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Roshan Shambharkar
Roshan Shambharkar

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How To Read a local JSON File Using Fetch API

How To Read a local JSON File Using Fetch API

Can I use Fetch on a local JSON file?

  • The standard method that can be used to read

  • JSON files (either locally or uploaded to a server) is the Fetch API.

  • Use the same syntax for both. The only difference is the URL

First Create A .JSON file With name test.json

{
"countries":[
{
   "name": "Indonesia",
   "capital": "Jakarata"
},
{
   "name": "Philippines",
   "capital": "Manila"
  }
 ]
}
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Then create JavaScript file give name fetch.js

fetch("test.json")
.then(response => response.json())
.then(data => showInfo(data));

function showInfo(data) {
console.table(data.countries);
}
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Top comments (7)

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webjose profile image
José Pablo Ramírez Vargas • Edited

Although I admit I didn't ever think this would work, I should ask why is even needed. If you are in a browser, you cannot fetch from the user's file system, and definitely cannot from the server's file system. On the other hand, if you are doing NodeJS, you have the fs module to actually read the file system.

And in both cases, you can statically import JSON.

For the browser (in React, for example):

import myJson from "./myJson.json";
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For NodeJS:

import myJson from "./myJson.json" assert { type: 'json' };
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roshan_100kar profile image
Roshan Shambharkar

agreed

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oztk profile image
Paul Duguet

It's very convenient when you need to mock some external service in a test environment. It means you can read a local file without having to conditionally use require or fs and keep a consistent server application

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thomasheideman profile image
ThomasHeideman

well, actually I needed just this earlier this week, when i was experimenting with some practice project and i noticed i was running out of free api calls, so i created a mock JSON file and fetched that instead 🤷🏻‍♂️

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tobyschonrock profile image
toby-schonrock

Ah thanks this is exactly what I needed.

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saeedjhn profile image
saeedjhn

In node:
err::

TypeError: Failed to parse URL from test.json
[cause]: TypeError [ERR_INVALID_URL]: Invalid URL
input: 'test.json',
code: 'ERR_INVALID_URL'

solution?

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webjose profile image
José Pablo Ramírez Vargas

Read the other comment.