当在Angular中的DI中使用从库导入的工厂函数时,AOT编译失败

Question

我有一个Angular 6.1应用程序,它导入一些外部模块.

当我在AOT模式下编译应用程序时:

$ ng build --aot

我收到这个错误:

ERROR in ./src/app.component.ngfactory.js
Module not found: Error: Can't resolve '/home/user/project/node_modules/@acme/library/src/library/library' in '/home/user/project/src/app'
resolve '/home/user/project/node_modules/@acme/library/src/library/library' in '/home/user/project/src/app'
  using description file: /home/user/project/package.json (relative path: ./src/app)
    Field 'browser' doesn't contain a valid alias configuration
    using description file: /home/user/project/node_modules/@acme/library/package.json (relative path: ./src/library/library)
      no extension
        Field 'browser' doesn't contain a valid alias configuration
        /home/user/project/node_modules/@acme/library/src/library/library doesn't exist
      .ts
        Field 'browser' doesn't contain a valid alias configuration
        /home/user/project/node_modules/@acme/library/src/library/library.ts doesn't exist
      .tsx
        Field 'browser' doesn't contain a valid alias configuration
        /home/user/project/node_modules/@acme/library/src/library/library.tsx doesn't exist
      .mjs
        Field 'browser' doesn't contain a valid alias configuration
        /home/user/project/node_modules/@acme/library/src/library/library.mjs doesn't exist
      .js
        Field 'browser' doesn't contain a valid alias configuration
        /home/user/project/node_modules/@acme/library/src/library/library.js doesn't exist
      as directory
        /home/user/project/node_modules/@acme/library/src/library/library doesn't exist
[/home/user/project/node_modules/@acme/library/src/library/library]
[/home/user/project/node_modules/@acme/library/src/library/library.ts]
[/home/user/project/node_modules/@acme/library/src/library/library.tsx]
[/home/user/project/node_modules/@acme/library/src/library/library.mjs]
[/home/user/project/node_modules/@acme/library/src/library/library.js]
 @ ./src/app.component.ngfactory.js 12:0-92 30:102-122 30:186-206 33:204-224 33:289-309 36:204-224 36:289-309 45:102-122 45:187-207 51:102-122 51:187-207 120:102-122 120:187-207
 @ ./src/app/app.module.ngfactory.js
 @ ./src/main.ts
 @ multi ./src/main.ts

该路径node_modules/@acme/library/src/library/library指向一个library.d.ts文件,该文件存在于模块目录中.

如果我从外部包中完全删除键入信息,则应用程序将编译并正常工作.此外,如果我手动将所有打字合并到一个index.d.ts文件中,编译就完成了.

我认为编译器如何解析类型定义文件有问题,看起来它不是.d.ts因为某些原因而没有查找带扩展名的文件.

---

更新1

外部模块@acme/library也由我开发和预编译.它是一个简单的TypeScript库,包含一些导出的类和函数.它没有使用像Angular那样的装饰和东西.

它package.json有以下字段:

"es2015": "index.es2015.js",
"main": "index.min.js",
"module": "index.es5.js",
"typings": "index.d.ts",

所有提到的文件都存在于包的根目录中.

---

更新2

经过进一步调查,看起来问题是由依赖注入引起的.请参阅下面的示例.

我正在使用自定义工厂提供程序,以便为Library组件的构造函数注入一个实例.

该libraryFactory函数从外部模块导入,如下所示:

export function libraryFactory(): Library {
  const dep1 = new Dep1();
  const dep2 = new Dep2();
  return new Library(dep1, dep2);
}

失败的例子

import {Component} from '@angular/core';

import {Library, libraryFactory} from '@acme/library';


@Component({
  selector: 'app-foo',
  templateUrl: './foo.component.html',
  providers: [
    {
      provide: Library,
      useFactory: libraryFactory
    }
  ]
})
export class FooComponent {

  constructor(public library: Library) {
  }

}

工作实例

但是,如果我摆脱DI它编译并正常工作:

import {Component} from '@angular/core';

import {Library, libraryFactory} from '@acme/library';


@Component({
  selector: 'app-foo',
  templateUrl: './foo.component.html'
})
export class FooComponent {

  public library: Library;


  constructor() {
    this.library = libraryFactory();
  }

}

---

什么可能导致这个问题？

如果需要,我会很乐意提供更具体的信息.

Answer 1

Angular 不知道要向您的 Library 类注入什么，因为Dep1在Dep2使用useFactory. 所以你可以简单地改变useFactory你useValue失败的例子，那么它一定没问题。

或者

如果你想使用工厂作为库实例，你必须在库之前注入Dep1和Dep2到提供者。如果Dep1并且Dep2本身没有依赖关系，那么它一定可以工作。如果它们也有依赖项，您也必须注入它们。

import {Component} from '@angular/core';

import {Library, Dep1, Dep2} from '@acme/library';

const dep1instance = new Dep1();
const dep2instance = new Dep2();

@Component({
  selector: 'app-foo',
  templateUrl: './foo.component.html',
  providers: [
    {
      provide: Dep1,
      useValue: dep1instance
    },
    {
      provide: Dep2,
      useValue: dep2instance
    },
    {
      provide: Library,
      useFactory: (dep1: Dep1, dep2: Dep2) => new Library(dep1, dep2),
      deps:[Dep1,Dep2]
    }
  ]
})
export class FooComponent {

  constructor(public library: Library) {
  }

}

或者

您可以使用Injectible装饰器对您的库进行分支，以实现角度 DI 兼容性。IMO 简单、可维护且有用的选择。