logging.Base()

Allow users to get access to the base logger *before* it is wrapped with the various levels.
This provides a single override point to filter or redirect all logging.

12 files changed, 77 insertions, 59 deletions

diff --git a/examples/cgi/main.go b/examples/cgi/main.go
index 4d48422..587c874 100644
--- a/examples/cgi/main.go
+++ b/examples/cgi/main.go
@@ -7,6 +7,7 @@ import (
 	"os/signal"
 	"syscall"
 
+	"github.com/go-kit/log/level"
 	"tildegit.org/tjp/sliderule/contrib/cgi"
 	"tildegit.org/tjp/sliderule/gemini"
 	"tildegit.org/tjp/sliderule/logging"
@@ -25,17 +26,17 @@ func main() {
 	// make use of a CGI request handler
 	cgiHandler := cgi.GeminiCGIDirectory("./cgi-bin", "/cgi-bin")
 
-	_, infoLog, _, errLog := logging.DefaultLoggers()
+	baseLog := logging.Base()
 
 	// add stdout logging to the request handler
-	handler := logging.LogRequests(infoLog)(cgiHandler)
+	handler := logging.LogRequests(level.Info(baseLog))(cgiHandler)
 
 	// set up signals to trigger graceful shutdown
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGHUP)
 	defer stop()
 
 	// run the server
-	server, err := gemini.NewServer(ctx, "localhost", "tcp4", ":1965", handler, errLog, tlsconf)
+	server, err := gemini.NewServer(ctx, "localhost", "tcp4", ":1965", handler, baseLog, tlsconf)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/examples/cowsay/main.go b/examples/cowsay/main.go
index 32ba2ea..3ada714 100644
--- a/examples/cowsay/main.go
+++ b/examples/cowsay/main.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"os/exec"
 
+	"github.com/go-kit/log/level"
 	sr "tildegit.org/tjp/sliderule"
 	"tildegit.org/tjp/sliderule/gemini"
 	"tildegit.org/tjp/sliderule/logging"
@@ -23,13 +24,13 @@ func main() {
 		log.Fatal(err)
 	}
 
-	_, infoLog, _, errLog := logging.DefaultLoggers()
+	baseLog := logging.Base()
 
 	// add request logging to the request handler
-	handler := logging.LogRequests(infoLog)(cowsayHandler)
+	handler := logging.LogRequests(level.Info(baseLog))(cowsayHandler)
 
 	// run the server
-	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, errLog, tlsconf)
+	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, baseLog, tlsconf)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/examples/fileserver/main.go b/examples/fileserver/main.go
index e90fdd9..2801858 100644
--- a/examples/fileserver/main.go
+++ b/examples/fileserver/main.go
@@ -5,6 +5,7 @@ import (
 	"log"
 	"os"
 
+	"github.com/go-kit/log/level"
 	sr "tildegit.org/tjp/sliderule"
 	"tildegit.org/tjp/sliderule/contrib/fs"
 	"tildegit.org/tjp/sliderule/gemini"
@@ -35,13 +36,13 @@ func main() {
 	router.Route("/*", handler)
 	handler = router.Handler()
 
-	_, infoLog, _, errLog := logging.DefaultLoggers()
+	baseLog := logging.Base()
 
 	// add request logging to stdout
-	handler = logging.LogRequests(infoLog)(handler)
+	handler = logging.LogRequests(level.Info(baseLog))(handler)
 
 	// run the server
-	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, errLog, tlsconf)
+	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, baseLog, tlsconf)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/examples/finger/main.go b/examples/finger/main.go
index 723e3e6..8cb6526 100644
--- a/examples/finger/main.go
+++ b/examples/finger/main.go
@@ -4,20 +4,20 @@ import (
 	"context"
 	"log"
 
+	"github.com/go-kit/log/level"
 	"tildegit.org/tjp/sliderule/finger"
 	"tildegit.org/tjp/sliderule/logging"
 )
 
 func main() {
-	_, infoLog, _, errLog := logging.DefaultLoggers()
-
+	baselog := logging.Base()
 	fs, err := finger.NewServer(
 		context.Background(),
 		"localhost",
 		"tcp",
 		":79",
-		logging.LogRequests(infoLog)(finger.SystemFinger(false)),
-		errLog,
+		logging.LogRequests(level.Info(baselog))(finger.SystemFinger(false)),
+		logging.Base(),
 	)
 	if err != nil {
 		log.Fatal(err)
diff --git a/examples/gopher_fileserver/main.go b/examples/gopher_fileserver/main.go
index 1cb7495..9b8c33f 100644
--- a/examples/gopher_fileserver/main.go
+++ b/examples/gopher_fileserver/main.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"log"
 
+	"github.com/go-kit/log/level"
 	sr "tildegit.org/tjp/sliderule"
 	"tildegit.org/tjp/sliderule/contrib/cgi"
 	"tildegit.org/tjp/sliderule/contrib/fs"
@@ -19,10 +20,10 @@ func main() {
 		fs.GopherFileHandler(".", "", nil),
 	)
 
