[node.js] TypeScript getting error TS2304: cannot find name ' require'

I am trying to get my first TypeScript and DefinitelyTyped Node.js application up and running, and running into some errors.

I am getting the error "TS2304: Cannot find name 'require' " when I attempt to transpile a simple TypeScript Node.js page. I have read through several other occurrences of this error on Stack Overflow, and I do not think I have similar issues. I am running at the shell prompt the command:

tsc movie.server.model.ts.

The contents of this file are:

'use strict';

/// <reference path="typings/tsd.d.ts" />

/*    movie.server.model.ts - definition of movie schema */

var mongoose = require('mongoose'),
Schema = mongoose.Schema;

var foo = 'test';

The error is thrown on the var mongoose=require('mongoose') line.

The contents of the typings/tsd.d.ts file are:

/// <reference path="node/node.d.ts" />
/// <reference path="requirejs/require.d.ts" />

The .d.ts file references were placed in the appropriate folders and added to typings/tsd.d.ts by the commands:

tsd install node --save
tsd install require --save

The produced .js file seems to work fine, so I could ignore the error. But I would appreciate knowing why this error occurs and what I am doing wrong.

As approved answer didn't mention possibility to actually create your own typings file, and import it there, let me add it below.

Assuming you use npm as your package manager, you can:

npm i @types/node --save-dev

Then in your tsconfig file:

tsconfig.json

"include": ["typings.d.ts"],

Then create your typings file:

typings.d.ts

import 'node/globals'

Done, errors are gone, enjoy TypeScript :)

Just in addition to cgatian's answer, for TypeScript 1.x

If you are still seeing errors, please specifically provide index.d.ts in your compiler options.

"files": [
    "typings/index.d.ts"
]

I've yet another answer that builds upon all previous ones that describe npm install @types/node and including node in tsconfig.json / compilerOptions / types.

In my case, I have a base tsConfig.json and a separate one in the Angular application that extends this one:

{
    "extends": "../../tsconfig.json",
    "compilerOptions": {
        "outDir": "../out-tsc/app",
        "types": []
 },

My problem was the empty types in this tsconfi.app.json - it clobbers the one in the base configuration.

Electron + Angular 2/4 addition:

On top of adding the 'node' type to ts.config various files, what eventually worked for me was adding the next to the typings.d.ts file:

declare var window: Window;
interface Window {
  process: any;
  require: any;
}

Note that my case is developing with Electron + Angular 2/4. I needed the require on the window global.

Sometime missing "jasmine" from tsconfig.json may cause this error. (TypeScript 2.X)

So add

"types": [
  "node",
  "jasmine"
]

to your tsconfig.json file.

This answer relates to modern setups (TypeScript 2.x, Webpack > 2.x)

You don't need to install @types/node (which is all of Node.js types and is irrelevant for front-end code, actually complicating things such as setTimout different return values, etc..

You do need to install @types/webpack-env

npm i -D @types/webpack-env

which gives the runtime signatures that Webpack has (including require, require.ensure, etc.)

Also make sure that your tsconfig.json file has no set 'types' array -> which will make it pickup all type definitions in your node_modules/@types folder.

If you want to restrict search of types you can set the typeRoot property to node_modules/@types.

Instead of:

'use strict';

/// <reference path="typings/tsd.d.ts" />

Try:

/// <reference path="typings/tsd.d.ts" />

'use strict';

i.e. reference path first.

If you can compile code, but Visual Studio 2015 marks 'require' functions as errors with error text cannot find name 'require' or cannot resolve symbol 'require', update TypeScript for Visual Studio 2015 to the latest version (at the moment 2.1.5) and update ReSharper (if you use it) to at least version 2016.3.2.

I had this annoying problem for a while and couldn't find a solution, but I finally resolved it this way.

