smartfeed/readme.md

# @push.rocks/smartfeed

**The modern TypeScript library for creating and parsing RSS, Atom, and Podcast feeds** 🚀

`@push.rocks/smartfeed` is a powerful, type-safe feed management library that makes creating and parsing RSS 2.0, Atom 1.0, JSON Feed, and Podcast feeds ridiculously easy. Built with TypeScript from the ground up, it offers comprehensive validation, security features, and supports modern podcast standards including iTunes tags and the Podcast namespace.

## Features ✨

- 🎯 **Full TypeScript Support** - Complete type definitions for all feed formats
- 📡 **Multiple Feed Formats** - RSS 2.0, Atom 1.0, JSON Feed 1.0, and Podcast RSS
- 🎙️ **Modern Podcast Support** - iTunes tags, Podcast 2.0 namespace (guid, medium, locked, persons, transcripts, funding)
- 🔒 **Built-in Validation** - Comprehensive validation for URLs, emails, domains, and timestamps
- 🛡️ **Security First** - XSS prevention, content sanitization, and secure defaults
- 📦 **Zero Config** - Works out of the box with sensible defaults
- 🔄 **Feed Parsing** - Parse existing RSS and Atom feeds from strings or URLs
- 🎨 **Flexible API** - Create feeds from scratch or from standardized article arrays

## Installation

```bash
pnpm install @push.rocks/smartfeed
```

## Quick Start

### Creating a Basic Feed

```typescript
import { Smartfeed } from '@push.rocks/smartfeed';

const smartfeed = new Smartfeed();

// Create a feed
const feed = smartfeed.createFeed({
  domain: 'example.com',
  title: 'Tech Insights',
  description: 'Latest insights in technology and innovation',
  category: 'Technology',
  company: 'Example Inc',
  companyEmail: 'hello@example.com',
  companyDomain: 'https://example.com'
});

// Add an item
feed.addItem({
  title: 'TypeScript 5.0 Released',
  timestamp: Date.now(),
  url: 'https://example.com/posts/typescript-5',
  authorName: 'Jane Developer',
  imageUrl: 'https://example.com/images/typescript.jpg',
  content: 'TypeScript 5.0 brings exciting new features...'
});

// Export as RSS, Atom, or JSON
const rss = feed.exportRssFeedString();
const atom = feed.exportAtomFeed();
const json = feed.exportJsonFeed();
```

### Creating a Podcast Feed

```typescript
import { Smartfeed } from '@push.rocks/smartfeed';

const smartfeed = new Smartfeed();

const podcast = smartfeed.createPodcastFeed({
  domain: 'podcast.example.com',
  title: 'The Tech Show',
  description: 'Weekly discussions about technology',
  category: 'Technology',
  company: 'Tech Media Inc',
  companyEmail: 'podcast@example.com',
  companyDomain: 'https://example.com',
  // iTunes tags
  itunesCategory: 'Technology',
  itunesAuthor: 'John Host',
  itunesOwner: {
    name: 'John Host',
    email: 'john@example.com'
  },
  itunesImage: 'https://example.com/artwork.jpg',
  itunesExplicit: false,
  itunesType: 'episodic',
  // Podcast 2.0 tags
  podcastGuid: '92f49cf0-db3e-5c17-8f11-9c5bd9e1f7ec', // Permanent GUID
  podcastMedium: 'podcast', // or 'music', 'video', 'film', 'audiobook', 'newsletter', 'blog'
  podcastLocked: true, // Prevent unauthorized imports
  podcastLockOwner: 'john@example.com'
});

// Add an episode
podcast.addEpisode({
  title: 'Episode 42: The Future of AI',
  authorName: 'John Host',
  imageUrl: 'https://example.com/episode42.jpg',
  timestamp: Date.now(),
  url: 'https://example.com/episodes/42',
  content: 'In this episode, we explore the future of artificial intelligence...',
  audioUrl: 'https://example.com/audio/episode42.mp3',
  audioType: 'audio/mpeg',
  audioLength: 45678900, // bytes
  itunesDuration: 3600, // seconds
  itunesEpisode: 42,
  itunesSeason: 2,
  itunesEpisodeType: 'full',
  itunesExplicit: false,
  // Modern podcast features
  persons: [
    { name: 'John Host', role: 'host' },
    { name: 'Jane Guest', role: 'guest', href: 'https://example.com/jane' }
  ],
  transcripts: [
    { url: 'https://example.com/transcripts/ep42.txt', type: 'text/plain' }
  ],
  funding: [
    { url: 'https://example.com/support', message: 'Support the show!' }
  ]
});

// Export podcast RSS with iTunes and Podcast namespace
const podcastRss = podcast.exportPodcastRss();
```