-	_, infoLog, _, errLog := logging.DefaultLoggers()
-	handler = logging.LogRequests(infoLog)(handler)
+	baseLog := logging.Base()
+	handler = logging.LogRequests(level.Info(baseLog))(handler)
 
-	server, err := gopher.NewServer(context.Background(), "localhost", "tcp4", ":70", handler, errLog)
+	server, err := gopher.NewServer(context.Background(), "localhost", "tcp4", ":70", handler, baseLog)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/examples/inspectls/main.go b/examples/inspectls/main.go
index d400fe9..f12fd65 100644
--- a/examples/inspectls/main.go
+++ b/examples/inspectls/main.go
@@ -12,6 +12,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/go-kit/log/level"
 	sr "tildegit.org/tjp/sliderule"
 	"tildegit.org/tjp/sliderule/gemini"
 	"tildegit.org/tjp/sliderule/logging"
@@ -27,13 +28,13 @@ func main() {
 		log.Fatal(err)
 	}
 
-	_, infoLog, _, errLog := logging.DefaultLoggers()
+	baseLog := logging.Base()
 
 	// add stdout logging to the request handler
-	handler := logging.LogRequests(infoLog)(inspectHandler)
+	handler := logging.LogRequests(level.Info(baseLog))(inspectHandler)
 
 	// run the server
-	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, errLog, tlsconf)
+	server, err := gemini.NewServer(context.Background(), "localhost", "tcp4", ":1965", handler, baseLog, tlsconf)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/finger/serve.go b/finger/serve.go
index ff842e1..db96088 100644
--- a/finger/serve.go
+++ b/finger/serve.go
@@ -25,7 +25,7 @@ func NewServer(
 	network string,
 	address string,
 	handler types.Handler,
-	errLog logging.Logger,
+	baseLog logging.Logger,
 ) (types.Server, error) {
 	fs := &fingerServer{handler: handler}
 
@@ -33,7 +33,7 @@ func NewServer(
 	address = internal.JoinDefaultPort(address, "79")
 
 	var err error
-	fs.Server, err = internal.NewServer(ctx, hostname, network, address, errLog, fs.handleConn)
+	fs.Server, err = internal.NewServer(ctx, hostname, network, address, baseLog, fs.handleConn)
 	if err != nil {
 		return nil, err
 	}
diff --git a/gemini/serve.go b/gemini/serve.go
index 5c6c979..0303c13 100644
--- a/gemini/serve.go
+++ b/gemini/serve.go
@@ -31,7 +31,7 @@ func NewServer(
 	network string,
 	address string,
 	handler types.Handler,
-	errorLog logging.Logger,
+	baseLog logging.Logger,
 	tlsConfig *tls.Config,
 ) (types.Server, error) {
 	s := &server{handler: handler}
@@ -39,7 +39,7 @@ func NewServer(
 	hostname = internal.JoinDefaultPort(hostname, "1965")
 	address = internal.JoinDefaultPort(address, "1965")
 
-	internalServer, err := internal.NewServer(ctx, hostname, network, address, errorLog, s.handleConn)
+	internalServer, err := internal.NewServer(ctx, hostname, network, address, baseLog, s.handleConn)
 	if err != nil {
 		return nil, err
 	}
diff --git a/gopher/serve.go b/gopher/serve.go
index d78150c..67c889a 100644
--- a/gopher/serve.go
+++ b/gopher/serve.go
@@ -26,7 +26,7 @@ func NewServer(
 	network string,
 	address string,
 	handler types.Handler,
-	errLog logging.Logger,
+	baseLog logging.Logger,
 ) (types.Server, error) {
 	gs := &gopherServer{handler: handler}
 
@@ -34,7 +34,7 @@ func NewServer(
 	address = internal.JoinDefaultPort(address, "70")
 
 	var err error
-	gs.Server, err = internal.NewServer(ctx, hostname, network, address, errLog, gs.handleConn)
+	gs.Server, err = internal.NewServer(ctx, hostname, network, address, baseLog, gs.handleConn)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/server.go b/internal/server.go
index a95efc1..21d1a7f 100644
--- a/internal/server.go
+++ b/internal/server.go
@@ -6,20 +6,18 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/go-kit/log"
+	"github.com/go-kit/log/level"
 	"tildegit.org/tjp/sliderule/logging"
 )
 
-type logger interface {
-	Log(keyvals ...any) error
-}
-
 type Server struct {
 	Ctx         context.Context
 	Cancel      context.CancelFunc
 	Wg          *sync.WaitGroup
 	Listener    net.Listener
 	HandleConn  connHandler
-	ErrorLog    logger
+	ErrorLog    logging.Logger
 	Host        string
 	NetworkAddr net.Addr
 }
@@ -31,7 +29,7 @@ func NewServer(
 	hostname string,
 	network string,
 	address string,
-	errorLog logger,
+	baseLog logging.Logger,
 	handleConn connHandler,
 ) (Server, error) {
 	listener, err := net.Listen(network, address)
@@ -42,10 +40,13 @@ func NewServer(
 	networkAddr := listener.Addr()
 	ctx, cancel := context.WithCancel(ctx)
 
