fetchUtils

FetchUtils is a utility module that adds the following features to the Javascript Fetch API:

• Request timeouts, which the Fetch API currently lacks
• Helper methods for requesting and parsing a JSON- or HTML-encoded response data from an endpoint

Demo

You can view a demo of fetchUtils here.

Install

As of version 3.0.0, fetchUtils is on NPM and can be installed with

npm install @degjs/fetch-utils

Usage

FetchUtils is a singleton, so it does not need to be instantiated.

import fetchUtils from "@degjs/fetch-utils";

/* Success handler */
function onSuccess(data) {
    console.log("SUCCESS: " + data);
}

/* Error handler */
function onError(error) {
    console.log("ERROR: " + error);
}

/* Perform a GET request with a 30-second timeout and expect a JSON-encoded response */
let fetchParams = {
	method: 'GET'
};

let options = {
	timeout: 30000
};

fetchUtils.getJSON('/endpoint-url', fetchParams, options)
    .then(onSuccess)
    .catch(onError);

Methods

.getHTML(url [, fetchParams [, options]])

Returns: Promise
Perform a request to an endpoint that returns HTML-encoded data. Sets the Accept option on request header to text/html.

.getJSON(url [, fetchParams [, options]])

Returns: Promise
Perform a request to an endpoint that returns JSON-encoded data. Sets the Accept option on request header to application/json.

.fetch(url [, fetchParams [, options]])

Returns: Promise
Perform a request to an endpoint that returns the full, unparsed endpoint response.

The parameters for the .getHTML(), .getJSON() and .fetch() methods are outlined below:

url

Type: String
The URL of the endpoint. This parameter is required.

fetchParams

Type: Object
Request options that are passed through to the fetch() method. These options correspond to those defined in the Fetch API. This parameter is optional.

options

Type: Object
Additional options that fall outside of the Fetch API. This parameter is optional.

options.timeout

Type: Number
The number of milliseconds that the request should wait before timing out. The default timeout value is 10,000 millseconds (10 seconds).

.setCallback(functionName)

Define a callback function that will be executed on fetch success. This is not recommended in most scenarios (use .then() and .catch() from the returned promise instead), but may be useful in specific situations.

.setOptions(options)

Override default plugin options, such as timeout and cachebusting. Must be called before any of the fetch methods above are called.

Browser Support

FetchUtils depends on the following browser APIs:

• Fetch
• Promise
• Object.assign

To support legacy browsers, you'll need to include polyfills for the above APIs.