weaviate/weaviate · warning

marshal ids: %w

Error message

marshal ids: %w

What it means

FetchObjects marshals the []strfmt.UUID id list to JSON before base64-encoding it into the query string. Marshalling UUIDs is effectively infallible for valid input, so this error only fires with a malformed/nil-constructed id slice element (e.g. a custom MarshalJSON on the type failing).

Source

Thrown at adapters/clients/replication.go:660

			return nil, err
		}
		return nil, fmt.Errorf("status code: %v, error: %s", res.StatusCode, b)
	}

	var resp []types.RepairResponse
	if err := json.NewDecoder(res.Body).Decode(&resp); err != nil {
		return nil, fmt.Errorf("decode response: %w", err)
	}
	return resp, nil
}

func (c *replicationClient) FetchObjects(ctx context.Context, host,
	index, shard string, ids []strfmt.UUID,
) ([]replica.Replica, error) {
	resp := make(replica.Replicas, len(ids))
	idsBytes, err := json.Marshal(ids)
	if err != nil {
		return nil, fmt.Errorf("marshal ids: %w", err)
	}

	idsEncoded := base64.StdEncoding.EncodeToString(idsBytes)

	req, err := newHttpReplicaRequest(ctx, http.MethodGet, host, index, shard, "", "", nil, 0)
	if err != nil {
		return nil, fmt.Errorf("create http request: %w", err)
	}

	req.URL.RawQuery = url.Values{"ids": []string{idsEncoded}}.Encode()
	err = c.doCustomUnmarshal(c.timeoutUnit*COMMIT_TIMEOUT_VALUE, req, nil, resp.UnmarshalBinary, MAX_RETRIES)
	return resp, err
}

func (c *replicationClient) PutObject(ctx context.Context, host, index,
	shard, requestID string, obj *storobj.Object, schemaVersion uint64,
) (replica.SimpleResponse, error) {
	var resp replica.SimpleResponse

View on GitHub (pinned to 75aa4b6d11)

Solutions

1. Validate each id with strfmt UUID parsing (uuid.Validate / IsUUID) before calling FetchObjects.
2. Trace where the id slice was built; find the element with invalid content.
3. Fix upstream producers to only append parsed strfmt.UUID values.

Example fix

// before
resp, err := client.FetchObjects(ctx, host, index, shard, ids)
// after
for i, id := range ids {
    if err := id.Validate(); err != nil {
        return fmt.Errorf("invalid uuid at index %d: %w", i, err)
    }
}
resp, err := client.FetchObjects(ctx, host, index, shard, ids)

for i, id := range ids {
    if id == "" || len(id) != 36 { return fmt.Errorf("invalid uuid at index %d", i) }
}

func validUUIDs(ids []strfmt.UUID) bool {
    for _, id := range ids {
        if err := id.Validate(); err != nil { return false }
    }
    return true
}

if !validUUIDs(ids) { return errors.New("id list contains invalid UUIDs") }
replicas, err := client.FetchObjects(ctx, host, index, shard, ids)
if err != nil { return err }

When it happens

Trigger: Passing a []strfmt.UUID containing a value whose JSON marshalling fails — practically only possible with corrupted UUID values or misuse of the strfmt type.

Common situations: Programmatic callers building the id list from unvalidated input; bugs upstream where non-UUID data was stored in the id slice.

Related errors

• marshal status request: %w
• marshal abort request: %w
• marshal prepare request: %w
• encode async-checkpoint create body: %w
• encode async-checkpoint delete body: %w

AI-assisted analysis of weaviate/weaviate@75aa4b6d11 (2026-09-04). Data as JSON: /api/errors/f56d62d91a1a472a. Report an issue: GitHub.