-	debuglog, infolog, warnlog, errlog := logging.DefaultLoggers()
-	ctx = context.WithValue(ctx, "debuglog", debuglog)
-	ctx = context.WithValue(ctx, "infolog", infolog)
-	ctx = context.WithValue(ctx, "warnlog", warnlog)
+	if baseLog == nil {
+		baseLog = log.NewNopLogger()
+	}
+	errlog := level.Error(baseLog)
+	ctx = context.WithValue(ctx, "debuglog", level.Debug(baseLog))
+	ctx = context.WithValue(ctx, "infolog", level.Info(baseLog))
+	ctx = context.WithValue(ctx, "warnlog", level.Warn(baseLog))
 	ctx = context.WithValue(ctx, "errlog", errlog)
 
 	return Server{
@@ -54,7 +55,7 @@ func NewServer(
 		Wg:          &sync.WaitGroup{},
 		Listener:    listener,
 		HandleConn:  handleConn,
-		ErrorLog:    errorLog,
+		ErrorLog:    errlog,
 		Host:        hostname,
 		NetworkAddr: networkAddr,
 	}, nil
diff --git a/logging/logger.go b/logging/logger.go
index 87b5985..084bea0 100644
--- a/logging/logger.go
+++ b/logging/logger.go
@@ -2,6 +2,7 @@ package logging
 
 import (
 	"os"
+	"sync"
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
@@ -13,31 +14,42 @@ type Logger interface {
 	Log(keyvals ...any) error
 }
 
-// DefaultLoggers produces helpful base loggers for each level.
-//
-// They write logfmt to standard out, annotated with ANSI colors depending on the level.
-func DefaultLoggers() (debug, info, warn, error Logger) {
-	base := term.NewLogger(os.Stdout, log.NewLogfmtLogger, func(keyvals ...any) term.FgBgColor {
-		for i := 0; i < len(keyvals)-1; i += 2 {
-			if keyvals[i] != "level" {
-				continue
-			}
+var (
+	once       sync.Once
+	baselogger Logger
+)
 
-			switch keyvals[i+1] {
-			case level.DebugValue():
-				return term.FgBgColor{Fg: term.Gray}
-			case level.InfoValue():
-				return term.FgBgColor{Fg: term.Green}
-			case level.WarnValue():
-				return term.FgBgColor{Fg: term.Yellow}
-			case level.ErrorValue():
-				return term.FgBgColor{Fg: term.Red}
+func Base() Logger {
+	once.Do(func() {
+		base := term.NewLogger(os.Stdout, log.NewLogfmtLogger, func(keyvals ...any) term.FgBgColor {
+			for i := 0; i < len(keyvals)-1; i += 2 {
+				if keyvals[i] != "level" {
+					continue
+				}
+
+				switch keyvals[i+1] {
+				case level.DebugValue():
+					return term.FgBgColor{Fg: term.Gray}
+				case level.InfoValue():
+					return term.FgBgColor{Fg: term.Green}
+				case level.WarnValue():
+					return term.FgBgColor{Fg: term.Yellow}
+				case level.ErrorValue():
+					return term.FgBgColor{Fg: term.Red}
+				}
 			}
-		}
 
-		return term.FgBgColor{}
+			return term.FgBgColor{}
+		})
+		baselogger = log.NewSyncLogger(base)
 	})
-	base = log.NewSyncLogger(base)
+	return baselogger
+}
 
+// DefaultLoggers produces helpful base loggers for each level.
+//
+// They write logfmt to standard out, annotated with ANSI colors depending on the level.
+func DefaultLoggers() (debug, info, warn, error Logger) {
+	base := Base()
 	return level.Debug(base), level.Info(base), level.Warn(base), level.Error(base)
 }
diff --git a/spartan/serve.go b/spartan/serve.go
index 4b37f6a..0fb4939 100644
--- a/spartan/serve.go
+++ b/spartan/serve.go
@@ -27,7 +27,7 @@ func NewServer(
 	network string,
 	address string,
 	handler types.Handler,
-	errLog logging.Logger,
+	baseLog logging.Logger,
 ) (types.Server, error) {
 	ss := &spartanServer{handler: handler}
 
@@ -35,7 +35,7 @@ func NewServer(
 	address = internal.JoinDefaultPort(address, "300")
 
 	var err error
-	ss.Server, err = internal.NewServer(ctx, hostname, network, address, errLog, ss.handleConn)
+	ss.Server, err = internal.NewServer(ctx, hostname, network, address, baseLog, ss.handleConn)
 	if err != nil {
 		return nil, err
 	}