ApiError throws when response is undefined – fails to handle network/auth errors gracefully #765
Description
SDK you're using (please complete the following information):
Version: 13
Describe the bug
The ApiError class in xero-node does not handle missing response objects from Axios errors, which causes it to throw a secondary error (TypeError: Cannot read property 'status' of undefined) when the underlying cause is something like a network issue, authentication failure, or misconfiguration (e.g. incorrect tenant ID).
To Reproduce
Configure a Xero client with:
An invalid or expired access token
Or a non-existent tenant ID
Make any authenticated request to the API, such as xero.accountingApi.getInvoices(...)
Observe that the request fails, but instead of cleanly reporting the underlying issue, it throws a secondary error due to accessing axiosError.response.status directly when response is undefined.
Expected behavior
ApiError should gracefully handle the absence of a response object in the error, returning a status code of 0 or a sensible fallback value. This would allow users to correctly diagnose configuration or network issues.
Proposed Fix
Update the ApiError constructor in xero-node:
// Current buggy code
this.statusCode = axiosError.response.status;
// Proposed fix
this.statusCode = axiosError.response?.status || 0;
Screenshots / Stack Trace
TypeError: Cannot read property 'status' of undefined
at new ApiError (/node_modules/xero-node/dist/src/XeroClient.js:XXX)
Additional context
In our situation, the request likely failed due to:
An invalid or expired access token
Network issues (API unreachable)
An incorrect tenant ID
This bug suggests that the request never successfully reached Xero's servers. Fixing this would greatly improve developer experience when debugging auth or connectivity issues.