在 Angular 4 中使用节点模块（网站刮板）使用失败

Posted 2023-03-07

【中文标题】在 Angular 4 中使用节点模块（网站刮板）使用失败

【英文标题】：Using node_module (website scraper) in Angular 4 failes on usage

【发布时间】：2018-04-19 11:27:47

【问题描述】：

目前我正在尝试将 node_module “网站抓取工具” [1] 添加到我的 Angular 4 项目中。 我通过“npm install website-scraper –save”下载并安装模块。 在我的组件中，我通过“import * as Scraper from 'website-scraper'”导入模块。

到目前为止，一切都按预期编译。 如果我现在只是在我的组件的某处添加“console.log(Scraper)”，我会收到警告 [3] 并且我的浏览器会抛出错误 [2]

有人可以告诉我，出了什么问题？我使用节点 8.9.0 和 npm 5.5.1。无论如何，我尝试了多个更进一步（旧）版本的 node 和 npm 导致相同的行为。任何帮助表示赞赏。提前致谢。

[1] https://www.npmjs.com/package/website-scraper

[2] graceful-fs.js:166 Uncaught TypeError: Cannot read property 'prototype' of undefined
    at patch (graceful-fs.js:166)
    at Object.eval (graceful-fs.js:27)
    at eval (graceful-fs.js:262)
    at Object.../../../../graceful-fs/graceful-fs.js (vendor.bundle.js:884)
    at __webpack_require__ (inline.bundle.js:55)
    at eval (index.js:4)
    at Object.../../../../fs-extra/lib/fs/index.js (vendor.bundle.js:726)
    at __webpack_require__ (inline.bundle.js:55)
    at eval (index.js:8)
    at Object.../../../../fs-extra/lib/index.js (vendor.bundle.js:734)
    at __webpack_require__ (inline.bundle.js:55)
    at Object.eval (index.js:6)
    at eval (index.js:69)
    at Object.../../../../website-scraper/lib/resource-saver/index.js (vendor.bundle.js:3110)
    at __webpack_require__ (inline.bundle.js:55)
    at eval (scraper.js:16) 


[3]: WARNING in ./node_modules/har-validator/node_modules/ajv/lib/async.js
119:15-28 Critical dependency: the request of a dependency is an expression
    at CommonJsRequireContextDependency.getWarnings (C:\Users\XY\XYZ\MyProject\node_modules\webpack\lib\dependencies\ContextDependency.js:39:18)
    at Compilation.reportDependencyErrorsAndWarnings (C:\Users\XY\XYZ\MyProject\node_modules\webpack\lib\Compilation.js:703:24)
    at Compilation.finish (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:561:9)
    at applyPluginsParallel.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compiler.js:506:17)
    at C:\Users\MyUser\MyProject\A1\node_modules\tapable\lib\Tapable.js:289:11
    at _addModuleChain (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:507:11)
    at processModuleDependencies.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:477:14)
    at _combinedTickCallback (internal/process/next_tick.js:67:7)
    at process._tickCallback (internal/process/next_tick.js:98:9)
 @ ./node_modules/har-validator/node_modules/ajv/lib/async.js
 @ ./node_modules/har-validator/node_modules/ajv/lib/ajv.js
 @ ./node_modules/har-validator/lib/node4/promise.js
 @ ./node_modules/request/lib/har.js
 @ ./node_modules/request/request.js
 @ ./node_modules/request/index.js
 @ ./node_modules/website-scraper/lib/request.js
 @ ./node_modules/website-scraper/lib/scraper.js
 @ ./src/app/mytest/mytest.component.ts
 @ ./src/app/app.module.ts
 @ ./src/main.ts
 @ multi webpack-dev-server/client?http://0.0.0.0:0 ./src/main.ts

WARNING in ./node_modules/har-validator/node_modules/ajv/lib/compile/index.js
13:21-34 Critical dependency: the request of a dependency is an expression
    at CommonJsRequireContextDependency.getWarnings (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\dependencies\ContextDependency.js:39:18)
    at Compilation.reportDependencyErrorsAndWarnings (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:703:24)
    at Compilation.finish (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:561:9)
    at applyPluginsParallel.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compiler.js:506:17)
    at C:\Users\MyUser\MyProject\A1\node_modules\tapable\lib\Tapable.js:289:11
    at _addModuleChain (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:507:11)
    at processModuleDependencies.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:477:14)
    at _combinedTickCallback (internal/process/next_tick.js:67:7)
    at process._tickCallback (internal/process/next_tick.js:98:9)
 @ ./node_modules/har-validator/node_modules/ajv/lib/compile/index.js
 @ ./node_modules/har-validator/node_modules/ajv/lib/ajv.js
 @ ./node_modules/har-validator/lib/node4/promise.js
 @ ./node_modules/request/lib/har.js
 @ ./node_modules/request/request.js
 @ ./node_modules/request/index.js
 @ ./node_modules/website-scraper/lib/request.js
 @ ./node_modules/website-scraper/lib/scraper.js
 @ ./src/app/mytest/mytest.component.ts
 @ ./src/app/app.module.ts
 @ ./src/main.ts
 @ multi webpack-dev-server/client?http://0.0.0.0:0 ./src/main.ts

WARNING in ./node_modules/har-validator/node_modules/ajv/lib/async.js
96:20-33 Critical dependency: the request of a dependency is an expression
    at CommonJsRequireContextDependency.getWarnings (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\dependencies\ContextDependency.js:39:18)
    at Compilation.reportDependencyErrorsAndWarnings (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:703:24)
    at Compilation.finish (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:561:9)
    at applyPluginsParallel.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compiler.js:506:17)
    at C:\Users\MyUser\MyProject\A1\node_modules\tapable\lib\Tapable.js:289:11
    at _addModuleChain (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:507:11)
    at processModuleDependencies.err (C:\Users\MyUser\MyProject\A1\node_modules\webpack\lib\Compilation.js:477:14)
    at _combinedTickCallback (internal/process/next_tick.js:67:7)
    at process._tickCallback (internal/process/next_tick.js:98:9)
 @ ./node_modules/har-validator/node_modules/ajv/lib/async.js
 @ ./node_modules/har-validator/node_modules/ajv/lib/ajv.js
 @ ./node_modules/har-validator/lib/node4/promise.js
 @ ./node_modules/request/lib/har.js
 @ ./node_modules/request/request.js
 @ ./node_modules/request/index.js
 @ ./node_modules/website-scraper/lib/request.js
 @ ./node_modules/website-scraper/lib/scraper.js
 @ ./src/app/mytest/mytest.component.ts
 @ ./src/app/app.module.ts
 @ ./src/main.ts
 @ multi webpack-dev-server/client?http://0.0.0.0:0 ./src/main.ts

【问题讨论】：

你也应该安装npmjs.com/package/@types/website-scraper。

您好，感谢您的提及。我已经这样做了，不幸的是事情没有改变（代码自动完成除外）。

【参考方案1】：

您不能将website-scraper 直接添加到您的 Angular 项目中，因为它仅用于 nodejs 的服务器端使用。

我可以建议在服务器端使用它并将结果返回给客户端。 这是一个如何在服务器上使用 website-scraper 和 nodejs 并在客户端使用 express 和 angular 1 的示例：https://github.com/website-scraper/demo

【讨论】：

谢谢，我真的把这个弄糊涂了。我真的很高兴，你清除了这个话题。