Typescript: Require context of webpack missing property 'default' on type 'unkown'

Question

I'm using the context module API to include some files in my project.

On a value that I extract from the values property typescript is giving me the error: TS2339: Property 'default' does not exist on type 'unknown'.

How can I make this (strongly) typed?

const blogPosts = ((context): Data[] => {
    const keys = context.keys();
    const values = keys.map(context);

    console.log('values: ', values);
    // logs: (3) [Module, Module, Module]
    // 0: Module { default: "---↵title: "A blog title"↵author: John↵date:… etc", __esModule: true, Symbol(Symbol.toStringTag): "Module"}
    // 1: Module { default: "---↵title: "Another blog title"↵author: John↵date:… etc", __esModule: true, Symbol(Symbol.toStringTag): "Module"}
    // 2: Module { default: "---↵title: "Yet another blog title"↵author: John↵date:… etc", __esModule: true, Symbol(Symbol.toStringTag): "Module"}

    const data: Data[] = keys.map((key, index) => {
      const value = values[index];

      // TS2339: Property 'default' does not exist on type 'unknown'
      return matter(value.default) as DocumentFrontMatter;
    });

    return data;
  })(require.context('../posts', true, /\.md$/));

Edit: Removed the next part. Don't think it's in webpack-env. In @types/webpack and @types/webpack-env no notion of a 'default' is mentioned.

~~Note: I have added @types/webpack-env to my projects dependencies, and used it in the tsconfig.json (source):~~

"types": [
  "node",
  "webpack-env"
]

score 2 · Answer 1 · answered Mar 09 '20 at 05:51

As I was working on the code I circumvented this issue. I happened to have to use the same function again and did a re-write which removed the need for the default key.

Note the __WebpackModuleApi.RequireContext.

function importAll(webpackContext: __WebpackModuleApi.RequireContext): Data[] {
  return webpackContext.keys().map((fileUrl) => {
    const body = webpackContext(fileUrl);

    const slug: string = fileUrl;
    const document: DocumentFrontMatter = matter(body.default) as DocumentFrontMatter;

    return {
      slug,
      document,
    };
  });
}

// ...

const posts = importAll(require.context('../posts', true, /\.md$/));
const events = importAll(require.context('../events', true, /\.md$/));

Typescript: Require context of webpack missing property 'default' on type 'unkown'

1 Answers1