fix: skip cleanup for non-2xx status (#1877)

## What kind of change does this PR introduce?
* Skip the cleanup function if the status returned from the
`ResponseWriter` is a non-2xx code
* Refactor the cleanup method to be passed as an interface into
`databaseCleanup` to make it easier to test

Author: kangmingtay

internal/api/middleware.go

@@ -11,6 +11,7 @@ import (
 	"sync"
 	"time"
 
+	chimiddleware "github.com/go-chi/chi/v5/middleware"
 	"github.com/sirupsen/logrus"
 	"github.com/supabase/auth/internal/models"
 	"github.com/supabase/auth/internal/observability"
@@ -245,15 +246,18 @@ func (a *API) requireManualLinkingEnabled(w http.ResponseWriter, req *http.Reque
 	return ctx, nil
 }
 
-func (a *API) databaseCleanup(cleanup *models.Cleanup) func(http.Handler) http.Handler {
+func (a *API) databaseCleanup(cleanup models.Cleaner) func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			next.ServeHTTP(w, r)
-
+			wrappedResp := chimiddleware.NewWrapResponseWriter(w, r.ProtoMajor)
+			next.ServeHTTP(wrappedResp, r)
 			switch r.Method {
 			case http.MethodPost, http.MethodPut, http.MethodPatch, http.MethodDelete:
+				if (wrappedResp.Status() / 100) != 2 {
+					// don't do any cleanups for non-2xx responses
+					return
+				}
 				// continue
-
 			default:
 				return
 			}

internal/api/middleware_test.go

@@ -14,9 +14,11 @@ import (
 	"github.com/didip/tollbooth/v5/limiter"
 	jwt "github.com/golang-jwt/jwt/v5"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
 	"github.com/supabase/auth/internal/conf"
+	"github.com/supabase/auth/internal/storage"
 )
 
 const (
@@ -443,3 +445,66 @@ func (ts *MiddlewareTestSuite) TestLimitHandler() {
 	ts.API.limitHandler(lmt).handler(okHandler).ServeHTTP(w, req)
 	require.Equal(ts.T(), http.StatusTooManyRequests, w.Code)
 }
+
+type MockCleanup struct {
+	mock.Mock
+}
+
+func (m *MockCleanup) Clean(db *storage.Connection) (int, error) {
+	m.Called(db)
+	return 0, nil
+}
+
+func (ts *MiddlewareTestSuite) TestDatabaseCleanup() {
+	testHandler := func(statusCode int) http.HandlerFunc {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.WriteHeader(statusCode)
+			b, _ := json.Marshal(map[string]interface{}{"message": "ok"})
+			w.Write([]byte(b))
+		})
+	}
+
+	cases := []struct {
+		desc       string
+		statusCode int
+		method     string
+	}{
+		{
+			desc:       "Run cleanup successfully",
+			statusCode: http.StatusOK,
+			method:     http.MethodPost,
+		},
+		{
+			desc:       "Skip cleanup if GET",
+			statusCode: http.StatusOK,
+			method:     http.MethodGet,
+		},
+		{
+			desc:       "Skip cleanup if 3xx",
+			statusCode: http.StatusSeeOther,
+			method:     http.MethodPost,
+		},
+		{
+			desc:       "Skip cleanup if 4xx",
+			statusCode: http.StatusBadRequest,
+			method:     http.MethodPost,
+		},
+		{
+			desc:       "Skip cleanup if 5xx",
+			statusCode: http.StatusInternalServerError,
+			method:     http.MethodPost,
+		},
+	}
+
+	mockCleanup := new(MockCleanup)
+	mockCleanup.On("Clean", mock.Anything).Return(0, nil)
+	for _, c := range cases {
+		ts.Run("DatabaseCleanup", func() {
+			req := httptest.NewRequest(c.method, "http://localhost", nil)
+			w := httptest.NewRecorder()
+			ts.API.databaseCleanup(mockCleanup)(testHandler(c.statusCode)).ServeHTTP(w, req)
+			require.Equal(ts.T(), c.statusCode, w.Code)
+		})
+	}
+	mockCleanup.AssertNumberOfCalls(ts.T(), "Clean", 1)
+}

internal/models/cleanup.go

@@ -16,6 +16,10 @@ import (
 	"github.com/supabase/auth/internal/storage"
 )
 
+type Cleaner interface {
+	Clean(*storage.Connection) (int, error)
+}
+
 type Cleanup struct {
 	cleanupStatements []string