chore: Convert to log/slog (#519)

The small amount of verbose logging in the exec command has been
converted to debug logging under log/slog.

cmd/exec.go

@@ -3,6 +3,7 @@ package cmd
 import (
 	"errors"
 	"fmt"
+	"log/slog"
 	"os"
 	"strings"
 
@@ -97,15 +98,13 @@ func execRun(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("Failed to get secret store: %w", err)
 	}
 
-	if pristine && verbose {
-		fmt.Fprintf(os.Stderr, "chamber: pristine mode engaged\n")
+	if pristine {
+		slog.Debug("chamber: pristine mode engaged")
 	}
 
 	var env environ.Environ
 	if strict {
-		if verbose {
-			fmt.Fprintf(os.Stderr, "chamber: strict mode engaged\n")
-		}
+		slog.Debug("chamber: strict mode engaged")
 		var err error
 		env = environ.Environ(os.Environ())
 		err = env.LoadStrict(cmd.Context(), secretStore, strictValue, pristine, services...)
@@ -130,9 +129,7 @@ func execRun(cmd *cobra.Command, args []string) error {
 		}
 	}
 
-	if verbose {
-		fmt.Fprintf(os.Stdout, "info: With environment %s\n", strings.Join(env, ","))
-	}
+	slog.Debug(fmt.Sprintf("info: With environment %s\n", strings.Join(env, ",")))
 
 	return exec(command, commandArgs, env)
 }

cmd/root.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"log/slog"
 	"os"
 	"regexp"
 	"strconv"
@@ -79,12 +80,13 @@ var RootCmd = &cobra.Command{
 func init() {
 	RootCmd.PersistentFlags().IntVarP(&numRetries, "retries", "r", DefaultNumRetries, "For SSM or Secrets Manager, the number of retries we'll make before giving up; AKA $CHAMBER_RETRIES")
 	RootCmd.PersistentFlags().DurationVarP(&minThrottleDelay, "min-throttle-delay", "", 0, "DEPRECATED and no longer has any effect. Use retry-mode instead")
+	_ = RootCmd.PersistentFlags().MarkDeprecated("min-throttle-delay", "use --retry-mode instead")
 	RootCmd.PersistentFlags().StringVarP(&retryMode, "retry-mode", "", store.DefaultRetryMode.String(),
 		`For SSM, the model used to retry requests
   `+aws.RetryModeStandard.String()+`
   `+aws.RetryModeAdaptive.String(),
 	)
-	RootCmd.PersistentFlags().BoolVarP(&verbose, "verbose", "", false, "Print more information to STDOUT")
+	RootCmd.PersistentFlags().BoolVarP(&verbose, "verbose", "", false, "Print more information to STDERR")
 	RootCmd.PersistentFlags().StringVarP(&backendFlag, "backend", "b", "ssm",
 		`Backend to use; AKA $CHAMBER_SECRET_BACKEND
 	null: no-op
@@ -250,6 +252,13 @@ func prerun(cmd *cobra.Command, args []string) {
 				Set("chamber-version", chamberVersion),
 		})
 	}
+
+	if verbose {
+		levelVar := &slog.LevelVar{}
+		levelVar.Set(slog.LevelDebug)
+		handler := slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{Level: levelVar})
+		slog.SetDefault(slog.New(handler))
+	}
 }
 
 func postrun(cmd *cobra.Command, args []string) {