当我将导入从 lodash 替换为 lodash-es 时,Angular Universal服务器中断。但是当我运行ng serve
时,事情就好了。我想使用lodash-es所以我可以在我的Angular SPA中挑选lodash函数并缩小包大小。
我采取的步骤:npm卸载 lodash ,npm安装了 lodash-es ,并替换了我的导入:
来自:import { find as _find } from "lodash";
收件人:import { find as _find } from "lodash-es"
;
这是我收到的服务器错误:
/usr/src/app/node_modules/lodash-es/lodash.js:10
export { default as add } from './add.js';
^^^^^^
SyntaxError: Unexpected token export
at createScript (vm.js:80:10)
at Object.runInThisContext (vm.js:139:10)
at Module._compile (module.js:599:28)
at Object.Module._extensions..js (module.js:646:10)
at Module.load (module.js:554:32)
at tryModuleLoad (module.js:497:12)
at Function.Module._load (module.js:489:3)
at Module.require (module.js:579:17)
at require (internal/module.js:11:18)
at Object.<anonymous> (/usr/src/app/dist/server.js:246:18)
server.ts
import "zone.js/dist/zone-node";
import "reflect-metadata";
import { renderModuleFactory } from "@angular/platform-server";
import { enableProdMode } from "@angular/core";
import * as express from "express";
import * as minifyHTML from "express-minify-html";
import { join } from "path";
import { readFileSync } from "fs";
// Faster server renders w/ Prod mode (dev mode never needed)
enableProdMode();
// Express server
const app = express();
const PORT = process.env.PORT || 4000;
const DIST_FOLDER = join(process.cwd(), "dist");
// Our index.html we'll use as our template
const template = readFileSync(
join(DIST_FOLDER, "browser", "index.html")
).toString();
// * NOTE :: leave this as require() since this file is built Dynamically from webpack
const {
AppServerModuleNgFactory,
LAZY_MODULE_MAP
} = require("./dist/server/main.bundle");
// Express Engine
import { ngExpressEngine } from "@nguniversal/express-engine";
// Import module map for lazy loading
import { provideModuleMap } from "@nguniversal/module-map-ngfactory-loader";
app.use(
minifyHTML({
override: true,
exception_url: false,
htmlMinifier: {
removeComments: true,
collapseWhitespace: true,
collapseBooleanAttributes: true,
removeAttributeQuotes: true,
removeEmptyAttributes: true,
minifyJS: true,
minifyCSS: true
}
})
);
// Our Universal express-engine (found @ https://github.com/angular/universal/tree/master/modules/express-engine)
app.engine(
"html",
ngExpressEngine({
bootstrap: AppServerModuleNgFactory
})
);
app.set("view engine", "html");
app.set("views", join(DIST_FOLDER, "browser"));
/* - Example Express Rest API endpoints -
app.get('/api/**', (req, res) => { });
*/
// Server static files from /browser
app.get(
"*.*",
express.static(join(DIST_FOLDER, "browser"), {
maxAge: "1y"
})
);
// ALl regular routes use the Universal engine
app.get("*", (req, res) => {
res.render("index", { req });
});
// Start up the Node server
app.listen(PORT, () => {
console.log(`Node Express server listening on http://localhost:${PORT}`);
});
这是 webpack.server.config.js (可能相关吗?):
const path = require("path");
const webpack = require("webpack");
const nodeExternals = require("webpack-node-externals");
module.exports = {
entry: { server: "./server.ts" },
resolve: { extensions: [".ts", ".js"] },
target: "node",
externals: [nodeExternals()],
output: {
path: path.join(__dirname, "dist"),
filename: "[name].js"
},
module: {
rules: [{ test: /\.ts$/, loader: "ts-loader" }]
},
plugins: [
new webpack.DefinePlugin({
window: undefined,
document: undefined
}),
new webpack.ContextReplacementPlugin(
/(.+)?angular(\\|\/)core(.+)?/,
path.join(__dirname, "src"), // location of your src
{} // a map of your routes
),
new webpack.ContextReplacementPlugin(
/(.+)?express(\\|\/)(.+)?/,
path.join(__dirname, "src")
)
]
};
答案 0 :(得分:4)
解决方案是将lodash-es
列入白名单,正如大卫在对原始问题的评论中所建议的那样。具体来说,现在 webpack.server.config.js 如下所示:
...
externals: [
nodeExternals({
whitelist: [/^lodash-es/]
})
],
...
答案 1 :(得分:-1)
Angular 2+是打字稿..所以你需要使用下面的命令从npm安装@ types / lodash
npm install --save @types/lodash
然后你需要在组件中导入它:
import * as lodash from 'lodash';
你可以使用像
这样的lodashlodash.find() etc...