The declaration file for the 'express' module could not be located

Whenever I run my code to search for a request and response from an express server, I encounter an issue where it cannot find declarations for the 'express' module. The error message transitions from

Could not find a declaration file for module 'express'.
to
SyntaxError: Cannot use import statement outside a module

I attempted to use

const express = require('express')
. Then, I tried installing the types via npm. Now, I'm contemplating whether I need to create my own type definitions for my server.

import express, {request, response} from 'express'; 

const dictionary = {
    "apple": "A round fruit with red or green skin and a white flesh.",
    "banana": "A long curved fruit which grows in clusters and has soft pulpy flesh.",
    "orange": "A spherical fruit with a tough bright reddish-yellow rind.",
  };
  
  const app = express();
  app.use(express.json());
  
  // Define an API endpoint to get a definition for a word
  app.get('/:dictionary', function (req: request, res: response) {
    console.log(req.params[dictionary]);
    res.send();
});
 

app.listen(3000, () => {
  console.log("Server listening on port 3000");
});

This represents my current code snippet.

Answer №1

It appears that you are utilizing es6 import statements to bring in express, however, you are not implementing a module system. To rectify this issue within the tsconfig.json file, adjust the module value to commonjs.

tsconfig.json

"module": "commonjs",
"esModuleInterop": true

Subsequently, proceed to install types

npm install @types/node @types/express --dev

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