From 875eaae7cfc18fef9e69154537331da4dd52affd Mon Sep 17 00:00:00 2001
From: slizco <teamslizco@gmail.com>
Date: Mon, 22 Jul 2024 14:47:58 -0400
Subject: [PATCH] Add v2 svclog unit tests

---
 cmdutil/v2/svclog/logger.go      | 76 +++++---------------------------
 cmdutil/v2/svclog/logger_test.go | 71 +++++++++++++++++++++++++++++
 2 files changed, 81 insertions(+), 66 deletions(-)
 create mode 100644 cmdutil/v2/svclog/logger_test.go

diff --git a/cmdutil/v2/svclog/logger.go b/cmdutil/v2/svclog/logger.go
index c48456f2..3ded974d 100644
--- a/cmdutil/v2/svclog/logger.go
+++ b/cmdutil/v2/svclog/logger.go
@@ -3,6 +3,7 @@ package svclog
 
 import (
 	"fmt"
+	"io"
 	"log"
 	"os"
 
@@ -16,6 +17,8 @@ type Config struct {
 	SpaceID  string `env:"SPACE_ID"`
 	Dyno     string `env:"DYNO"`
 	LogLevel string `env:"LOG_LEVEL,default=INFO"`
+
+	WriteTo io.Writer
 }
 
 // NewLogger returns a new logger that includes app and deploy key/value pairs
@@ -29,7 +32,12 @@ func NewLogger(cfg Config) *slog.Logger {
 	hopts := &slog.HandlerOptions{
 		Level: level,
 	}
-	logger := slog.New(slog.NewTextHandler(os.Stdout, hopts)).With(
+	var w io.Writer
+	w = cfg.WriteTo
+	if w == nil {
+		w = os.Stdout
+	}
+	logger := slog.New(slog.NewTextHandler(w, hopts)).With(
 		"app", cfg.AppName,
 		"deploy", cfg.Deploy,
 	)
@@ -45,7 +53,7 @@ func NewLogger(cfg Config) *slog.Logger {
 }
 
 // ReportPanic attempts to report the panic to rollbar via the slog.
-func ReportPanic(logger slog.Logger) {
+func ReportPanic(logger *slog.Logger) {
 	if p := recover(); p != nil {
 		s := fmt.Sprint(p)
 		logger.With("at", "panic").Error(s)
@@ -53,70 +61,6 @@ func ReportPanic(logger slog.Logger) {
 	}
 }
 
-/*
-// NewSampleLogger creates a rate limited logger that samples logs. The parameter
-// logsBurstLimit defines how many logs are allowed per logBurstWindow duration.
-// The returned logger derives from the parentLogger, but without inheriting any Hooks.
-// All log entries derived from SampleLogger will contain 'sampled=true' field.
-func NewSampleLogger(parentLogger slog.Logger, logsBurstLimit int, logBurstWindow time.Duration) slog.Logger {
-	entry := parentLogger.With("sampled", true)
-	ll := slog.New()
-	ll.Out = entry.Logger.Out
-	ll.Level = entry.Logger.Level
-	ll.ReportCaller = entry.Logger.ReportCaller
-	ll.Formatter = &sampleFormatter{
-		origFormatter: entry.Logger.Formatter,
-		limiter:       rate.NewLimiter(rate.Every(logBurstWindow), logsBurstLimit),
-	}
-
-	return ll.With(entry.Data)
-}
-
-type sampleFormatter struct {
-	limiter       *rate.Limiter
-	origFormatter slog.Formatter
-}
-
-func (sf *sampleFormatter) Format(e *slog.Entry) ([]byte, error) {
-	if sf.limiter.Allow() {
-		return sf.origFormatter.Format(e)
-	}
-
-	return nil, nil
-}
-
-// SaramaLogger takes Logger and returns a saramaLogger.
-func SaramaLogger(logger slog.Logger) slog.Logger {
-	logger = logger.With("component", "sarama")
-	return saramaLogger{logger}
-}
-
-type saramaLogger struct {
-	slog.Logger
-}
-
-func (sl saramaLogger) Printf(format string, args ...interface{}) {
-	format = strings.TrimSpace(format)
-	sl.Logger.Printf(format, args...)
-}
-
-// NewNullLogger returns a logger that discards the output useful for testing
-func NewNullLogger() slog.Logger {
-	logger := slog.New()
-	logger.SetOutput(io.Discard)
-	return logger
-}
-
-// LoggerOrNull ensures non-nil logger is passed in or creates a Null Logger
-func LoggerOrNull(l slog.Logger) slog.Logger {
-	if l == nil {
-		return NewNullLogger()
-	}
-
-	return l
-}
-*/
-
 func ParseLevel(s string) (slog.Level, error) {
 	var level slog.Level
 	var err = level.UnmarshalText([]byte(s))
diff --git a/cmdutil/v2/svclog/logger_test.go b/cmdutil/v2/svclog/logger_test.go
new file mode 100644
index 00000000..5f70dbbb
--- /dev/null
+++ b/cmdutil/v2/svclog/logger_test.go
@@ -0,0 +1,71 @@
+package svclog
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"testing"
+)
+
+func TestLoggerEmitsAppAndDeployData(t *testing.T) {
+	buf := bytes.NewBuffer([]byte{})
+	cfg := Config{
+		AppName:  "sushi",
+		Deploy:   "production",
+		LogLevel: "INFO",
+		Dyno:     "web.1",
+		WriteTo:  buf,
+	}
+	logger := NewLogger(cfg)
+	logger.Info("message")
+
+	expectLogLine(t, buf, map[string]string{
+		"app":    "sushi",
+		"deploy": "production",
+		"msg":    "message",
+		"dyno":   "web.1",
+	})
+}
+
+func TestReportPanic(t *testing.T) {
+	buf := bytes.NewBuffer([]byte{})
+	cfg := Config{
+		AppName:  "sushi",
+		Deploy:   "production",
+		LogLevel: "INFO",
+		Dyno:     "web.1",
+		WriteTo:  buf,
+	}
+	logger := NewLogger(cfg)
+
+	defer func() {
+		if p := recover(); p == nil {
+			t.Fatal("expected ReportPanic to repanic")
+		}
+
+		expectLogLine(t, buf, map[string]string{
+			"msg":   "\"test message\"",
+			"at":    "panic",
+			"level": "ERROR",
+		})
+	}()
+
+	func() {
+		defer ReportPanic(logger)
+
+		panic("test message")
+	}()
+}
+
+func expectLogLine(t *testing.T, buf *bytes.Buffer, m map[string]string) {
+	msg, err := buf.ReadString('\n')
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for k, v := range m {
+		if !strings.Contains(msg, fmt.Sprintf("%s=%s", k, v)) {
+			t.Errorf("expected log line to contain %s=%s", k, v)
+		}
+	}
+}