webpack-dev-middleware 不会将输出编译到文件夹中

Question

I'm using webpack-dev-middleware in my server to compile javascript like this:

if (development){                                                          
  app.use(webpackMiddleware(webpack({                                      
     // webpack options                                                   
     // webpackMiddleware takes a Compiler object as first parameter      
     // which is returned by webpack(...) without callback.               
    entry: {                                                               
      dashboard: path.join(__dirname, 'scripts/dashboard.jsx'),            
      tasks: path.join(__dirname, 'scripts/tasks.jsx')                     
    },                                                                     
       output: {                                                            
          path: __dirname + 'dist',                                        
          filename: '[name].bundle.js',                                    
          // no real path is required, just pass "/"                       
          // but it will work with other paths too.                        
      },                                                                   
      resolve: {                                                           
        extensions: ['', '.js', '.jsx']                                    
      },                                                                   
      module: {                                                            
        loaders: [                                                         
           { test: /\.jsx$/, loader: "jsx" }                            
      ]                                                                  
      }                                                                    
  }                                                                        
  ),                                                                       
  {                                                                        
    stats: {                                                               
     colors: true                                                         
    }                                                                      
  }));                                                                     
} 

Everything works fine in development, I can include the bundles in my views. But in production I cannot include them, because they are not build into 'dist'. This folder is always empty. What do I do wrong? Does somebody has an idea?

Best Regards Jan

Answer 1

webpack-dev-middleware doesn't output any file. If you want to output real files, you need to use the webpack command outside of express. You can put your webpack config into a seperate file, and refer to that with both your webpack command and require it in your express script to access it.

Answer 2

if you want to use the in-memory bundle, you can use the streamed file like this:

var express = require('express');
var app = express();
var webpack = require('webpack');
var path = require('path');

var compiler = webpack(require('./webpack.config.js'));

app.use(require('webpack-dev-middleware')(compiler, {
  noInfo: true,
  publicPath: '/'
}));

app.use('*', function (req, res, next) {
  var filename = path.join(compiler.outputPath,'index.html');
  compiler.outputFileSystem.readFile(filename, function(err, result){
    if (err) {
      return next(err);
    }
    res.set('content-type','text/html');
    res.send(result);
    res.end();
  });
});

app.listen(3000);

Answer 3

There is an available option in webpack-dev-middleware .

writeToFile can be a boolean or a function that receives the file path and outputs an boolean. See the documentation here

Here, I'm using a function so all the intermediate bundles don't get written to disk, only the whole bundle:

const webpack = require('webpack');
const webpackconfig = require('./webpack.config.js');
const webpackMiddleware = require("webpack-dev-middleware");

function shouldWrite(filePath) {
    if (path.basename(filePath) == 'bundle.js' || path.basename(filePath) == 'bundle.js.map') {
        return true
    }
    else {
        return false;
    }
}

const webpackCompiler = webpack(webpackconfig);
const wpmw = webpackMiddleware(webpackCompiler, {
        noInfo: true,
        publicPath: webpackConfig.output.publicPath,
        writeToDisk: shouldWrite
    });

//express
app.use(wpmw); // dev-middleware