RSS to Bluesky

RSS to Bluesky is a simple, built in a weekend, application that publishes posts from RSS feeds to a Bluesky account with the following features:

Support multiple RSS feed sources

RSS to Bluesky supports multiple RSS feed sources, useful in the following scenarios:

• You want to post from a site that has multiple RSS feeds. This is typically found on news sites that split RSS feeds by topic.
• You run a thematic Bluesky account that wants to post content from multiple sites.

Post with a website card embed using Open Graph data

If available, RSS to Bluesky will use Open Graph data from the RSS feed post URL to create a website card embed including image and description for the Bluesky post. If not available, it will create a simple website card embed.

Removes duplicate RSS feed posts

RSS to Bluesky fingerprints RSS posts and removes any duplicates.

Limit the number of RSS feed posts posted to Bluesky

RSS to Bluesky can optionally limit how many RSS feed posts are processed at a time. This is useful on first run or if the RSS feeds publish too many posts at a time and you don’t want to flood your Bluesky account.

RSS to Bluesky always posts the oldest RSS feed posts first so by using a post limit, you can process a large amount of posts by running RSS to Bluesky with a sensible pause before running again.

Requirements

PHP 8.* with the following modules:

Required:

• SimpleXML - For parsing RSS feeds
• GD - For image manipulation and downsizing
• SQLite3 - For tracking posted items in the database

Optional:

• Memcached - For caching Bluesky authentication credentials to avoid rate limits (see limitations below). Requires a running Memcached server.

Limitations

Rate limits

Every time RSS to Bluesky runs, it uses session tokens to authenticate with Bluesky. These session tokens are obtained via com.atproto.server.createSession which is currently rate limited to 30 requests per 5 minutes and 300 requests per day for each account. If you're running RSS to Bluesky every five minutes, this equates to 288 request a day so should not be an issue but if RSS to Bluesky is run more often, you're likely to exceed rate limits and be unable to post until this rate limit resets.

To get around this limitation, RSS to Bluesky will use local Memcached if available to temporarily store and refresh these tokens so the rate limit is not exceeded. RSS to Bluesky displays messages confirming Memcached is working, if you do not see these messages, be careful with rate limits.

Duplicate posts

To prevent duplicates, RSS to Bluesky fingerprints RSS feed posts and ignores posts with the same fingerprint. This works in most cases but some sites will repost with modified data which defeats duplicate detection. News sites in particular do this during breaking news so there is usually no harm in reposting as information changes.

Configuration

To configure the application, set up a .env file in the same root directory as rss-to-bluesky.php with the following values:

• BLUESKY_HANDLE: The Bluesky account handle you want to post RSS feeds to without the @ mark.
• BLUESKY_APP_PASSWORD: An app password for this Bluesky account. This app password doesn’t need access to direct messages. Don’t be that person who uses the account password instead.
• RSS_FEEDS: A single or comma-separated list of RSS feed URLs you want to post from.

Example .env file for a single RSS feed:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml

Example .env file for multiple RSS feeds:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed1.xml,https://example.com/feed2.xml

RSS to Bluesky also supports the following optional .env values:

• BLUESKY_POST_LANGUAGES: A single or comma-separated list of BCP-47 format post languages. The default post language is 'en'.
• BLUESKY_POST_LIMIT: The maximum amount of RSS feed posts posted to Bluesky at one time. The default post limit is no limit.
• RSS_MAX_AGE: The maximum age in hours in the past an RSS feed post publication date must be below to be posted to Bluesky. The default maximum age is 24 hours.
• BLUESKY_HOST: The Bluesky account hosting provider. Unless you’ve setup your own Bluesky PDS, you don’t need to set this value. The default host is https://bsky.social.
• SHOW_FEED_TITLE: A boolean which when enabled will prepend the feed title with a line break at the top of each Bluesky post. This is useful for thematic accounts that post from multiple sources and want to identify which source each post came from.
• FEED_TITLE_PREFIX: Optional text to prepend before the feed title when SHOW_FEED_TITLE is enabled. Supports escape sequences like \n for line breaks.
• FEED_TITLE_SUFFIX: Optional text to append after the feed title when SHOW_FEED_TITLE is enabled. Supports escape sequences like \n for line breaks.
• DRY_RUN: A boolean which when enabled will do everything except post to Bluesky. Dry run will still authenticate with Bluesky so please keep in mind the limitations above.

Example .env file with Japanese language posts:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
BLUESKY_POST_LANGUAGES=ja

Example .env file with Japanese and English language posts:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
BLUESKY_POST_LANGUAGES=ja,en

Example .env file with a five post limit:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
BLUESKY_POST_LIMIT=5

Example .env file with a maximum RSS feed post age of 2 hours ago:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
RSS_MAX_AGE=2

Example .env file with a custom host:

BLUESKY_HOST=https://bluesky.example.com
BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml

Example .env file with feed title display enabled:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
SHOW_FEED_TITLE=true

Example .env file with feed title prefix and suffix:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
SHOW_FEED_TITLE=true
FEED_TITLE_PREFIX="via "
FEED_TITLE_SUFFIX="\n"

Example .env file with dry run enabled:

BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
DRY_RUN=true

Example .env file with all options:

BLUESKY_HOST=https://bluesky.example.com
BLUESKY_HANDLE=your_bluesky_handle
BLUESKY_APP_PASSWORD=your_bluesky_app_password
RSS_FEEDS=https://example.com/feed.xml
BLUESKY_POST_LANGUAGES=ja
BLUESKY_POST_LIMIT=5
RSS_MAX_AGE=2
SHOW_FEED_TITLE=true
FEED_TITLE_PREFIX="["
FEED_TITLE_SUFFIX="]\n"
DRY_RUN=true

Make sure to keep your .env file secure and do not share it publicly.

Running RSS to Bluesky

To run once in terminal:

php /path/to/rss-to-bluesky.php

To run automatically, use cron:

crontab -e

Then add something like the following to your crontab file and save. This example runs RSS to Bluesky every five minutes, ignoring output:

*/5 * * * * /path/to/php /path/to/rss-to-bluesky.php  > /dev/null 2>&1

Changelog

v1.2.0

• Added FEED_TITLE_PREFIX and FEED_TITLE_SUFFIX options for customizing feed title display
• Feed titles are now displayed in their original case instead of uppercase
• Added support for escape sequences (like \n) in prefix and suffix values

v1.1.0

• Added SHOW_FEED_TITLE option to display feed titles at the top of posts

v1.0.0

• Initial release

Contributing

If you can handle tabs and Allman formatting, fork and drop a pull request.