### Parsing Existing Feeds

```typescript
import { Smartfeed } from '@push.rocks/smartfeed';

const smartfeed = new Smartfeed();

// Parse from URL
const feed = await smartfeed.parseFeedFromUrl('https://example.com/feed.xml');
console.log(feed.title);
console.log(feed.items.map(item => item.title));

// Parse from string
const xmlString = '<rss>...</rss>';
const parsedFeed = await smartfeed.parseFeedFromString(xmlString);
```

### Creating Feeds from Article Arrays

```typescript
import { Smartfeed } from '@push.rocks/smartfeed';
import type { IArticle } from '@tsclass/tsclass';

const smartfeed = new Smartfeed();

const articles: IArticle[] = [
  // Your article objects conforming to @tsclass/tsclass IArticle interface
];

const feedOptions = {
  domain: 'blog.example.com',
  title: 'My Blog',
  description: 'Thoughts on code and design',
  category: 'Programming',
  company: 'Example Inc',
  companyEmail: 'blog@example.com',
  companyDomain: 'https://example.com'
};

// Creates an Atom feed from articles
const atomFeed = await smartfeed.createFeedFromArticleArray(feedOptions, articles);
```

## API Reference

### Smartfeed Class

The main class for creating and parsing feeds.

#### `createFeed(options: IFeedOptions): Feed`

Creates a standard feed (RSS/Atom/JSON).

**Options:**
- `domain` (string) - Feed domain (e.g., 'example.com')
- `title` (string) - Feed title
- `description` (string) - Feed description
- `category` (string) - Feed category
- `company` (string) - Company/organization name
- `companyEmail` (string) - Contact email
- `companyDomain` (string) - Company website URL (absolute)

#### `createPodcastFeed(options: IPodcastFeedOptions): PodcastFeed`

Creates a podcast feed with iTunes and Podcast namespace support.

**iTunes Options:**
- `itunesCategory` (string) - iTunes category
- `itunesSubcategory` (string, optional) - iTunes subcategory
- `itunesAuthor` (string) - Podcast author
- `itunesOwner` (object) - Owner info with `name` and `email`
- `itunesImage` (string) - Artwork URL (1400x1400 to 3000x3000, JPG/PNG)
- `itunesExplicit` (boolean) - Explicit content flag
- `itunesType` ('episodic' | 'serial', optional) - Podcast type
- `itunesSummary` (string, optional) - Detailed summary
- `copyright` (string, optional) - Custom copyright
- `language` (string, optional) - Language code (default: 'en')

**Podcast 2.0 Options:**
- `podcastGuid` (string) - **Required.** Globally unique identifier (GUID) for the podcast
- `podcastMedium` ('podcast' | 'music' | 'video' | 'film' | 'audiobook' | 'newsletter' | 'blog', optional) - Content medium type
- `podcastLocked` (boolean, optional) - Prevents unauthorized podcast imports (e.g., to other platforms)
- `podcastLockOwner` (string, optional) - Email of who can unlock (required if `podcastLocked` is true)

#### `parseFeedFromUrl(url: string): Promise<ParsedFeed>`

Parses an RSS or Atom feed from a URL.

#### `parseFeedFromString(xmlString: string): Promise<ParsedFeed>`

Parses an RSS or Atom feed from an XML string.

#### `createFeedFromArticleArray(options: IFeedOptions, articles: IArticle[]): Promise<string>`

Creates an Atom feed from an array of `@tsclass/tsclass` article objects.

### Feed Class

Represents a feed that can be exported in multiple formats.

#### `addItem(item: IFeedItem): void`

Adds an item to the feed.

**Item Properties:**
- `title` (string) - Item title
- `timestamp` (number) - Unix timestamp in milliseconds
- `url` (string) - Absolute URL to the item
- `authorName` (string) - Author name
- `imageUrl` (string) - Absolute URL to featured image
- `content` (string) - Item content/description
- `id` (string, optional) - Unique identifier (uses URL if not provided)

#### `exportRssFeedString(): string`

Exports the feed as RSS 2.0 XML.

#### `exportAtomFeed(): string`

Exports the feed as Atom 1.0 XML.

#### `exportJsonFeed(): string`

Exports the feed as JSON Feed 1.0.

### PodcastFeed Class

Extends `Feed` with podcast-specific functionality.

#### `addEpisode(episode: IPodcastItem): void`

Adds a podcast episode to the feed.

**Episode Properties (in addition to IFeedItem):**
- `audioUrl` (string) - Absolute URL to audio file
- `audioType` (string) - MIME type (e.g., 'audio/mpeg')
- `audioLength` (number) - File size in bytes
- `itunesDuration` (number) - Duration in seconds
- `itunesEpisode` (number, optional) - Episode number
- `itunesSeason` (number, optional) - Season number
- `itunesEpisodeType` ('full' | 'trailer' | 'bonus', optional)
- `itunesExplicit` (boolean, optional) - Explicit content flag
- `itunesSubtitle` (string, optional) - Short description
- `itunesSummary` (string, optional) - Detailed summary
- `persons` (array, optional) - People involved (hosts, guests)
- `chapters` (array, optional) - Chapter markers
- `transcripts` (array, optional) - Transcript links
- `funding` (array, optional) - Donation/support links

#### `exportPodcastRss(): string`

Exports the podcast feed as RSS 2.0 with iTunes and Podcast namespace extensions.

