feat: user service

user/internal/api/internalhttp/observability_test.go

@@ -0,0 +1,112 @@
+package internalhttp
+
+import (
+	"bytes"
+	"context"
+	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"galaxy/user/internal/service/authdirectory"
+	usertelemetry "galaxy/user/internal/telemetry"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/otel/attribute"
+	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/metric/metricdata"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/sdk/trace/tracetest"
+)
+
+func TestInternalHandlerEmitsTraceFieldsAndMetrics(t *testing.T) {
+	t.Parallel()
+
+	logger, buffer := newObservedLogger()
+	telemetryRuntime, reader, recorder := newObservedInternalTelemetryRuntime(t)
+	handler := mustNewHandler(t, Dependencies{
+		Logger:    logger,
+		Telemetry: telemetryRuntime,
+		ExistsByUserID: existsByUserIDFunc(func(context.Context, authdirectory.ExistsByUserIDInput) (authdirectory.ExistsByUserIDResult, error) {
+			return authdirectory.ExistsByUserIDResult{Exists: true}, nil
+		}),
+	})
+
+	recorderHTTP := httptest.NewRecorder()
+	request := httptest.NewRequest(http.MethodGet, "/api/v1/internal/users/user-123/exists", nil)
+	request.Header.Set("traceparent", "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01")
+
+	handler.ServeHTTP(recorderHTTP, request)
+
+	require.Equal(t, http.StatusOK, recorderHTTP.Code)
+	require.NotEmpty(t, recorder.Ended())
+	assert.Contains(t, buffer.String(), "otel_trace_id")
+	assert.Contains(t, buffer.String(), "otel_span_id")
+
+	assertMetricCount(t, reader, "user.internal_http.requests", map[string]string{
+		"route":        "/api/v1/internal/users/:user_id/exists",
+		"method":       http.MethodGet,
+		"edge_outcome": "success",
+	}, 1)
+}
+
+func newObservedInternalTelemetryRuntime(t *testing.T) (*usertelemetry.Runtime, *sdkmetric.ManualReader, *tracetest.SpanRecorder) {
+	t.Helper()
+
+	reader := sdkmetric.NewManualReader()
+	meterProvider := sdkmetric.NewMeterProvider(sdkmetric.WithReader(reader))
+	recorder := tracetest.NewSpanRecorder()
+	tracerProvider := sdktrace.NewTracerProvider(sdktrace.WithSpanProcessor(recorder))
+
+	runtime, err := usertelemetry.NewWithProviders(meterProvider, tracerProvider)
+	require.NoError(t, err)
+
+	return runtime, reader, recorder
+}
+
+func newObservedLogger() (*slog.Logger, *bytes.Buffer) {
+	buffer := &bytes.Buffer{}
+	return slog.New(slog.NewJSONHandler(buffer, &slog.HandlerOptions{Level: slog.LevelDebug})), buffer
+}
+
+func assertMetricCount(t *testing.T, reader *sdkmetric.ManualReader, metricName string, wantAttrs map[string]string, wantValue int64) {
+	t.Helper()
+
+	var resourceMetrics metricdata.ResourceMetrics
+	require.NoError(t, reader.Collect(context.Background(), &resourceMetrics))
+
+	for _, scopeMetrics := range resourceMetrics.ScopeMetrics {
+		for _, metric := range scopeMetrics.Metrics {
+			if metric.Name != metricName {
+				continue
+			}
+
+			sum, ok := metric.Data.(metricdata.Sum[int64])
+			require.True(t, ok)
+
+			for _, point := range sum.DataPoints {
+				if hasMetricAttributes(point.Attributes.ToSlice(), wantAttrs) {
+					assert.Equal(t, wantValue, point.Value)
+					return
+				}
+			}
+		}
+	}
+
+	require.Failf(t, "test failed", "metric %q with attrs %v not found", metricName, wantAttrs)
+}
+
+func hasMetricAttributes(values []attribute.KeyValue, want map[string]string) bool {
+	if len(values) != len(want) {
+		return false
+	}
+
+	for _, value := range values {
+		if want[string(value.Key)] != value.Value.AsString() {
+			return false
+		}
+	}
+
+	return true
+}