feat: add recover middleware

recover middleware wraps other middlewares and recover from panics

recover/recover.go

@@ -0,0 +1,39 @@
+package recover
+
+import (
+	"log"
+	"runtime/debug"
+
+	"github.com/charmbracelet/wish"
+	"github.com/gliderlabs/ssh"
+)
+
+// Middleware is a wish middleware that recovers from panics and log to stderr.
+func Middleware(mw ...wish.Middleware) wish.Middleware {
+	return MiddlewareWithLogger(nil, mw...)
+}
+
+// MiddlewareWithLogger is a wish middleware that recovers from panics and log to
+// the provided logger.
+func MiddlewareWithLogger(logger *log.Logger, mw ...wish.Middleware) wish.Middleware {
+	if logger == nil {
+		logger = log.Default()
+	}
+	h := func(ssh.Session) {}
+	for _, m := range mw {
+		h = m(h)
+	}
+	return func(sh ssh.Handler) ssh.Handler {
+		return func(s ssh.Session) {
+			func() {
+				defer func() {
+					if r := recover(); r != nil {
+						logger.Printf("panic: %v\n%s", r, string(debug.Stack()))
+					}
+				}()
+				h(s)
+			}()
+			sh(s)
+		}
+	}
+}

recover/recover_test.go

@@ -0,0 +1,35 @@
+package recover
+
+import (
+	"testing"
+
+	"github.com/charmbracelet/wish/testsession"
+	"github.com/gliderlabs/ssh"
+	gossh "golang.org/x/crypto/ssh"
+)
+
+func TestMiddleware(t *testing.T) {
+	t.Run("recover session", func(t *testing.T) {
+		_, err := setup(t).Output("")
+		requireNoError(t, err)
+	})
+}
+
+func setup(tb testing.TB) *gossh.Session {
+	tb.Helper()
+	return testsession.New(tb, &ssh.Server{
+		Handler: Middleware(func(h ssh.Handler) ssh.Handler {
+			return func(s ssh.Session) {
+				panic("hello")
+			}
+		})(func(s ssh.Session) {}),
+	}, nil)
+}
+
+func requireNoError(t *testing.T, err error) {
+	t.Helper()
+
+	if err != nil {
+		t.Fatalf("expected no error, got %q", err.Error())
+	}
+}