## Validation & Security

`@push.rocks/smartfeed` includes comprehensive validation to ensure feed integrity and security:

- **URL Validation** - All URLs must be absolute and use http/https protocols
- **Email Validation** - Email addresses are validated against RFC standards
- **Domain Validation** - Proper domain format checking
- **Timestamp Validation** - Ensures timestamps are valid and reasonable
- **Content Sanitization** - Prevents XSS attacks through proper XML escaping
- **Duplicate Detection** - Prevents duplicate item IDs in feeds
- **Required Field Checking** - Validates all required fields are present

## Best Practices

### Feed Item IDs

Feed item IDs should be permanent and never change once published. This allows feed readers to properly track which items have been read:

```typescript
feed.addItem({
  id: 'post-2024-01-15-typescript-tips', // Permanent ID
  title: 'TypeScript Tips',
  url: 'https://example.com/posts/typescript-tips',
  // ... other fields
});
```

If you don't provide an `id`, the `url` will be used. Make sure URLs don't change for published items.

### HTTPS URLs

Always use HTTPS URLs for security and privacy. The library will warn you if HTTP URLs are used:

```typescript
// ✅ Good
imageUrl: 'https://example.com/image.jpg'

// ⚠️ Will trigger a warning
imageUrl: 'http://example.com/image.jpg'
```

### Podcast Artwork

For podcast feeds, artwork should be:
- Square (1:1 aspect ratio)
- Between 1400x1400 and 3000x3000 pixels
- JPG or PNG format
- Maximum 512 KB file size (Apple Podcasts requirement)

### Podcast 2.0 Compatibility

The library fully supports the [Podcast 2.0 namespace](https://github.com/Podcastindex-org/podcast-namespace), making your feeds compatible with modern podcast platforms like:

- **Podcast Index** - The open podcast directory
- **Castopod** - Open-source podcast hosting platform
- **Podverse** - Open-source podcast app
- And other Podcast 2.0-compliant apps

**Key Podcast 2.0 Features:**
- `podcast:guid` - Permanent unique identifier for your podcast
- `podcast:medium` - Declare if your feed is a podcast, music, video, etc.
- `podcast:locked` - Protect your podcast from unauthorized imports
- `podcast:person` - List hosts, co-hosts, and guests with rich metadata
- `podcast:transcript` - Link to transcript files in various formats
- `podcast:funding` - Add donation/support links for your listeners

These features are included in the RSS export when you use `exportPodcastRss()`.

## TypeScript Support

Full TypeScript definitions are included. Import types as needed:

```typescript
import type {
  IFeedOptions,
  IFeedItem,
  IPodcastFeedOptions,
  IPodcastItem,
  IPodcastOwner,
  IPodcastPerson,
  IPodcastChapter,
  IPodcastTranscript,
  IPodcastFunding
} from '@push.rocks/smartfeed';
```

## Why @push.rocks/smartfeed?

- **Type-Safe** - Catch errors at compile time, not runtime
- **Modern Standards** - Full support for latest podcast specifications
- **Secure by Default** - Built-in validation and sanitization
- **Developer Friendly** - Intuitive API with great error messages
- **Well Tested** - Comprehensive test suite ensuring reliability
- **Actively Maintained** - Regular updates and improvements

## License and Legal Information

This repository contains open-source code that is licensed under the MIT License. A copy of the MIT License can be found in the [license](license) file within this repository.

**Please note:** The MIT License does not grant permission to use the trade names, trademarks, service marks, or product names of the project, except as required for reasonable and customary use in describing the origin of the work and reproducing the content of the NOTICE file.

### Trademarks

This project is owned and maintained by Task Venture Capital GmbH. The names and logos associated with Task Venture Capital GmbH and any related products or services are trademarks of Task Venture Capital GmbH and are not included within the scope of the MIT license granted herein. Use of these trademarks must comply with Task Venture Capital GmbH's Trademark Guidelines, and any usage must be approved in writing by Task Venture Capital GmbH.

### Company Information

Task Venture Capital GmbH
Registered at District court Bremen HRB 35230 HB, Germany

For any legal inquiries or if you require further information, please contact us via email at hello@task.vc.

By using this repository, you acknowledge that you have read this section, agree to comply with its terms, and understand that the licensing of the code does not imply endorsement by Task Venture Capital GmbH of any derivative works.