Wilkins-Software: Http Headers

A set of classes that can be used to programatically generate HTTP headers, with convienient methods of ease of use and readability.

Badges

API Reference

HttpHeaders

HttpHeaders is this Library's main export/tool. It can be instantiated with any standard response header, and can either accept a builder function or a primitive value appropriate to that header.

Builder functions are unique to each particular header, and provide methods to configure that header without having to manually interpolate strings yourself.

For example to generate the following header object...

{
    'Age': '123',
    'Cache-Control': 'max-age=3600, public, immutable',
    'Clear-Site-Data': 'cache',
}

You could use the builders as such:

const headers = new HttpHeaders({
  Age: (builder) => builder.setAge(123),
  "Cache-Control": (builder) =>
    builder
      .setImmutable(true)
      .setIsPublic(true)
      // Note, setMaxAge is passed TimeConverters for your convenience
      .setMaxAge(({ hours }) => hours(1)),
  "Clear-Site-Data": (builder) => builder.setDirective("cache", true),
});

Extending Fetch Headers

The HttpHeaders class extends the built-in fetch Headers class, which means you can pass an instance of HttpHeaders directly to the fetch function as part of the request options.

This allows you to take full advantage of the convenience methods provided by HttpHeaders while still leveraging the compatibility and functionality of the native fetch API.

Here's an example of using HttpHeaders with fetch:

import { HttpHeaders } from "@wilkins-software/http-headers";

const headers = new HttpHeaders({
  "Content-Type": (builder) => builder.setMimeType("application/json"),
  Authorization: (builder) => builder.setBearerToken("your_token_here"),
});

fetch("https://api.example.com/data", {
  method: "GET",
  headers: headers,
})
  .then((response) => response.json())
  .then((data) => console.log(data))
  .catch((error) => console.error("Error:", error));

In this example, we create an instance of HttpHeaders with the desired headers and pass it directly to the fetch function, simplifying the process of setting up headers for your requests.

Currently Supported Headers

Headers	Description
Accept	Media type(s) that is/are acceptable
Accept-CH	Client Hints headers
Accept-CH-Lifetime	Lifetime of Client Hints headers
Accept-Encoding	Acceptable content-codings
Accept-Language	Acceptable languages for response
Accept-Patch	Acceptable patch document formats
Accept-Post	Acceptable media type for POST
Access-Control-*	CORS headers
Age	Age of the response in seconds
Allow	Valid methods for a specific resource
Alt-Svc	Alternate service for a resource
Authorization	Authentication credentials for HTTP auth
Cache-Control	Directives for caching mechanisms
Clear-Site-Data	Clearing browsing data
Content-Type	Media type of the resource
Content-Length	Length of the response body in octets
Content-Language	Natural language of the intended audience
Content-Encoding	Encodings applied to the data
Content-Disposition	How to display the response
Content-Security-Policy	Security policy for the client UI
Cookie	HTTP cookie previously sent by the server
DNT	Do Not Track request
ETag	Entity tag of the associated resource
Expect	Expectations for the server to fulfill
Expires	Date/time after which response is stale
Forwarded	Discloses original information of a client connecting to a web server through an HTTP proxy
From	Email address of the user making the request
Host	Host and port of the resource being requested
If-*	Conditions for HTTP request headers
Keep-Alive	Keep the connection open after the current transaction finishes
Last-Modified	Date and time the resource was last modified
Location	URL of a redirected page
Origin	Initiator of the request
Pragma	Implementation-specific directives
Proxy-*	Request and response behavior of connection via proxy
Range	Request only part of an entity
Referer	Address of the previous web page
Retry-After	If you're rate-limited, when to try again
Server	Details of the software used by the origin server
Set-Cookie	An HTTP cookie
Strict-Transport-Security	HTTP Strict Transport Security
TE	Transfer encodings the user agent is willing to accept
Trailer	Indicate trailer fields in chunked transfer coding
Transfer-Encoding	Form of encoding used to safely transfer the entity to the user
Upgrade	Ask the client to upgrade to another protocol
User-Agent	User agent string of the user agent
Vary	Determine how to match future request headers to decide whether a cached response can be used
Via

Authors

• @mark-wilkins
• @luckyboy125