core: Add ctx.Slogger() which returns an slog logger (#5945)

context.go

@@ -19,10 +19,12 @@ import (
 	"encoding/json"
 	"fmt"
 	"log"
+	"log/slog"
 	"reflect"
 
 	"github.com/caddyserver/certmagic"
 	"go.uber.org/zap"
+	"go.uber.org/zap/exp/zapslog"
 
 	"github.com/caddyserver/caddy/v2/internal/filesystems"
 )
@@ -503,6 +505,30 @@ func (ctx Context) Logger(module ...Module) *zap.Logger {
 	return ctx.cfg.Logging.Logger(mod)
 }
 
+// Slogger returns a slog logger that is intended for use by
+// the most recent module associated with the context.
+func (ctx Context) Slogger() *slog.Logger {
+	if ctx.cfg == nil {
+		// often the case in tests; just use a dev logger
+		l, err := zap.NewDevelopment()
+		if err != nil {
+			panic("config missing, unable to create dev logger: " + err.Error())
+		}
+		return slog.New(zapslog.NewHandler(l.Core(), nil))
+	}
+	mod := ctx.Module()
+	if mod == nil {
+		return slog.New(zapslog.NewHandler(Log().Core(), nil))
+	}
+
+	return slog.New(zapslog.NewHandler(
+		ctx.cfg.Logging.Logger(mod).Core(),
+		&zapslog.HandlerOptions{
+			LoggerName: string(mod.CaddyModule().ID),
+		},
+	))
+}
+
 // Modules returns the lineage of modules that this context provisioned,
 // with the most recent/current module being last in the list.
 func (ctx Context) Modules() []Module {

go.mod

@@ -35,6 +35,7 @@ require (
 	go.opentelemetry.io/otel/sdk v1.21.0
 	go.uber.org/automaxprocs v1.5.3
 	go.uber.org/zap v1.26.0
+	go.uber.org/zap/exp v0.2.0
 	golang.org/x/crypto v0.18.0
 	golang.org/x/exp v0.0.0-20231214170342-aacd6d4b4611
 	golang.org/x/net v0.19.0

go.sum

@@ -668,6 +668,8 @@ go.uber.org/zap v1.10.0/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
 go.uber.org/zap v1.13.0/go.mod h1:zwrFLgMcdUuIBviXEYEH1YKNaOBnKXsx2IPda5bBwHM=
 go.uber.org/zap v1.26.0 h1:sI7k6L95XOKS281NhVKOFCUNIvv9e0w4BF8N3u+tCRo=
 go.uber.org/zap v1.26.0/go.mod h1:dtElttAiwGvoJ/vj4IwHBS/gXsEu/pZ50mUIRWuG0so=
+go.uber.org/zap/exp v0.2.0 h1:FtGenNNeCATRB3CmB/yEUnjEFeJWpB/pMcy7e2bKPYs=
+go.uber.org/zap/exp v0.2.0/go.mod h1:t0gqAIdh1MfKv9EwN/dLwfZnJxe9ITAZN78HEWPFWDQ=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20181029021203-45a5f77698d3/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=