Webpack Error: Can't resolve 'async/forEach'

my environment:

• winston 3.0.0-rc5
• node 6.7.0
• OS Linux
• ES6/7 with webpack+babel

What is the problem?

When using webpack to bundle my server code I get an error while bundling when using winston:

ERROR in ../node_modules/winston/lib/winston/exception-handler.js
Module not found: Error: Can't resolve 'async/forEach' in '~/myProject/node_modules/winston/lib/winston'
resolve 'async/forEach' in '~/myProject/node_modules/winston/lib/winston'
    Parsed request is a module
    using description file: ~/myProject/node_modules/winston/package.json (relative path: ./lib/winston)
    after using description file: ~/myProject/node_modules/winston/package.json (relative path: ./lib/winston)
    resolve as module
        looking for modules in ~/myProject/node_modules
        using description file: ~/myProject/package.json (relative path: ./node_modules)
        after using description file: ~/myProject/package.json (relative path: ./node_modules)
            using description file: ~/myProject/node_modules/async/package.json (relative path: ./forEach)
            no extension
                ~/myProject/node_modules/async/forEach doesn't exist
            .js
                ~/myProject/node_modules/async/forEach.js doesn't exist
            .json
                ~/myProject/node_modules/async/forEach.json doesn't exist
            as directory
                ~/myProject/node_modules/async/forEach doesn't exist

my code:

import winston from "winston";
[...]

opening a node console and using CommonJS require does not lead to any error, so I suppose it’s a combination of winston and webpack.

my webpack config looks like this:

const ServerConfig = {
    context: distPath,
    entry: ["babel-polyfill", path.resolve(srcPath, "src", "server")],
    output: {
        path: distPath,
        filename: "server.bundle.js"
    },
    profile: true,
    stats: outputOptions,
    module: {
        loaders: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                loaders: ["happypack/loader?id=js"]
            }
        ]
    },
    target: "node",
    plugins: [
        new webpack.DefinePlugin({ "global.GENTLY": false }),
        new CopyWebpackPlugin([
            {
                context: srcPath,
                from: "config",
                to: "config"
            }
        ]),
        new HappyPack({
            id: "js",
            loaders: [
                {
                    loader: "babel-loader",
                    options: {
                        cacheDirectory: true
                    }
                }
            ]
        }),
        /**
         * The settings below fix warnings due to require path handling. Switching context to packages
         * base folder solves some warnings. Colors package dynamically requires themes, which we'll
         * assign the default located at the packages themes folder.
         */
        new webpack.ContextReplacementPlugin(/colors[\/\\]lib$/, "../themes/generic-logging.js")
    ],
    resolve: {
        modules: [path.resolve(__dirname, "node_modules")]
    },
    externals: nodeModules
};

What do you expect to happen instead?

Well …

Other information

It looks like winston is trying to require something, that is not part of the async package.

[nikita-malyschkin-work]

removing the resolve statement in the webpack config solved my issue, thanks! 👍

I still wonder why this wasn’t an issue with all my other modules.

PS. Adding "node_modules" to the array fixed the problem as well.

resolve: {
    modules: [path.resolve(__dirname, "node_modules"), "node_modules"]
}

[hhaseli]

This worked for me:

npm uninstall async
npm install -g async
npm link async