Typescript import issues

[Tom Feldmann]

What's the preferred way of importing this module? So far I'm not able to import it so that I can use the koaSwagger function and get typings. I've tried:

import * as koaSwagger from 'koa2-swagger-ui';
results in:
TS2349: Cannot invoke an expression whose type lacks a call signature.

---

import koaSwagger from 'koa2-swagger-ui';
I get typings but I get the runtime error:
TypeError: koa2_swagger_ui_1.default is not a function

---

const koaSwagger = require('koa2-swagger-ui');
Works but I get no typings.

---

import { koaSwagger } from 'koa2-swagger-ui';
Cannot do this because the module has no export member named koaSwagger.

[Scott Cooper]

import koaSwagger from 'koa2-swagger-ui';

is working for me. maybe make sure you have "esModuleInterop": true, in your tsconfig.

here's what i'm using

{
  "compileOnSave": false,
  "compilerOptions": {
    "moduleResolution": "node",
    "lib": ["es2018"],
    "target": "es2017",
    "module": "commonjs",
    "esModuleInterop": true,
    "strict": true,
    "noImplicitAny": false,
    "noUnusedLocals": true,
    "declaration": true,
    "sourceMap": true,
    "inlineSources": true,
    "outDir": "dist"
  },
  "include": ["src/index.ts"]
}

[Tom Feldmann]

Thanks Scott!
Adding "esModuleInterop": true worked but I had to update a bunch of other imports to use that style. Sounds like a discussion on requiring esModuleInterop could end in a holy war so I'll just take my win and run.

Thanks again!

[Scott Cooper]

It’s probably because I tried to keep backwards comparability with the previous nodejs version. Oh well

[Dan Greene]

Okay @nodehack (and others), here's a workaround that allows you to include the library

• saves you from having to turning on esModuleInterop (which is great since that messes up every other import)
• it also gets you the types

import { KoaSwaggerUiOptions } from 'koa2-swagger-ui';
type koa2SwaggerUiFunc = (config: Partial<KoaSwaggerUiOptions>) => Koa.Middleware
// tslint:disable-next-line: no-var-requires // We actually have to use require for koa2-swagger-ui
const koaSwagger = require('koa2-swagger-ui') as koa2SwaggerUiFunc;