feat: add panic recovery middleware (#3687)

coderd/httpmw/recover_test.go

@@ -0,0 +1,74 @@
+package httpmw_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"cdr.dev/slog/sloggers/slogtest"
+	"github.com/coder/coder/coderd/httpapi"
+	"github.com/coder/coder/coderd/httpmw"
+)
+
+func TestRecover(t *testing.T) {
+	t.Parallel()
+
+	handler := func(isPanic, hijack bool) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			if isPanic {
+				panic("Oh no!")
+			}
+
+			w.WriteHeader(http.StatusOK)
+		})
+	}
+
+	cases := []struct {
+		Name   string
+		Code   int
+		Panic  bool
+		Hijack bool
+	}{
+		{
+			Name:   "OK",
+			Code:   http.StatusOK,
+			Panic:  false,
+			Hijack: false,
+		},
+		{
+			Name:   "Panic",
+			Code:   http.StatusInternalServerError,
+			Panic:  true,
+			Hijack: false,
+		},
+		{
+			Name:   "Hijack",
+			Code:   0,
+			Panic:  true,
+			Hijack: true,
+		},
+	}
+
+	for _, c := range cases {
+		c := c
+
+		t.Run(c.Name, func(t *testing.T) {
+			t.Parallel()
+
+			var (
+				log = slogtest.Make(t, nil)
+				r   = httptest.NewRequest("GET", "/", nil)
+				w   = &httpapi.StatusWriter{
+					ResponseWriter: httptest.NewRecorder(),
+					Hijacked:       c.Hijack,
+				}
+			)
+
+			httpmw.Recover(log)(handler(c.Panic, c.Hijack)).ServeHTTP(w, r)
+
+			require.Equal(t, c.Code, w.Status)
+		})
+	}
+}