fix: make document::Create more resilient if subsequent patch call receives 404

We call PATCH immediately after POST when creating a document in order to make it public.
However, it can be the case that the subsequent call to the PATCH endpoint happens to early. In this situation the API returns 404 and the call to Create fails. To make this more resilient, a retry mechanism was added.

Signed-off-by: Bernd Warmuth <[email protected]>

Author: Bernd Warmuth

clients/documents/documents.go

@@ -28,6 +28,7 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
+	"time"
 
 	"github.com/dynatrace/dynatrace-configuration-as-code-core/api"
 	"github.com/dynatrace/dynatrace-configuration-as-code-core/api/clients/documents"
@@ -215,14 +216,15 @@ func (c Client) Create(ctx context.Context, name string, isPrivate bool, externa
 		return api.Response{}, err
 	}
 
-	r, err := c.patch(ctx, md.ID, md.Version, d)
+	r, err := c.patchWithRetry(ctx, md.ID, md.Version, d)
 	if err != nil {
-		if _, err1 := c.delete(ctx, md.ID, md.Version); err1 != nil {
-			return api.Response{}, errors.Join(err, err1)
+		if !isNotFoundError(err) {
+			if _, err1 := c.delete(ctx, md.ID, md.Version); err1 != nil {
+				return api.Response{}, errors.Join(err, err1)
+			}
 		}
 		return api.Response{}, err
 	}
-
 	return r, nil
 }
 
@@ -275,6 +277,24 @@ func (c Client) create(ctx context.Context, d documents.Document) (api.Response,
 	return processHttpResponse(c.client.Create(ctx, d))
 }
 
+func (c Client) patchWithRetry(ctx context.Context, id string, version int, d documents.Document) (resp api.Response, err error) {
+	const maxRetries = 5
+	const retryDelay = 200 * time.Millisecond
+	for r := 0; r < maxRetries; r++ {
+		if resp, err = c.patch(ctx, id, version, d); isNotFoundError(err) {
+			time.Sleep(retryDelay)
+			continue
+		}
+		break
+	}
+	return
+}
+
+func isNotFoundError(err error) bool {
+	var apiErr api.APIError
+	return errors.As(err, &apiErr) && apiErr.StatusCode == http.StatusNotFound
+}
+
 func (c Client) patch(ctx context.Context, id string, version int, d documents.Document) (api.Response, error) {
 	resp, err := processHttpResponse(c.client.Patch(ctx, id, version, d))
 	if err != nil {

clients/documents/documents_test.go

@@ -230,6 +230,44 @@ func TestDocumentClient_Create(t *testing.T) {
 		assert.ErrorContains(t, err, "some internal error")
 	})
 
+	t.Run("patch call returns 404 - retry succeeds", func(t *testing.T) {
+		ctx := testutils.ContextWithLogger(t)
+		mockClient := documents.NewMockclient(gomock.NewController(t))
+		mockClient.EXPECT().Create(ctx, givenDoc).
+			Return(&http.Response{Status: http.StatusText(http.StatusCreated), StatusCode: http.StatusCreated, Body: io.NopCloser(strings.NewReader(respCreate)), Request: &http.Request{Method: http.MethodGet, URL: &url.URL{}}}, nil)
+		mockClient.EXPECT().Patch(ctx, "f6e26fdd-1451-4655-b6ab-1240a00c1fba", 1, givenDoc).Times(4).
+			Return(&http.Response{Status: http.StatusText(http.StatusNotFound), StatusCode: http.StatusNotFound, Body: io.NopCloser(strings.NewReader("some internal error")), Request: &http.Request{Method: http.MethodPatch, URL: &url.URL{}}}, nil)
+		mockClient.EXPECT().Patch(ctx, "f6e26fdd-1451-4655-b6ab-1240a00c1fba", 1, givenDoc).
+			Return(&http.Response{Status: http.StatusText(http.StatusOK), StatusCode: http.StatusOK, Body: io.NopCloser(strings.NewReader(respPatch)), Request: &http.Request{Method: http.MethodPatch, URL: &url.URL{}}}, nil)
+
+		docClient := documents.NewTestClient(mockClient)
+
+		res, err := docClient.Create(ctx, "name", false, "extID", []byte("this is the content"), documents.Notebook)
+
+		require.NoError(t, err)
+		assert.JSONEq(t, expected, string(res.Data))
+	})
+
+	t.Run("patch call returns 404 - retry fails", func(t *testing.T) {
+		ctx := testutils.ContextWithLogger(t)
+		mockClient := documents.NewMockclient(gomock.NewController(t))
+		mockClient.EXPECT().Create(ctx, givenDoc).
+			Return(&http.Response{Status: http.StatusText(http.StatusCreated), StatusCode: http.StatusCreated, Body: io.NopCloser(strings.NewReader(respCreate)), Request: &http.Request{Method: http.MethodGet, URL: &url.URL{}}}, nil)
+		mockClient.EXPECT().Patch(ctx, "f6e26fdd-1451-4655-b6ab-1240a00c1fba", 1, givenDoc).Times(5).
+			Return(&http.Response{Status: http.StatusText(http.StatusNotFound), StatusCode: http.StatusNotFound, Body: io.NopCloser(strings.NewReader("some internal error")), Request: &http.Request{Method: http.MethodPatch, URL: &url.URL{}}}, nil)
+
+		docClient := documents.NewTestClient(mockClient)
+
+		res, err := docClient.Create(ctx, "name", false, "extID", []byte("this is the content"), documents.Notebook)
+
+		require.Empty(t, res)
+		require.Error(t, err)
+
+		// var apiErr api.APIError
+		assert.ErrorAs(t, err, &api.APIError{})
+		assert.ErrorContains(t, err, "API request HTTP PATCH  failed with status code 404")
+	})
+
 	t.Run("patch call returns non successful response; rollback fails", func(t *testing.T) {
 		ctx := testutils.ContextWithLogger(t)
 		mockClient := documents.NewMockclient(gomock.NewController(t))