ES2015 import fails with Rollup, no docs

I’m using Winston in an ES2015 project. I import Winston with import log from 'winston' and log with log.info(), log.debug(), etc. When I transpile and run with Babel it works just fine.

However if I use Rollup to resolve all the relative import paths and then the babel Rollup plugin to transpile (with the es2015-rollup plugin for Babel), the import of Winston fails. In particular, it imports the following object:

{ transports: 
   { console: 
      EventEmitter {
        domain: null,
        _events: {},
        _eventsCount: 0,
        _maxListeners: undefined,
        silent: false,
        raw: false,
        name: 'console',
        formatter: undefined,
        level: undefined,
        handleExceptions: false,
        exceptionsLevel: 'error',
        humanReadableUnhandledException: false,
        json: false,
        colorize: false,
        prettyPrint: false,
        timestamp: false,
        showLevel: true,
        label: null,
        logstash: false,
        depth: null,
        align: false,
        stderrLevels: [Object],
        eol: '\n',
        _onError: [Function: bound ] } },
  exceptionHandlers: {} }

This can be fixed by using import * as log from 'winston', but this is not at all obvious. I’m not sure what Rollup is doing in detail, but it looks like a great piece of ES2015 tooling, so Winston should work with it cleanly.

I would recommend adding a section to the Winston README on how to use it with ES2015, and perhaps add a caveat with respect to Rollup. Currently there is no guidance, and nothing on Google either.

[paulerickson]

Definitely still broken in 3.1.0.

If you use Node’s builtin ‘stream’ module instead of ‘readable-stream’ from NPM, you resolve the undefined / circular dependency thing, and if you get rid of the dynamic import crap in logform, then it works for me.

To put that in the hackiest possible terms…

find node_modules/{winston,winston-transport,logform} -type f -exec sed -i -e "s/require(.readable-stream.)/require('stream')/g" -e "s/require(.readable-stream\/writable.)/require('stream').Writable/g" -e "s/exposeFormat('\(\w*\)', '\(.*\)'/format.\1 = require('.\/\2.js'/g" -e "s/exposeFormat('\(\w*\)'/format.\1 = require('.\/\1.js'/g" {} +

[ipol2n]

This issue has been solved in 3.0.0