taro1.3.4版本 config index配置

 dev.js
    // NOTE H5 端使用 devServer 实现跨域，需要修改 package.json 的运行命令，加入环境变量
    const isH5 = process.env.CLIENT_ENV === 'h5'
    const HOST = '"https://min"'
    const HOST_M = '"https://"'
    
    module.exports = {
        env: {
         NODE_ENV: '"development"'
        },
        defineConstants: {
            HOST: isH5 ? '"/api"' : HOST,
            HOST_M: isH5 ? '"/api-m"' : HOST_M
        },
        weapp: {},
        h5: {
            devServer: {
                proxy: {
                    '/api/': {
                        target: JSON.parse(HOST),
                        pathRewrite: {
                        '^/api/': '/'
                        },
                        changeOrigin: true
                    },
                    '/api-m/': {
                        target: JSON.parse(HOST_M),
                        pathRewrite: {
                        '^/api-m/': '/'
                        },
                        changeOrigin: true
                    }
                }
            }
        }
    }
   <hr>
    prod.js
    const isH5 = process.env.CLIENT_ENV === 'h5'
    
    const HOST = '"https://mi"'
    const HOST_M = '"https://m"'
    
    // XXX 搭了个 proxy 用于演示 prod 环境的 H5
    const HOST_H5 = '"http://"'
    const HOST_M_H5 = '"http://"'
    
    module.exports = {
        env: {
            NODE_ENV: '"production"'
        },
        defineConstants: {
            HOST: isH5 ? HOST_H5 : HOST,
            HOST_M: isH5 ? HOST_M_H5 : HOST_M
        },
        weapp: {},
        h5: {
            publicPath: '/taro-yanxuan'
        }
    }
     
    ******************
    index.js:
    const path = require('path')
    
    // NOTE 在 sass 中通过别名（@ 或 ~）引用需要指定路径
    const sassImporter = function(url) {
        if (url[0] === '~' && url[1] !== '/') {
        return {
        file: path.resolve(__dirname, '..', 'node_modules', url.substr(1))
        }
    }
    
    const reg = /^@styles/(.*)/
        return {
            file: reg.test(url) ? path.resolve(__dirname, '..', 'src/styles', url.match(reg)[1]) : url
        }
    }
    
    const config = {
        projectName: 'taro-demo',
        date: '2019-12-1',
        designWidth: 750,
        deviceRatio: {
            '640': 2.34 / 2,
            '750': 1,
            '828': 1.81 / 2
        },
        sourceRoot: 'src',
        outputRoot: 'dist',
        plugins: {
            babel: {
                sourceMap: true,
                presets: [
                    ['env', {
                    modules: false
                    }]
                ],
                plugins: [
                    'transform-decorators-legacy',
                    'transform-class-properties',
                    'transform-object-rest-spread'
                ]
            },
            sass: {
                importer: sassImporter
            }
        },
        defineConstants: {
        },
        alias: {
            '@actions': path.resolve(__dirname, '..', 'src/actions'),
            '@assets': path.resolve(__dirname, '..', 'src/assets'),
            '@components': path.resolve(__dirname, '..', 'src/components'),
            '@constants': path.resolve(__dirname, '..', 'src/constants'),
            '@reducers': path.resolve(__dirname, '..', 'src/reducers'),
            '@styles': path.resolve(__dirname, '..', 'src/styles'),
            '@utils': path.resolve(__dirname, '..', 'src/utils')
        },
        copy: {
            patterns: [
            ],
            options: {
            }
        },
        weapp: {
            module: {
                postcss: {
                    autoprefixer: {
                        enable: true,
                        config: {
                        browsers: [
                            'last 3 versions',
                            'Android >= 4.1',
                            'ios >= 8'
                            ]
                        }
                    },
                    pxtransform: {
                        enable: true,
                        config: {
                        
                        }
                    },
                    url: {
                        enable: true,
                        config: {
                        limit: 10240 // 设定转换尺寸上限
                        }
                    },
                    cssModules: {
                        enable: false, // 默认为 false，如需使用 css modules 功能，则设为 true
                        config: {
                        namingPattern: 'module', // 转换模式，取值为 global/module
                        generateScopedName: '[name]__[local]___[hash:base64:5]'
                        }
                    }
                }
            }
        },
    h5: {
        // NOTE H5 打包静态资源时带 hash 值，方便缓存、版本管理
        publicPath: '/',
        staticDirectory: 'static',
        output: {
            filename: 'js/[name].[hash].js',
            chunkFilename: 'js/[name].[chunkhash].js'
        },
        imageUrlLoaderOption: {
            limit: 5000,
            name: 'static/images/[name].[hash].[ext]'
        },
        miniCssExtractPluginOption: {
            filename: 'css/[name].[hash].css',
            chunkFilename: 'css/[name].[chunkhash].css',
        },
        module: {
            postcss: {
                autoprefixer: {
                    enable: true,
                    config: {
                        browsers: [
                            'last 3 versions',
                            'Android >= 4.1',
                            'ios >= 8'
                        ]
                    }
                },
                cssModules: {
                    enable: false, // 默认为 false，如需使用 css modules 功能，则设为 true
                    config: {
                        namingPattern: 'module', // 转换模式，取值为 global/module
                        generateScopedName: '[name]__[local]___[hash:base64:5]'
                    }
               }
            }
        },
            sassLoaderOption: {
                importer: sassImporter
            }
        },
        rn: {
            appJson: {
                // NOTE taro-native-shell 中默认用的是 taroDemo
                name: 'taroDemo'
            }
        }
    }
    
    module.exports = function (merge) {
        if (process.env.NODE_ENV === 'development') {
        return merge({}, config, require('./dev'))
        }
        return merge({}, config, require('./prod'))
    }