XML T.R.A.P. - a Typescript RSS/Atom Feed Parser written in Bun

This is a simple RSS/Atom feed parser written in Typescript, using Bun. It can parse feeds and create an AST of the feed in JSON.

Quickstart

npm install xml-trap 

Usage

You can either use the newFeed function to parse a feed, or the createTree function to create an AST of the feed.

Feeds

To parse an RSS Feed, use the newFeed function.

import { newFeed } from "xml-trap";

const feed = await newFeed("https://example.com/feed.xml");
console.log(feed.title) // The title of the feed

The Feed type has a number of fields that can be accessed:

Field	Description
url	The URL of the feed
title	The title of the feed
description	The description of the feed
language	The language of the feed
update	The last build date of the feed (or the updated date)
items	An array of items in the feed
tree	An AST of the feed in JSON
source	A minified copy of the source XML

AST

To create a tree-representation of the feed, use the createTree function.

import { createTree } from "xml-trap";

const tree = createTree("https://example.com/feed.xml");
console.log(tree.root) // The root of the tree

The Tree type has two main fields:

Field	Description
declaration	The XML declaration node
root	The root node of the tree (and all children)

The XMLNode type represents nodes on the tree, with fields:

Field	Description
name	The name of the node eg. div, or the node text
type	The type of the node (eg. Declaration, Opening, Self-closing, etc.)
attributes	An object of attributes on the node
value	The value of the node (eg. the text of a text node)
children	An array of children of the node

This tree is used to construct feeds, and of course can be re-used as you wish for handling other XML documents.

Tests

Both the AST and Feed Parser are well-covered with unit tests, and more end-to-end-ish tests (reading live feeds). To run the tests:

bun test # run the test suite
bun run test/bench.ts # run the benchmarks

Contributing

This project is open to contributions. As you see above, the project is well-covered with tests. If you want to contribute, it would probably be best to either add a URL to the feed tests, or in the case of the AST modules, adding a new XML document and referencing the benchmarks would be a good place to start.

All contributions should have a test, and should pass or improve the existing suite. Don't worry too much about benchmarks, but if you have a contribution that makes the code faster, you're welcome to add a benchmark to show the improvement.

Setup

To get started, follow these steps:

# Clone the repo
gh repo clone knightspore/xml-trap
cd xml-trap 

# Install dependencies
bun install

# Run the example and start exploring
bun run example.ts

# Once you're done, build the project
bun run build
# And submit a PR with your changes

License

This project is licensed under the MIT License. See the LICENSE file for more information.

Shoutouts

• Bun for great JS tooling.
• Tsoding for this video about writing a C compiler in PHP which was my original inspiration to explore parsing.
• Matthew Groff's notes on publishing an NPM package built with Bun.