Transport closes before logs are shipped

[janianttonen]

Transport closes before logs are shipped

[JaniAnttonen]

Nice find. Might want to take a closer look at the events winston listens to. I'll come back at you, but you're welcome to submit a solution if you find one :)

[JaniAnttonen]

It is a bit weird though, if the logged event firing is the culprit. The index.js structure is based on https://github.com/winstonjs/winston/blob/bc6a363ec9164d03f266cab7c918d92208d2ec73/examples/custom-transport.js, that's why the logged event gets fired before the transport. Are you using batching or sending out logs as they come? Does changing that option change things?

[JaniAnttonen]

#51 might have fixed this?

[zabil]

Hi, We see this issue where the logs are not completely shipped.

For reference here is the setup.

  logger = winston.createLogger({
    level,
    transports: [
      new LokiTransport({
        host: lokiHost,
        batching: false,
        format: json(),
        onConnectionError: (err) => console.error(err),
      }),
    ]
  });

 export default logger;

Usage in lambda

import log from "logger";

export const handler = async (event: S3ObjectEvent) => {
  log.info("Received S3 Notification event");
  // And other log events
}

We have noticed that not all the log statements are being sent, especially the ones at the end. We think this happens because the handler shuts down after the response.

Version info

    "node_modules/winston-loki": {
      "version": "6.0.6",
      "resolved": "https://registry.npmjs.org/winston-loki/-/winston-loki-6.0.6.tgz",
      ...

[rlfrahm]

I'm encountering this issue as well. I'm using this for scripts run by ts-node, so my workaround has been to wait for 5 seconds at the end of the script before process.exit(0). I'm not sure what to do for an API endpoint for instance yet. I see there are some options to pass in to the LokiTransport constructor like timeout and gracefulShutdown, as well as flush() available from the class, but I've not tested a combo that solves this issue.