Just for reference, I am using Angular 7.1.4, TypeScript 3.1.6, and the only thing I need to do is to add this line in tsconfig.json:

    "types": ["node"], // within compilerOptions

You can

declare var require: any

Or, for more comprehensive support, use DefinitelyTyped's require.d.ts

Also, instead of var mongoose = require('mongoose'), you could try the following

import mongoose from 'mongoose' // or
import mongoose = require('mongoose')

I couldn't get the 'require' error to go away by using any of the tricks above.

But I found out that the issue was that my TypeScript tools for Visual Studio where an old version (1.8.6.0) and the latest version as of today is (2.0.6.0).

You can download the latest version of the tools from:

TypeScript for Visual Studio 2015

If you are facing this issue in a .ts file which is only there to provide you some constant values, then you can just

rename your .ts file to .js file

and the error will not come again.

import * as mongoose from 'mongoose'

Add the following in tsconfig.json:

"typeRoots": [ "../node_modules/@types" ]

1. Did you specify what module to use to transpile the code?
   tsc --target es5 --module commonjs script.ts
   You must do that to let the transpiler know that you're compiling NodeJS code. Docs.

2. You must install mongoose definitions as well
   tsd install mongoose --save

3. Do not use var to declare variables (unless necessary, which is a very rare case), use let instead. Learn more about that

I found the solution was to use the TSD command:

tsd install node --save

Which adds/updates the typings/tsd.d.ts file and that file contains all the type definitions that are required for a node application.

At the top of my file, I put a reference to the tsd.d.ts like this:

/// <reference path="../typings/tsd.d.ts" />

The require is defined like this as of January 2016:

declare var require: NodeRequire;

interface NodeModule {
    exports: any;
    require: NodeRequireFunction;
    id: string;
    filename: string;
    loaded: boolean;
    parent: any;
    children: any[];
}

For TypeScript 2.x, there are now two steps:

1. Install a package that defines require. For example:

   npm install @types/node --save-dev
   

2. Tell TypeScript to include it globally in tsconfig.json:

   {
       "compilerOptions": {
           "types": ["node"]
       }
   }
   

The second step is only important if you need access to globally available functions such as require. For most packages, you should just use the import package from 'package' pattern. There's no need to include every package in the tsconfig.json types array above.

I've been struggling from this issue as well. I believe that this works for all release candidates aka rc but I didn't test is though. For @angular rc.2 it works well.

1. Add core-js as npm dependency in package.json
2. run typings install core-js --save
3. remove all "es6-shim" occurances in your package.json. You don't need it anymore.

Cheers!

In my case, it was a super stupid problem, where the src/tsconfig.app.json was overriding the tsconfig.json setting.

So, I had this in tsconfig.json:

    "types": [
      "node"
    ]

And this one in src/tsconfig.app.json:

    "types": []

I hope someone finds this helpful, as this error was causing me gray hairs.

For me it is resolved by adding types to the angular compiler options.

"angularCompilerOptions": {
"fullTemplateTypeCheck": true,
"strictInjectionParameters": true,
"types": [ "node" ]
}

I took Peter Varga's answer to add declare var require: any; and made it into a generic solution that works for all .ts files generically by using the preprocess-loader:

1. install preprocessor-loader:

   npm install preprocessor-loader
   

2. add the loader to your webpack.config.js (I'm using ts-loader for processing TypeScript sources):

    module: {
        loaders: [{
            test: /\.tsx?$/,
            loader: 'ts-loader!preprocessor?file&config=preprocess-ts.json'
        }]
    }

3. Add the configuration that will add the workaround to every source:

{
    "line": false,
    "file": true,
    "callbacks": [{
        "fileName": "all",
        "scope": "source",
        "callback": "(function shimRequire(source, fileName) { return 'declare var require: any;' + source; })"
    }]
}

You can add the more robust require.d.ts the same way, but declare var require: any; was sufficient in my situation.

Note, there's a bug in preprocessor 1.0.5, which cuts off the last line, so just make sure you have an extra line space return at the end and you'll be fine.

Make sure you have installed npm i @types/node