fetch-rails

library0.8.3jsnpmunverified

A lightweight (4kB) wrapper around the GitHub fetch polyfill that automatically includes Rails CSRF tokens in requests. Current version 0.8.3 (last release 2019, low activity). Simplifies JSON, HTML, and text requests for Rails apps by handling CSRF token extraction, parameter encoding, and HTTP status checks. Compared to plain fetch or axios, it provides Rails-specific defaults like JSON headers and credential inclusion.

security

npm install fetch-rails

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · FETCH-RAILS

fetch-rails

securityjavascriptv0.8.3

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default (Fetch)

✓ import Fetch from 'fetch-rails'

✗ const { Fetch } = require('fetch-rails')

ESM default export; CJS require gives the default object, not a named export.

Fetch.json

✓ import Fetch from 'fetch-rails' Fetch.json(url, options)

✗ import { json } from 'fetch-rails'

Methods are on the default export, not separate named exports.

Fetch.postJSON

✓ import Fetch from 'fetch-rails' Fetch.postJSON(url, data)

✗ Fetch.postJSON(url, { body: data })

The method expects data as second argument, not a body option.

Shows basic GET and POST JSON requests including CSRF token handling for Rails backends.

import Fetch from 'fetch-rails'; // GET JSON Fetch.json('https://jsonplaceholder.typicode.com/posts/1') .then(post => console.log(post)) .catch(err => console.error(err)); // POST JSON Fetch.postJSON('https://jsonplaceholder.typicode.com/posts', { title: 'foo', body: 'bar', userId: 1 }).then(post => console.log(post)).catch(err => console.error(err)); // With Rails CSRF auto-inclusion Fetch.json('/api/resource', { search: { q: 'term' } }) .then(data => console.log(data));

Debug

Known issues

deprecatedThe package is no longer actively maintained; last release was in 2019. Consider using modern alternatives or maintain a fork.

fix

Use native fetch with rails-ujs CSRF tokens, or switch to axios with csrf interceptors.

affects: >=0.8.3

gotchaThe package does not include a fetch polyfill; you must provide it separately (e.g., whatwg-fetch) for older browsers like IE 9.

fix

Install whatwg-fetch and import it before fetch-rails in your entry file.

affects: *

gotchaCSRF token extraction relies on a meta tag named 'csrf-token' in the DOM. If the tag is missing or named differently, requests may fail.

fix

Ensure your Rails layout includes <%= csrf_meta_tags %> and that the meta tag name is 'csrf-token'.

affects: *

breakingThe package uses ES modules (import/export) but does not provide a CommonJS build. Direct require() in Node.js will fail.

fix

Use ESM (import) or transpile with Babel/TypeScript.

affects: >=0.8.0

Errors

Common errors & fixes

Uncaught TypeError: Failed to execute 'fetch' on 'Window': Illegal invocation

fetch-rails relies on the global fetch function, which may be overwritten or unavailable in certain environments (e.g., using a polyfill that isn't properly bound).

fix

Ensure a global fetch polyfill (like whatwg-fetch) is loaded and not shadowed by a local variable named fetch.

Uncaught TypeError: Cannot read property 'getAttribute' of null

The meta tag with name 'csrf-token' is not present in the DOM when fetch-rails tries to read the CSRF token.

fix

Insert <%= csrf_meta_tags %> in your Rails layout file (app/views/layouts/application.html.erb).

Uncaught ReferenceError: require is not defined

Using require('fetch-rails') in a browser environment that doesn't support CommonJS modules.

fix

Use ES module import: import Fetch from 'fetch-rails'. If needed, use a bundler like Webpack or Browserify.

Uncaught TypeError: Fetch.json is not a function

Trying to call Fetch.json before the import completes (e.g., due to circular dependencies or incorrect import).

fix

Ensure proper import order; import Fetch from 'fetch-rails' before using Fetch methods.

Upgrade

Version history

0.8.3latest on npm

Audit

Dependencies

whatwg-fetchoptionalpolyfill for fetch API in older browsers (IE 9+) – intended as peer dependency

Agent activity

28 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/MiguelSavignano/fetch-rails ↗

packagefetch-rails ↗

homepagehttps://github.com/MiguelSavignano/fetch-rails#readme ↗