Reddit RSS API

A Deno-powered HTTP service that turns Reddit subreddit RSS feeds into structured JSON, complete with filtering, sorting, merging, and random selection utilities.

Resources

• GitHub Repository
• Live API
• GitHub Issues

Table of Contents

• Features
• API Overview
• Path Parameters
• Query Parameters
• Usage Examples
• Response Shape
• Error Handling
• Development
  • Quick Start
  • Helpful Tasks
  • Architecture
  • Testing

Features

• Merge multiple subreddits by delegating individual RSS requests and consolidating the payload for richer result sets.
• Filter feed items to media-rich posts (images or videos) or fetch a random post from any combination of subreddits.
• Sort posts by publish date (asc, desc) or shuffle them (mixed).
• Limit response size with count while retaining the original itemsLength for reference.
• Rewrite all Reddit links to old.reddit.com on demand for legacy views.
• CORS-friendly JSON responses served by [Deno.serve](https://deno.land/api?s=Deno.serve) with a zero-dependency runtime.

API Overview

• Base URL: https://reddit-rss-api.deno.dev
• Root (GET /): renders the Markdown README as HTML for quick documentation access.
• Feed (GET /r/{subreddits}): fetches RSS-derived JSON for one or more subreddits.

Path Parameters

• subreddits – one or more subreddit names separated by + (URL-encoded space). Example: deno+typescript.

Query Parameters

• option (string)

  • Values: random
  • Default: null
  • Description: Returns a single random item from the processed feed.

• sort (string)

  • Values: asc, desc, mixed
  • Default: asc
  • Description: Orders items by publish date or shuffles them (mixed). Applied before count.

• filter (string)

  • Values: image, video, image+video
  • Default: null
  • Description: Keeps only media-rich posts. Combine options with + (decoded as space).

• merge (boolean)

  • Values: true, false
  • Default: false
  • Description: When true, the API fetches each subreddit individually and merges the results.

• count (number)

  • Values: >= 1
  • Default: null
  • Description: Truncates the response to the first n items after all other operations.

• old_reddit (boolean)

  • Values: true, false
  • Default: false
  • Description: Rewrites feed and item links to use old.reddit.com.

Combine parameters to compose custom feeds. Validation errors produce informative 400 Bad Request messages. When option=random is used, the response is a single ExtractedItem object instead of the full feed payload.

Usage Examples

Fetch the Latest Posts from a Single Subreddit

curl "https://reddit-rss-api.deno.dev/r/deno"

Merge Two Subreddits and Return Only Image Posts

curl "https://reddit-rss-api.deno.dev/r/deno+typescript?merge=true&filter=image"

Get a Random Video Post with Old Reddit Links

curl "https://reddit-rss-api.deno.dev/r/memes+videos?filter=video&option=random&old_reddit=true"

Limit the Response to Five Items, Sorted Descending

curl "https://reddit-rss-api.deno.dev/r/pics?sort=desc&count=5"

Response Shape

type ResponseData = {
 title: string;
 lastBuildDate: Date;
 link: string;
 feedUrl: string;
 itemsLength?: number;
 items: ExtractedItem[];
};

type ExtractedItem = {
 title: string;
 link: string;
 author: string;
 isoDate: Date;
 feedURL: string;
 id: string;
 message?: string;
 links?: string[];
 images?: string[];
 videos?: string[];
};

Sample response (GET /r/deno?count=2):

{
 "title": "posts from r/deno",
 "lastBuildDate": "2024-04-09T12:34:56.000Z",
 "link": "https://www.reddit.com/r/deno/",
 "feedUrl": "https://www.reddit.com/r/deno/.rss",
 "itemsLength": 2,
 "items": [
  {
   "title": "Deno 1.41 release highlights",
   "link": "https://www.reddit.com/r/deno/comments/abc123/...",
   "author": "user123",
   "isoDate": "2024-04-09T09:12:34.000Z",
   "feedURL": "https://www.reddit.com/r/deno/.rss",
   "id": "t3_abc123",
   "links": ["https://example.com/blog-post"],
   "images": ["https://i.redd.it/xyz.png"]
  },
  {
   "title": "Working with kv storage",
   "link": "https://www.reddit.com/r/deno/comments/def456/...",
   "author": "user456",
   "isoDate": "2024-04-08T16:20:10.000Z",
   "feedURL": "https://www.reddit.com/r/deno/.rss",
   "id": "t3_def456"
  }
 ]
}

Error Handling

• 400 Bad Request for invalid paths, malformed query parameters, or RSS parsing failures.
• 405 Method Not Allowed for non-GET requests.
• Error bodies include the message where available to simplify debugging.

Development

To contribute to the project, follow these steps:

1. Fork the repository.
2. Create a new branch for your feature or bug fix.
3. Make your changes and ensure all tests pass.
4. Submit a pull request describing your changes.

Quick Start

1. Install Deno (v1.41 or newer recommended).

2. Clone the repository and switch into the project directory.

3. Run the server:

   deno run start

   The service listens on http://localhost:8000 by default.

Helpful Tasks

• deno run start – run the API once with full permissions.
• deno run dev – watch mode for local development.
• deno run test – execute the unit test suite under src/tests/.
• deno run fmt – format codebase.

Architecture

• index.ts – HTTP entry point. Routes requests, serves the README as HTML, and wires query processing.
• src/utils/fetch.ts – Fetches and parses RSS feeds with rss-parser, normalizes links, and extracts items.
• src/utils/handlers.ts – Orchestrates query parameter handling (merge, sort, filter, random, count, old Reddit toggles).
• src/utils/utils.ts – Shared helpers (CORS responses, merged feed builder, numeric validation).
• src/utils/extracters.ts – Parses HTML content, surfaces media URLs, and rewrites Reddit domains when requested.
• src/utils/html.ts – Renders the README through deno_dom for the root HTML response.
• src/tests/tests.ts – Unit tests verifying feed parsing, query validation, and Reddit URL construction.

Testing

Run the full suite with:

deno run test

Tests rely on live Reddit RSS endpoints; ensure you have network access when executing them.