From 6d84c5b9e3d56d5015f150259bf7fafaf7c894f6 Mon Sep 17 00:00:00 2001
From: Nicola Murino <nicola.murino@gmail.com>
Date: Sun, 3 Jan 2021 10:38:28 +0100
Subject: [PATCH] capture http servers error logs

otherwise they will be printed to stdout
---
 httpd/httpd.go         |  2 ++
 logger/logger.go       | 18 ++++++++++++++++++
 telemetry/telemetry.go |  2 ++
 webdavd/server.go      |  2 ++
 4 files changed, 24 insertions(+)

diff --git a/httpd/httpd.go b/httpd/httpd.go
index 12085850..d9726853 100644
--- a/httpd/httpd.go
+++ b/httpd/httpd.go
@@ -9,6 +9,7 @@ package httpd
 import (
 	"crypto/tls"
 	"fmt"
+	"log"
 	"net/http"
 	"path/filepath"
 	"runtime"
@@ -154,6 +155,7 @@ func (c Conf) Initialize(configDir string) error {
 		WriteTimeout:   60 * time.Second,
 		IdleTimeout:    120 * time.Second,
 		MaxHeaderBytes: 1 << 16, // 64KB
+		ErrorLog:       log.New(&logger.StdLoggerWrapper{Sender: logSender}, "", 0),
 	}
 	if certificateFile != "" && certificateKeyFile != "" {
 		certMgr, err = common.NewCertManager(certificateFile, certificateKeyFile, logSender)
diff --git a/logger/logger.go b/logger/logger.go
index 98014a1a..e87c4aae 100644
--- a/logger/logger.go
+++ b/logger/logger.go
@@ -40,6 +40,24 @@ var (
 	rollingLogger *lumberjack.Logger
 )
 
+// StdLoggerWrapper is a wrapper for standard logger compatibility
+type StdLoggerWrapper struct {
+	Sender string
+}
+
+// Write implements the io.Writer interface. This is useful to set as a writer
+// for the standard library log.
+func (l *StdLoggerWrapper) Write(p []byte) (n int, err error) {
+	n = len(p)
+	if n > 0 && p[n-1] == '\n' {
+		// Trim CR added by stdlog.
+		p = p[0 : n-1]
+	}
+
+	Log(LevelError, l.Sender, "", string(p))
+	return
+}
+
 // GetLogger get the configured logger instance
 func GetLogger() *zerolog.Logger {
 	return &logger
diff --git a/telemetry/telemetry.go b/telemetry/telemetry.go
index 8e43625a..28e1cb57 100644
--- a/telemetry/telemetry.go
+++ b/telemetry/telemetry.go
@@ -6,6 +6,7 @@ package telemetry
 
 import (
 	"crypto/tls"
+	"log"
 	"net/http"
 	"path/filepath"
 	"runtime"
@@ -82,6 +83,7 @@ func (c Conf) Initialize(configDir string) error {
 		WriteTimeout:   60 * time.Second,
 		IdleTimeout:    120 * time.Second,
 		MaxHeaderBytes: 1 << 14, // 16KB
+		ErrorLog:       log.New(&logger.StdLoggerWrapper{Sender: logSender}, "", 0),
 	}
 	if certificateFile != "" && certificateKeyFile != "" {
 		certMgr, err = common.NewCertManager(certificateFile, certificateKeyFile, logSender)
diff --git a/webdavd/server.go b/webdavd/server.go
index 52f81d13..52571b70 100644
--- a/webdavd/server.go
+++ b/webdavd/server.go
@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"errors"
 	"fmt"
+	"log"
 	"net/http"
 	"path"
 	"path/filepath"
@@ -42,6 +43,7 @@ func (s *webDavServer) listenAndServe() error {
 		ReadHeaderTimeout: 30 * time.Second,
 		IdleTimeout:       120 * time.Second,
 		MaxHeaderBytes:    1 << 16, // 64KB
+		ErrorLog:          log.New(&logger.StdLoggerWrapper{Sender: logSender}, "", 0),
 	}
 	if s.config.Cors.Enabled {
 		c := cors.New(cors.Options{