RSS Render Backend

This is a backend service built with Deno for fetching, parsing, and serving RSS feeds. It also includes a "read later" functionality.

Features

• RSS Feed Fetching and Parsing: Fetches RSS feeds from provided URLs, parses them, and returns structured data.
• Caching: Implements a caching mechanism to reduce redundant fetching and improve response times.
• "Read Later" Functionality: Allows users to save articles for later reading.
• CORS Support: Enables Cross-Origin Resource Sharing for wider accessibility.

Technologies Used

• Deno: A modern runtime for JavaScript and TypeScript.
• Deno Standard Modules: For HTTP server, path manipulation, and file system operations.
• deno-rss: A Deno module for parsing RSS feeds.
• case: A Deno module for converting strings to different cases (e.g., title case, upper case).

Setup

Prerequisites

• Deno installed on your system.

Installation

1. Clone the repository:

   git clone <repository-url>
   cd rss-render
   cd backend

2. Set up environment variables:

   • DENO_KV_URL: URL for Deno KV database. You can use a local or remote KV store.

   You can set these in your .env file or directly in your shell.

Running the Service

deno run --allow-net --allow-read --allow-env --allow-write --allow-run server.ts

Alternatively, if you are using a Deno configuration file (e.g., deno.json or deno.jsonc):

deno run --config deno.json server.ts

The server will start on port 17385 by default, or the port specified in the PORT environment variable.

API Endpoints

GET /api/feeds or POST /api/feeds

• Fetches and parses RSS feeds.

• Method: GET or POST

• Query Parameters (GET):

  • u: Comma-separated list of RSS feed URLs (URL-encoded).
  • l: Limit the number of items returned per feed (optional, default: 12).
  • x: Hash for KV storage (optional).
  • v: Version of the hash (optional).

• Request Body (POST):

  {
    "keys": [
      {"url": "rss_feed_url_1"},
      {"url": "rss_feed_url_2", "content": "rss_feed_content"}
    ],
    "batch": [
      {"url": "rss_feed_url_1"},
      {"url": "rss_feed_url_2", "content": "rss_feed_content"}
    ],
    "update": true
  }

• Response:

  {
    "feeds": [
      {
        "title": "FEED_TITLE > Feed Title",
        "link": "feed_website_url",
        "rss_url": "rss_feed_url",
        "image": "feed_image_url",
        "order": 0,
        "items": [
          {
            "link": "article_url",
            "title": "Article Title",
            "author": "Author Name",
            "description": "Article Description",
            "published": 1678886400000,
            "updated": 1678886400000,
            "images": ["image_url_1", "image_url_2"],
            "categories": ["Category 1", "Category 2"]
          }
        ]
      }
    ],
    "hash": "unique_hash"
  }

GET /api/readlater

• Retrieves saved "read later" items.
• Method: GET
• Query Parameters:
  • x: Hash to identify the user or context (optional, default: 'default').
• Response:

  [
    {
      "link": "article_url",
      "title": "Article Title",
      "description": "Article Description",
      "image_thumb": "thumbnail_url",
      "addedAt": "timestamp",
      "updatedAt": "timestamp"
    }
  ]

POST /api/readlater

• Adds or updates a "read later" item.
• Method: POST
• Request Body:

  {
    "x": "user_hash",
    "item": {
      "link": "article_url",
      "title": "Article Title",
      "description": "Article Description",
      "image_thumb": "thumbnail_url"
    }
  }

• Response:

  {
    "success": true,
    "items": [
      {
        "link": "article_url",
        "title": "Article Title",
        "description": "Article Description",
        "image_thumb": "thumbnail_url",
        "addedAt": "timestamp",
        "updatedAt": "timestamp"
      }
    ],
    "data": {
      "x": "user_hash",
      "item": {
        "link": "article_url",
        "title": "Article Title",
        "description": "Article Description",
        "image_thumb": "thumbnail_url"
      }
    }
  }

DELETE /api/readlater

• Deletes a "read later" item.
• Method: DELETE
• Request Body:

  {
    "x": "user_hash",
    "link": "article_url"
  }

• Response:

  {
    "success": true,
    "items": [
      {
        "link": "article_url",
        "title": "Article Title",
        "description": "Article Description",
        "image_thumb": "thumbnail_url",
        "addedAt": "timestamp",
        "updatedAt": "timestamp"
      }
    ]
  }

GET /html

• Fetches the HTML content of a given URL.
• Method: GET
• Query Parameters:
  • u: URL to fetch (URL-encoded).
• Response:
  • Returns the HTML content of the URL.

Caching Strategy

The service uses a combination of in-memory caching and Deno KV for storing fetched RSS feeds and HTML content.

• In-Memory Cache: Utilizes a Map to store frequently accessed data, with a TTL (time-to-live) of 7 days.
• Deno KV: Used for persistent storage of "read later" items and potentially for longer-term caching of RSS feed data.

Environment Variables

• DENO_KV_URL: The URL for the Deno KV database. If not provided, Deno KV will default to a local database.
• PORT: The port on which the server will listen (default: 17385).

Notes

• The service attempts to extract relevant information from RSS feeds, including images, descriptions, and categories.
• Error handling is implemented to gracefully handle issues such as failed feed fetching or parsing errors.
• The handleRequest function serves as the main request handler, routing requests to the appropriate API endpoints or serving static files from the frontend directory.

Contributing

Feel free to contribute to this project by submitting issues or pull requests.

License

MIT

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"In the Information Age, ignorance is a choice.", "It's not the news, it's how you get the news.", "We just decided to try to do it better." — Will McAvoy, The Newsroom by Aaron Sorkin