, metric_key, metric_value, metric_unit, first_total_mileage_km, latest_total_mileage_km, sample_count, calculation_method, created_at, updated_at FROM vehicle_daily_metric").
+		WithArgs("LKLG7C4E3NA774736", "JT808", "2026-07-01", "2026-07-01", 20, 0).
+		WillReturnRows(sqlmock.NewRows([]string{
+			"vin", "stat_date", "protocol", "metric_key", "metric_value", "metric_unit",
+			"first_total_mileage_km", "latest_total_mileage_km", "sample_count", "calculation_method",
+			"created_at", "updated_at",
+		}).AddRow(
+			"LKLG7C4E3NA774736", "2026-07-01", "JT808", MetricDailyTotalMileageKM, 12345.6, "km",
+			12345.6, 12345.6, 13, "TOTAL_MILEAGE_DIFF", "2026-07-01 22:49:11", "2026-07-01 23:09:36",
+		))
+
+	repository := NewMetricRepository(db)
+	rows, err := repository.Query(context.Background(), MetricQuery{
+		VIN:      "LKLG7C4E3NA774736",
+		Protocol: "JT808",
+		DateFrom: "2026-07-01",
+		DateTo:   "2026-07-01",
+		Limit:    20,
+	})
+	if err != nil {
+		t.Fatalf("Query() error = %v", err)
+	}
+	if len(rows) != 1 {
+		t.Fatalf("row count = %d", len(rows))
+	}
+	if rows[0].MetricKey != MetricDailyTotalMileageKM || rows[0].MetricValue != 12345.6 {
+		t.Fatalf("unexpected row: %#v", rows[0])
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Fatalf("sql expectations: %v", err)
+	}
+}
+
+func TestMetricHandlerReturnsDailyMetrics(t *testing.T) {
+	db, mock, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("sqlmock.New() error = %v", err)
+	}
+	defer db.Close()
+	mock.ExpectQuery("SELECT vin, stat_date, protocol, metric_key, metric_value, metric_unit, first_total_mileage_km, latest_total_mileage_km, sample_count, calculation_method, created_at, updated_at FROM vehicle_daily_metric").
+		WithArgs("LB9A32A21R0LS1707", "GB32960", "2020-07-01", "2020-07-01", 50, 0).
+		WillReturnRows(sqlmock.NewRows([]string{
+			"vin", "stat_date", "protocol", "metric_key", "metric_value", "metric_unit",
+			"first_total_mileage_km", "latest_total_mileage_km", "sample_count", "calculation_method",
+			"created_at", "updated_at",
+		}).AddRow(
+			"LB9A32A21R0LS1707", "2020-07-01", "GB32960", MetricDailyMileageKM, 0.0, "km",
+			53490.9, 53490.9, 3, "TOTAL_MILEAGE_DIFF", "2026-07-01 22:07:58", "2026-07-01 22:28:25",
+		))
+
+	handler := NewMetricHandler(NewMetricRepository(db))
+	request := httptest.NewRequest(http.MethodGet, "/api/stats/daily-metrics?vin=LB9A32A21R0LS1707&protocol=GB32960&dateFrom=2020-07-01&dateTo=2020-07-01", nil)
+	response := httptest.NewRecorder()
+
+	handler.ServeHTTP(response, request)
+
+	if response.Code != http.StatusOK {
+		t.Fatalf("status = %d body=%s", response.Code, response.Body.String())
+	}
+	body := response.Body.String()
+	for _, want := range []string{`"vin":"LB9A32A21R0LS1707"`, `"metric_key":"daily_mileage_km"`, `"total":1`} {
+		if !strings.Contains(body, want) {
+			t.Fatalf("response missing %s: %s", want, body)
+		}
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Fatalf("sql expectations: %v", err)
+	}
+}
+
+func TestMetricHandlerRejectsInvalidPagination(t *testing.T) {
+	handler := NewMetricHandler(NewMetricRepository(&sql.DB{}))
+	request := httptest.NewRequest(http.MethodGet, "/api/stats/daily-metrics?limit=2001", nil)
+	response := httptest.NewRecorder()
+
+	handler.ServeHTTP(response, request)
+
+	if response.Code != http.StatusBadRequest {
+		t.Fatalf("status = %d body=%s", response.Code, response.Body.String())
+	}
+}