use contexts for logging

2 files changed, 36 insertions, 5 deletions

diff --git a/nslcd_server/ctx.go b/nslcd_server/ctx.go
index 5214adc..9722017 100644
--- a/nslcd_server/ctx.go
+++ b/nslcd_server/ctx.go
@@ -20,9 +20,26 @@ package nslcd_server
 import (
 	"context"
 
+	"git.lukeshu.com/go/libsystemd/sd_daemon"
 	"golang.org/x/sys/unix"
 )
 
+// Logger is the common interface between
+// `"git.lukeshu.com/go/libsystemd/sd_daemon".Logger` and
+// `"log/syslog".Writer`.
+type Logger interface {
+	Emerg(m string) error
+	Alert(m string) error
+	Crit(m string) error
+	Err(m string) error
+	Warning(m string) error
+	Notice(m string) error
+	Info(m string) error
+	Debug(m string) error
+
+	Write(m []byte) (int, error)
+}
+
 // contextKey is a value for use with context.WithValue.  It's used as
 // a pointer so it fits in an interface{} without allocation.
 type contextKey struct {
@@ -35,6 +52,11 @@ var (
 	// The associated value will be of type
 	// "golang.org/x/sys/unix".Ucred
 	PeerCredKey = &contextKey{"peercred"}
+
+	// LoggerKey is a context key.  It can be used in the backend
+	// methods to access a logger.  The associated value will be
+	// an implementation of Logger.
+	LoggerKey = &contextKey{"log"}
 )
 
 // PeerCredFromContext is a convenience function for
@@ -44,3 +66,11 @@ func PeerCredFromContext(ctx context.Context) (unix.Ucred, bool) {
 	cred, ok := ctx.Value(PeerCredKey).(unix.Ucred)
 	return cred, ok
 }
+
+func LoggerFromContext(ctx context.Context) Logger {
+	logger, ok := ctx.Value(LoggerKey).(Logger)
+	if !ok {
+		return sd_daemon.Log
+	}
+	return logger
+}
diff --git a/nslcd_server/func_handlerequest.go.gen b/nslcd_server/func_handlerequest.go.gen
index 750a7b0..8abfb01 100755
--- a/nslcd_server/func_handlerequest.go.gen
+++ b/nslcd_server/func_handlerequest.go.gen
@@ -28,7 +28,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"os"
 	"time"
 
 	p "git.lukeshu.com/go/libnslcd/nslcd_proto"
@@ -109,6 +108,8 @@ func HandleRequest(backend Backend, limits Limits, conn Conn, ctx context.Contex
 		}
 	}
 
+	log := LoggerFromContext(ctx)
+
 	var in io.Reader = conn
 	if limits.RequestMaxSize > 0 {
 		in = &io.LimitedReader{R: in, N: limits.RequestMaxSize}
@@ -135,7 +136,7 @@ while read -r request; do
 			PAM_Authentication)
 				echo '_req := req'
 				echo '_req.Password = sensitive'
-				echo 'fmt.Fprintf(os.Stderr, "Request: %#v\n", _req)'
+				echo 'log.Info(fmt.Sprintf("Request: %#v\n", _req))'
 				;;
 			PAM_PwMod)
 				echo '_req := req'
@@ -143,15 +144,15 @@ while read -r request; do
 				echo '	_req.OldPassword = sensitive'
 				echo '}'
 				echo '_req.NewPassword = sensitive'
-				echo 'fmt.Fprintf(os.Stderr, "Request: %#v\n", _req)'
+				echo 'log.Info(fmt.Sprintf("Request: %#v", _req))'
 				;;
 			PAM_UserMod)
 				echo '_req := req'
 				echo '_req.Password = sensitive'
-				echo 'fmt.Fprintf(os.Stderr, "Request: %#v\n", _req)'
+				echo 'log.Info(fmt.Sprintf("Request: %#v", _req))'
 				;;
 			*)
-				echo 'fmt.Fprintf(os.Stderr, "Request: %#v\n", req)'
+				echo 'log.Info(fmt.Sprintf("Request: %#v", req))'
 				;;
 		esac
 		)