Webpack--- optimization_ cache

One 、babel cache

{
    test: //,
    loader: 'babel-loader',
    options: {
        //  The second build , Use cache content 
        cacheDirectory: true
    }
}

Two 、 Resource cache （ Production optimization ）

hash： Every time webpack Unique... Will be generated at build time hash
chunkhash： The same chunk,hash equally 
contenthash： Generate according to the contents of the file hash, Of different files hash It must be different 

 Method ： After packing js、css Add... To the filename contenthash