Implement self-update recovery (T-403)

app-modern/cmd/softboxupdater/main.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"softbox.local/app-modern/platform/windows"
+	"softbox.local/core/updater"
+)
+
+func main() {
+	if err := run(os.Args[1:]); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run(arguments []string) error {
+	for _, option := range []string{"--pid", "--staging", "--target"} {
+		if err := requireOneOption(arguments, option); err != nil {
+			return err
+		}
+	}
+	flags := flag.NewFlagSet("SoftBoxUpdater", flag.ContinueOnError)
+	flags.SetOutput(io.Discard)
+	pid := flags.Int("pid", 0, "main SoftBox PID")
+	staging := flags.String("staging", "", "prepared staging directory")
+	target := flags.String("target", "", "fixed app target directory")
+	if err := flags.Parse(arguments); err != nil {
+		return fmt.Errorf("parse updater arguments: %w", err)
+	}
+	if flags.NArg() != 0 || *pid <= 0 || *staging == "" || *target == "" || !filepath.IsAbs(*staging) || !filepath.IsAbs(*target) {
+		return fmt.Errorf("usage: SoftBoxUpdater --pid <positive PID> --staging <absolute staging directory> --target <absolute root/app>")
+	}
+	requestID := filepath.Base(filepath.Clean(*staging))
+	platform := windows.New()
+	service := updater.NewService(platform, platform, platform, updater.FileHealthWaiter{}, updater.Timeouts{
+		ParentExit: 2 * time.Minute,
+		Health:     45 * time.Second,
+	})
+	return service.Update(context.Background(), updater.Request{
+		ParentPID: *pid, StagingDir: *staging, TargetDir: *target, RequestID: requestID,
+	})
+}
+
+func requireOneOption(arguments []string, option string) error {
+	count := 0
+	for _, argument := range arguments {
+		if argument == option || strings.HasPrefix(argument, option+"=") {
+			count++
+		}
+	}
+	if count != 1 {
+		return fmt.Errorf("%s must appear exactly once", option)
+	}
+	return nil
+}

app-modern/cmd/softboxupdater/main_test.go

@@ -0,0 +1,14 @@
+package main
+
+import "testing"
+
+func TestRunRejectsIncompleteAndDuplicateArguments(t *testing.T) {
+	if err := run(nil); err == nil {
+		t.Fatal("run(nil) succeeded")
+	}
+	if err := run([]string{
+		"--pid", "1", "--pid", "2", "--staging", "/root/staging/update-1234", "--target", "/root/app",
+	}); err == nil {
+		t.Fatal("run() accepted duplicate --pid")
+	}
+}