feat(observability): slog-backed logging, Prometheus metrics, grpc health

- internal/logging now wraps log/slog; logging.format json/text finally works (json is the documented default). Same exported API. - New internal/metrics: /metrics on the configured metrics port with notification gauges by status/type, queue depth, and HTTP request count/duration labeled by mux route pattern; sampled from service stats so the service layer stays metrics-agnostic. - Standard grpc.health.v1 health service registered (k8s gRPC probes); gRPC MaxRecvMsgSize bounded to match the REST 1 MB body limit. - Dedicated health listener on health_check.port serving /health and /readyz (probes now work in grpc-only mode); metrics, health, and REST servers all shut down gracefully. - main wires retry backoff, CORS, readiness checks, and TLS from config. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-18 09:16:12 -07:00
parent ee82522b7c
commit 72f154ab07
5 changed files with 637 additions and 71 deletions
@@ -0,0 +1,221 @@
+package logging
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestNew_TextFormat(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "text.log")
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
+	if err != nil {
+		t.Fatalf("unexpected error opening file: %v", err)
+	}
+	defer file.Close()
+
+	logger := New(InfoLevel, file)
+	logger.Info("hello world")
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("failed to read log file: %v", err)
+	}
+	out := string(data)
+
+	if !strings.Contains(out, "hello world") {
+		t.Fatalf("expected output to contain message, got: %q", out)
+	}
+	if !strings.Contains(out, "level=INFO") {
+		t.Fatalf("expected text output to contain level=INFO, got: %q", out)
+	}
+	if json.Valid(data) {
+		t.Fatalf("expected non-JSON text output, got JSON: %q", out)
+	}
+}
+
+func TestNewFromConfig_JSONOutput(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "json.log")
+
+	logger, err := NewFromConfig("info", path)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	logger.Info("structured message")
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("failed to read log file: %v", err)
+	}
+
+	var payload map[string]interface{}
+	if err := json.Unmarshal(data, &payload); err != nil {
+		t.Fatalf("expected valid JSON output, got error %v; output: %q", err, string(data))
+	}
+
+	if payload["msg"] != "structured message" {
+		t.Fatalf("expected msg field to equal message, got: %v", payload["msg"])
+	}
+	if payload["level"] != "INFO" {
+		t.Fatalf("expected level field INFO, got: %v", payload["level"])
+	}
+	timeVal, ok := payload["time"].(string)
+	if !ok {
+		t.Fatalf("expected time field to be a string, got: %v", payload["time"])
+	}
+	if _, err := time.Parse(time.RFC3339, timeVal); err != nil {
+		t.Fatalf("expected time field to be RFC3339, got %q: %v", timeVal, err)
+	}
+}
+
+func TestLevelFiltering_DebugSuppressedAtInfo(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "level.log")
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
+	if err != nil {
+		t.Fatalf("unexpected error opening file: %v", err)
+	}
+	defer file.Close()
+
+	logger := New(InfoLevel, file)
+	logger.Debug("should not appear")
+	logger.Info("should appear")
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("failed to read log file: %v", err)
+	}
+	out := string(data)
+
+	if strings.Contains(out, "should not appear") {
+		t.Fatalf("expected debug message to be suppressed, got: %q", out)
+	}
+	if !strings.Contains(out, "should appear") {
+		t.Fatalf("expected info message to be present, got: %q", out)
+	}
+}
+
+func TestNewFromOptions_FileOutput(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "out.log")
+
+	logger, err := NewFromOptions("info", "json", path)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	logger.Info("file message")
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("failed to read log file: %v", err)
+	}
+
+	var payload map[string]interface{}
+	if err := json.Unmarshal(data, &payload); err != nil {
+		t.Fatalf("expected valid JSON in file, got error %v; contents: %q", err, string(data))
+	}
+	if payload["msg"] != "file message" {
+		t.Fatalf("expected msg field, got: %v", payload["msg"])
+	}
+}
+
+func TestNewFromOptions_FormatSelection(t *testing.T) {
+	dir := t.TempDir()
+
+	jsonPath := filepath.Join(dir, "json.log")
+	jsonLogger, err := NewFromOptions("info", "json", jsonPath)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	jsonLogger.Info("json message")
+
+	jsonData, err := os.ReadFile(jsonPath)
+	if err != nil {
+		t.Fatalf("failed to read json log file: %v", err)
+	}
+	if !json.Valid(jsonData) {
+		t.Fatalf("expected valid JSON, got: %q", string(jsonData))
+	}
+
+	textPath := filepath.Join(dir, "text.log")
+	textLogger, err := NewFromOptions("info", "text", textPath)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	textLogger.Info("text message")
+
+	textData, err := os.ReadFile(textPath)
+	if err != nil {
+		t.Fatalf("failed to read text log file: %v", err)
+	}
+	if json.Valid(textData) {
+		t.Fatalf("expected non-JSON text output, got: %q", string(textData))
+	}
+	if !strings.Contains(string(textData), `msg="text message"`) {
+		t.Fatalf("expected text output to contain msg attribute, got: %q", string(textData))
+	}
+
+	// Default format ("" -> json) via NewFromOptions.
+	defaultPath := filepath.Join(dir, "default.log")
+	defaultLogger, err := NewFromOptions("info", "", defaultPath)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	defaultLogger.Info("default message")
+
+	defaultData, err := os.ReadFile(defaultPath)
+	if err != nil {
+		t.Fatalf("failed to read default log file: %v", err)
+	}
+	if !json.Valid(defaultData) {
+		t.Fatalf("expected empty format to default to JSON, got: %q", string(defaultData))
+	}
+
+	// NewFromConfig should also default to JSON.
+	configPath := filepath.Join(dir, "config.log")
+	configLogger, err := NewFromConfig("info", configPath)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	configLogger.Info("config message")
+
+	configData, err := os.ReadFile(configPath)
+	if err != nil {
+		t.Fatalf("failed to read config log file: %v", err)
+	}
+	if !json.Valid(configData) {
+		t.Fatalf("expected NewFromConfig to default to JSON format, got: %q", string(configData))
+	}
+}
+
+func TestSlogAccessor(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "slog.log")
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
+	if err != nil {
+		t.Fatalf("unexpected error opening file: %v", err)
+	}
+	defer file.Close()
+
+	logger := New(InfoLevel, file)
+	if logger.Slog() == nil {
+		t.Fatal("expected Slog() to return a non-nil *slog.Logger")
+	}
+
+	logger.Slog().Info("via slog accessor")
+
+	data, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("failed to read log file: %v", err)
+	}
+	if !strings.Contains(string(data), "via slog accessor") {
+		t.Fatalf("expected message logged via Slog() accessor, got: %q", string(data))
+	}
+}