Hi guys! I do some tests:

I create a repository with different transport classes to test the issue.

• asyncLogger is an implementation extending from winston-transport class. The transport is executed on the file notWorking.js using winston logger.
• asyncStream is an implementation extending from stream.Writable class. The transport is executed on the file working.js. The stream is used directly without winston.
• asyncStreamWinston is an implementation extending from stream.Writable class. The transport is executed on the file someChunksAreMissing.js. The stream is used as a transport for winston logger.

If you check each transport class, you will see that the implementation is almost the same.

Extending from winston-transport class only works if the buffer is less than the highWaterMark value. Otherwise, the program will crash. To make it work, I can remove the setImmediate function and call the callback directly. Extending from stream.Writable class and using the same options works as expected even with a callback called inside the setImmediate function. Extending from stream.Writable class and using the same options but as a transport for winston logger, the last chunk is missing. The difference with the first scenario is that I do can call the callback inside the setImmediate function but the last chunk is missing.

Install

nvm use v18
npm ci

Run scenarios

npm run start:working
npm run start:not-working
npm run start:missing-logs