initial commit

logging/logger.go

@@ -0,0 +1,121 @@
+package logging
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/go-chi/chi/middleware"
+	"github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
+)
+
+var Logger *logrus.Logger
+
+// StructuredLogger is a structured logrus Logger.
+type StructuredLogger struct {
+	Logger *logrus.Logger
+}
+
+// NewLogger creates and configures a new logrus Logger.
+func NewLogger() *logrus.Logger {
+	Logger = logrus.New()
+	if viper.GetBool("log_textlogging") {
+		Logger.Formatter = &logrus.TextFormatter{
+			DisableTimestamp: true,
+		}
+	} else {
+		Logger.Formatter = &logrus.JSONFormatter{
+			DisableTimestamp: true,
+		}
+	}
+
+	level := viper.GetString("log_level")
+	if level == "" {
+		level = "error"
+	}
+	l, err := logrus.ParseLevel(level)
+	if err != nil {
+		panic(err)
+	}
+	Logger.Level = l
+	return Logger
+}
+
+// NewStructuredLogger implements a custom structured logrus Logger.
+func NewStructuredLogger(logger *logrus.Logger) func(next http.Handler) http.Handler {
+	return middleware.RequestLogger(&StructuredLogger{Logger})
+}
+
+func (l *StructuredLogger) NewLogEntry(r *http.Request) middleware.LogEntry {
+	entry := &StructuredLoggerEntry{Logger: logrus.NewEntry(l.Logger)}
+	logFields := logrus.Fields{}
+
+	logFields["ts"] = time.Now().UTC().Format(time.RFC1123)
+
+	if reqID := middleware.GetReqID(r.Context()); reqID != "" {
+		logFields["req_id"] = reqID
+	}
+
+	scheme := "http"
+	if r.TLS != nil {
+		scheme = "https"
+	}
+
+	logFields["http_scheme"] = scheme
+	logFields["http_proto"] = r.Proto
+	logFields["http_method"] = r.Method
+
+	logFields["remote_addr"] = r.RemoteAddr
+	logFields["user_agent"] = r.UserAgent()
+
+	logFields["uri"] = fmt.Sprintf("%s://%s%s", scheme, r.Host, r.RequestURI)
+	logFields["uri"] = fmt.Sprintf("%s", r.RequestURI)
+
+	entry.Logger = entry.Logger.WithFields(logFields)
+
+	entry.Logger.Infoln("request started")
+
+	return entry
+}
+
+type StructuredLoggerEntry struct {
+	Logger logrus.FieldLogger
+}
+
+func (l *StructuredLoggerEntry) Write(status, bytes int, elapsed time.Duration) {
+	l.Logger = l.Logger.WithFields(logrus.Fields{
+		"resp_status":       status,
+		"resp_bytes_length": bytes,
+		"resp_elasped_ms":   float64(elapsed.Nanoseconds()) / 1000000.0,
+	})
+
+	l.Logger.Infoln("request complete")
+}
+
+func (l *StructuredLoggerEntry) Panic(v interface{}, stack []byte) {
+	l.Logger = l.Logger.WithFields(logrus.Fields{
+		"stack": string(stack),
+		"panic": fmt.Sprintf("%+v", v),
+	})
+}
+
+// Helper methods used by the application to get the request-scoped
+// logger entry and set additional fields between handlers.
+
+func GetLogEntry(r *http.Request) logrus.FieldLogger {
+	entry := middleware.GetLogEntry(r).(*StructuredLoggerEntry)
+	return entry.Logger
+}
+
+func LogEntrySetField(r *http.Request, key string, value interface{}) {
+	if entry, ok := r.Context().Value(middleware.LogEntryCtxKey).(*StructuredLoggerEntry); ok {
+		entry.Logger = entry.Logger.WithField(key, value)
+	}
+}
+
+func LogEntrySetFields(r *http.Request, fields map[string]interface{}) {
+	if entry, ok := r.Context().Value(middleware.LogEntryCtxKey).(*StructuredLoggerEntry); ok {
+		entry.Logger = entry.Logger.WithFields(fields)
+	}
+}