feat: lazy sprintf

.golangci.yml

@@ -101,9 +101,9 @@ linters:
             - Print
             - Printf
             - Warn
-            - Warnf
             - Fatal
             - Fatalf
+            - LazySprintf
     misspell:
       locale: US
       ignore-rules:

cmd/cmd_renew.go

@@ -382,7 +382,7 @@ func needRenewal(x509Cert *x509.Certificate, domain string, days int, dynamic bo
 		return true
 	}
 
-	log.Info(fmt.Sprintf("Skip renewal: the certificate expires in %d days, the number of days defined to perform the renewal is %d.",
+	log.Infof(log.LazySprintf("Skip renewal: the certificate expires in %d days, the number of days defined to perform the renewal is %d.",
 		notAfter, days), "domain", domain)
 
 	return false
@@ -402,7 +402,7 @@ func needRenewalDynamic(x509Cert *x509.Certificate, domain string, now time.Time
 		return true
 	}
 
-	log.Info(fmt.Sprintf("Skip renewal: The certificate expires at %s, the renewal can be performed in %s.",
+	log.Infof(log.LazySprintf("Skip renewal: The certificate expires at %s, the renewal can be performed in %s.",
 		x509Cert.NotAfter.Format(time.RFC3339), dueDate.Sub(now)), "domain", domain)
 
 	return false

cmd/setup.go

@@ -202,7 +202,7 @@ func checkRetry(ctx context.Context, resp *http.Response, err error) (bool, erro
 			}
 
 		default:
-			log.Warn(fmt.Sprintf("retry: %v", errorDetails))
+			log.Warnf(log.LazySprintf("retry: %v", errorDetails))
 
 			return rt, errorDetails
 		}

cmd/setup_challenges.go

@@ -170,7 +170,7 @@ func setupDNS(ctx *cli.Context, client *lego.Client) error {
 
 func checkPropagationExclusiveOptions(ctx *cli.Context) error {
 	if ctx.IsSet(flgDNSDisableCP) {
-		log.Warn(fmt.Sprintf("The flag '%s' is deprecated use '%s' instead.", flgDNSDisableCP, flgDNSPropagationDisableANS))
+		log.Warnf(log.LazySprintf("The flag '%s' is deprecated use '%s' instead.", flgDNSDisableCP, flgDNSPropagationDisableANS))
 	}
 
 	if (isSetBool(ctx, flgDNSDisableCP) || isSetBool(ctx, flgDNSPropagationDisableANS)) && ctx.IsSet(flgDNSPropagationWait) {

log/lazy.go

@@ -0,0 +1,51 @@
+package log
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+)
+
+type LazyMessage struct {
+	msg  string
+	args []any
+}
+
+func LazySprintf(msg string, args ...any) LazyMessage {
+	return LazyMessage{
+		msg:  msg,
+		args: args,
+	}
+}
+
+func (l LazyMessage) String() string {
+	return fmt.Sprintf(l.msg, l.args...)
+}
+
+// Debugf calls [Logger.Debug] on the default logger.
+func Debugf(msg LazyMessage, args ...any) {
+	logLazy(slog.LevelDebug, msg, args...)
+}
+
+// Infof calls [Logger.Info] on the default logger.
+func Infof(msg LazyMessage, args ...any) {
+	logLazy(slog.LevelInfo, msg, args...)
+}
+
+// Warnf calls [Logger.Warn] on the default logger.
+func Warnf(msg LazyMessage, args ...any) {
+	logLazy(slog.LevelWarn, msg, args...)
+}
+
+// Errorf calls [Logger.Error] on the default logger.
+func Errorf(msg LazyMessage, args ...any) {
+	logLazy(slog.LevelError, msg, args...)
+}
+
+func logLazy(level slog.Level, msg LazyMessage, args ...any) {
+	ctx := context.Background()
+
+	if Default().Enabled(ctx, level) {
+		Default().Log(ctx, level, msg.String(), args...)
+	}
+}

platform/wait/wait.go

@@ -11,7 +11,7 @@ import (
 
 // For polls the given function 'f', once every 'interval', up to 'timeout'.
 func For(msg string, timeout, interval time.Duration, f func() (bool, error)) error {
-	log.Info(fmt.Sprintf("Wait for %s.", msg), "timeout", timeout, "interval", interval)
+	log.Infof(log.LazySprintf("Wait for %s.", msg), "timeout", timeout, "interval", interval)
 
 	var lastErr error
 

providers/dns/cloudns/cloudns.go

@@ -176,7 +176,7 @@ func (d *DNSProvider) waitNameservers(ctx context.Context, domain string, zone *
 				return fmt.Errorf("nameserver sync on %s: %w", domain, err)
 			}
 
-			log.Info(fmt.Sprintf("Sync %d/%d complete", syncProgress.Updated, syncProgress.Total), "domain", domain)
+			log.Infof(log.LazySprintf("Sync %d/%d complete", syncProgress.Updated, syncProgress.Total), "domain", domain)
 
 			if !syncProgress.Complete {
 				return fmt.Errorf("nameserver sync on %s not complete", domain)

providers/dns/hetzner/hetzner.go

@@ -3,7 +3,6 @@ package hetzner
 
 import (
 	"errors"
-	"fmt"
 	"net/http"
 	"time"
 
@@ -119,7 +118,7 @@ func NewDNSProviderConfig(config *Config) (*DNSProvider, error) {
 		return &DNSProvider{provider: provider}, nil
 
 	case config.APIKey != "":
-		log.Warn(fmt.Sprintf("%s (legacy Hetzner DNS API) is deprecated, please use %s (Hetzner Cloud API) instead.", EnvAPIKey, EnvAPIToken))
+		log.Warnf(log.LazySprintf("%s (legacy Hetzner DNS API) is deprecated, please use %s (Hetzner Cloud API) instead.", EnvAPIKey, EnvAPIToken))
 
 		cfg := &legacy.Config{
 			APIKey:             config.APIKey,

providers/dns/namecheap/namecheap.go

@@ -164,7 +164,7 @@ func (d *DNSProvider) Present(domain, token, keyAuth string) error {
 	records = append(records, record)
 
 	for _, h := range records {
-		log.Debug(fmt.Sprintf("%-5.5s %-30.30s %-6s %-70.70s", h.Type, h.Name, h.TTL, h.Address))
+		log.Debugf(log.LazySprintf("%-5.5s %-30.30s %-6s %-70.70s", h.Type, h.Name, h.TTL, h.Address))
 	}
 
 	err = d.client.SetHosts(ctx, pr.sld, pr.tld, records)