How to import JSON in node

With node >=18.0.0 or deno

Use an import with assert inside the import

app.js

import object from "./x.json" assert { type: "json" };
console.log(object);

x.json

{
    "key": "value"
}

node app.js

or with deno

deno run app.js

With node >=17.3.0

Use the cli flag --experimental-json-modules.

node --experimental-json-modules app.js

With older version than 17.3.0

Another way is to use a top level await and open the file as text and use JSON.parse

app.js (old)

import fsPromises from "node:fs/promises";

const jsonString = await fsPromises.readFile(`./x.json`, `utf-8`);
const object  = JSON.parse(jsonString);
    
console.log(object);

Note that the file path is resolved with the curent working directory here instead of relative to the js file.

How to import a text file

Maybe in the future there will be assert text. But for now, do the same as JSON without the parsing:

import fsPromises from "node:fs/promises";

const text = await fsPromises.readFile(`./example.txt`, `utf-8`);
    
console.log(text);