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webpackkoa

I get a webpack warning Critical dependency: the request of a dependency is an expression when use koa

When I start webpack for bundling my react application using koa with server side rendering I get a warning

WARNING in /app/node_modules/any-promise/register.js 24:14-37
[1] Critical dependency: the request of a dependency is an expression
[1]  @ /app/node_modules/any-promise/index.js
[1]  @ /app/node_modules/koa-compose/index.js
[1]  @ /app/node_modules/koa-convert/index.js
[1]  @ /app/node_modules/koa/lib/application.js
[1]  @ ./server/index.ts

Should I worry?

Solution

  • Well, I answered this question a few hours ago in any-promise Github repository.

    So I just copy the answer here:

    It happened because register.js has a dynamic import on 24 lines:

    var lib = require(implementation)

    It means webpack can't resolve the require statically and imports entire package

    You can read this part of webpack docs: https://webpack.js.org/guides/dependency-management/#require-with-expression

    It can be solved using ContextReplacementPlugin, for example, you can add "fake" config in your webpack to suppress this warning

    plugins: [
    new ContextReplacementPlugin(/any-promise/)
]

    And I think you don't have to worry because webpack requires "unnecessary" packages only into your server app.

    You also can keep track of this issue: https://github.com/kevinbeaty/any-promise/issues/31