go: change how logger is initialised

* init in run.go
* use slogger instead of slog in main
* print different messages based on whether we're initialising or
  re-initialising slogger..

config/config.go

@@ -110,6 +110,7 @@ func Load(conf string, isPath bool) (*Config, error) {
 	slogger := slogging.Logger()
 	// initialise if not already initialised.
 	if slogger == nil {
+		/// this should never happen, as the logger is initialised in run.go.
 		slogger = slogging.Init(true)
 	}
 

main.go

@@ -7,13 +7,16 @@ import (
 	"os"
 
 	"git.dotya.ml/mirre-mt/pcmt/slogging"
-	"golang.org/x/exp/slog"
 )
 
 func main() {
 	err := run()
 	if err != nil {
-		l := slog.New(slog.NewJSONHandler(os.Stderr, slogging.Opts()))
+		l := slogging.Logger()
+		if l == nil {
+			l = slogging.Init(true)
+		}
+
 		l.Error("unrecoverable failure, stopping the app", "error", err)
 		os.Exit(1)
 	}

run.go

@@ -97,6 +97,17 @@ func run() error { //nolint:gocognit
 		printHeader()
 	}
 
+	slogger = slogging.Logger()
+	if slogger == nil {
+		slogger = slogging.Init(true)
+	}
+
+	log = *slogger // local copy.
+	log.Logger = log.Logger.With(
+		// local attrs.
+		slog.Group("pcmt extra", slog.String("module", "run")),
+	)
+
 	// TODO: allow different configuration formats (toml, ini)
 	// TODO: rename main.go to pcmt.go
 	// TODO: add flake.nix
@@ -120,13 +131,6 @@ func run() error { //nolint:gocognit
 		conf, host, port, devel, version,
 	)
 
-	slogger = slogging.Logger() // init is performed in the config package.
-	log = *slogger              // local copy.
-	log.Logger = log.Logger.With(
-		// local attrs.
-		slog.Group("pcmt extra", slog.String("module", "run")),
-	)
-
 	// expected connstring form for "github.com/xiaoqidun/entps":
 	// "file:ent?mode=memory&cache=shared&_fk=1"
 	// and for the postgres driver "github.com/lib/pq":

slogging/log.go

@@ -21,9 +21,11 @@ const (
 	LevelError
 )
 
-var logger *Slogger
-
-var opts *slog.HandlerOptions
+var (
+	logger      *Slogger
+	opts        *slog.HandlerOptions
+	initialised = false
+)
 
 func Opts() *slog.HandlerOptions {
 	return opts
@@ -46,7 +48,12 @@ func Init(jsonHandler bool) *Slogger {
 
 	slog.SetDefault(logger.Logger)
 
-	logger.Info("slog logger initialised")
+	if initialised {
+		logger.Info("slog logger reinitialised")
+	} else {
+		initialised = true
+		logger.Info("slog logger initialised")
+	}
 
 	return logger
 }