httpErrorMessage not properly stringified

[Pipo93]

Describe the bug
We received more than 100 warning logs today where it is impossible to detect the actual root cause for the error: ["2022-11-09T03:40:00.141Z"] Received I/O error ([object Object]) for streaming request - will retry.

Looks like in https://github.com/launchdarkly/node-server-sdk/blob/main/messages.js#L10 the error object is not properly stringified.

To reproduce
It is hard to reproduce on our side but it should be possible by calling httpErrorMessage with an error object not containing a message.

Expected behavior
The actual error is properly logged to the warning message.

Logs
["2022-11-09T03:40:00.141Z"] Received I/O error ([object Object]) for streaming request - will retry

SDK version
6.4.3

Language version, developer tools
node v16.14.2

OS/platform
Docker node16 image

[kinyoklion]

Hello @Pipo93,

Thank you for raising this issue.

We will look into how we are getting an error without a status or a message. I would be hesitant to stringify it though.

Filed internally as 176346

Thanks,
Ryan

[kinyoklion]

Hey @Pipo93,

It looks like this will only happen when the underlying request either completes, or closes prematurely, but there is no error. In this case the event source raises an 'end' event, which doesn't have a message, and the node server doesn't handle that correctly. I will provide another update once we have released a fix.

Thanks,
Ryan

[praxxis]

We can reproduce this by connecting to an ld-relay implementation in streaming mode, when the relay has a maxClientConnectionTime set. It kills the connection every ~5 minutes, causing Received I/O error ([object Object]) for streaming request - will retry to be logged as a warning.

[kinyoklion]

This is fixed in @launchdarkly/node-server-sdk version 9.4.1.

• The js-eventsource has been updated to report a message in the case of an unexpected disconnect.
• The server has been updated to use the corresponding version.
• If there is no message a default message is now shown instead of logging the object.