Feedsmith

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Parsing Feeds ​

Feedsmith provides powerful parsing capabilities for various feed formats. The library offers both a universal parser that automatically detects feed formats and dedicated parsers for when you know the format in advance.

Universal Feed Parser ​

The simplest way to parse any feed is to use the universal parseFeed function:

typescript
import { parseFeed } from 'feedsmith'

const content = `
  <?xml version="1.0"?>
  <rss version="2.0">
    <channel>
      <title>My Blog</title>
      <description>A blog about web development</description>
      <link>https://example.com</link>
      <item>
        <title>Getting Started with Feedsmith</title>
        <description>Learn how to parse and generate feeds</description>
        <link>https://example.com/posts/feedsmith-intro</link>
        <pubDate>Mon, 15 Jan 2024 12:00:00 GMT</pubDate>
      </item>
    </channel>
  </rss>
`

const result = parseFeed(content)
result.format // rss
result.feed.title // My Blog
result.feed.items?.length // 1
result.feed.items?.[0]?.title // Getting Started with Feedsmith

The universal parser:

  • Automatically detects the feed format using format detection functions
  • Returns an object with format and feed properties
  • Supports RSS, Atom, RDF, and JSON Feed formats
  • Throws DetectError, MalformedError, or ParseError for invalid feeds

IMPORTANT

The universal parser uses detection functions to identify the feed format. While these work well for most feeds, they might not perfectly detect all valid feeds, especially those with non-standard structures. If you know the feed format in advance, using a dedicated parser is more reliable. See more on the feed format detection.

Dedicated Feed Parsers ​

When you know the feed format beforehand, use format-specific parsers for better performance and reliability:

typescript
import {
  parseRssFeed,
  parseAtomFeed,
  parseRdfFeed,
  parseJsonFeed
} from 'feedsmith'

// Parse specific formats
const rssFeed = parseRssFeed(rssContent)
const atomFeed = parseAtomFeed(atomContent)
const rdfFeed = parseRdfFeed(rdfContent)
const jsonFeed = parseJsonFeed(jsonContent)

// Then read the TypeScript suggestions for the specific feed format
rssFeed.title
rssFeed.dc?.creator
rssFeed.dc?.date
rssFeed.sy?.updateBase
rssFeed.items?.[0]?.title

OPML Parser ​

OPML (Outline Processor Markup Language) files, commonly used for feed subscription lists, have their own parser:

typescript
import { parseOpml } from 'feedsmith'

const opml = parseOpml(opmlContent)

// Access OPML structure
opml.head?.title
opml.body?.outlines

Error Handling ​

Parsing functions throw DetectError when the input doesn't match the expected format, MalformedError when the content is malformed, or ParseError when the parsed result is invalid. See Error Handling for details.

Returned Values ​

The parsing functions return JavaScript objects representing the feed in its original structure. See Parsing Examples page for detailed examples of input and output for each feed format.