feat: backend native executor implement

internal/hostnginx/controller_test.go

@@ -0,0 +1,103 @@
+package hostnginx
+
+import (
+	"context"
+	"errors"
+	"os"
+	"path/filepath"
+	"slices"
+	"testing"
+)
+
+func TestControllerSwitchesAndReloadsExactService(t *testing.T) {
+	configPath := writeNginxConfig(t, serverConfiguration)
+	runner := &recordingRunner{}
+	controller, err := newController(configPath, "/usr/sbin/nginx", "/bin/systemctl", "nginx.service", runner)
+	if err != nil {
+		t.Fatalf("create host Nginx controller: %v", err)
+	}
+
+	previous, err := controller.Switch(context.Background(), 8080)
+	if err != nil {
+		t.Fatalf("switch host Nginx backend: %v", err)
+	}
+	if previous.ActivePort != 8081 {
+		t.Fatalf("unexpected previous port: %d", previous.ActivePort)
+	}
+	current, err := controller.Read()
+	if err != nil || current.ActivePort != 8080 {
+		t.Fatalf("unexpected current host Nginx configuration: snapshot=%+v err=%v", current, err)
+	}
+	wantCalls := [][]string{
+		{"/usr/sbin/nginx", "-t"},
+		{"/bin/systemctl", "reload", "--", "nginx.service"},
+	}
+	if !slices.EqualFunc(runner.calls, wantCalls, slices.Equal) {
+		t.Fatalf("unexpected host Nginx commands: %+v", runner.calls)
+	}
+}
+
+func TestControllerRestoresConfigurationWhenValidationFails(t *testing.T) {
+	configPath := writeNginxConfig(t, serverConfiguration)
+	runner := &recordingRunner{errors: []error{errors.New("nginx test failed"), nil, nil}}
+	controller, err := newController(configPath, "/usr/sbin/nginx", "/bin/systemctl", "nginx.service", runner)
+	if err != nil {
+		t.Fatalf("create host Nginx controller: %v", err)
+	}
+
+	if _, err := controller.Switch(context.Background(), 8080); err == nil {
+		t.Fatal("expected host Nginx validation failure")
+	}
+	current, err := controller.Read()
+	if err != nil || current.ActivePort != 8081 || string(current.Content) != serverConfiguration {
+		t.Fatalf("host Nginx configuration was not restored: snapshot=%+v err=%v", current, err)
+	}
+	if len(runner.calls) != 3 {
+		t.Fatalf("unexpected validation compensation calls: %+v", runner.calls)
+	}
+}
+
+func TestControllerRestoreUsesCompleteSnapshot(t *testing.T) {
+	configPath := writeNginxConfig(t, serverConfiguration)
+	runner := &recordingRunner{}
+	controller, err := newController(configPath, "/usr/sbin/nginx", "/bin/systemctl", "nginx.service", runner)
+	if err != nil {
+		t.Fatalf("create host Nginx controller: %v", err)
+	}
+	previous, err := controller.Switch(context.Background(), 8080)
+	if err != nil {
+		t.Fatalf("switch host Nginx backend: %v", err)
+	}
+	if err := controller.Restore(context.Background(), previous); err != nil {
+		t.Fatalf("restore host Nginx backend: %v", err)
+	}
+	current, err := controller.Read()
+	if err != nil || current.ActivePort != 8081 || string(current.Content) != serverConfiguration {
+		t.Fatalf("unexpected restored configuration: snapshot=%+v err=%v", current, err)
+	}
+}
+
+func writeNginxConfig(t *testing.T, content string) string {
+	t.Helper()
+	path := filepath.Join(t.TempDir(), "nginx.conf")
+	if err := os.WriteFile(path, []byte(content), 0o640); err != nil {
+		t.Fatalf("write host Nginx configuration: %v", err)
+	}
+	return path
+}
+
+type recordingRunner struct {
+	calls  [][]string
+	errors []error
+}
+
+func (r *recordingRunner) Run(_ context.Context, executable string, arguments ...string) error {
+	call := append([]string{executable}, arguments...)
+	r.calls = append(r.calls, call)
+	if len(r.errors) == 0 {
+		return nil
+	}
+	err := r.errors[0]
+	r.errors = r.errors[1:]
+	return err
+}