Signal to Bluesky Bot

A bot that listens for /post commands in a Signal group and automatically posts the message to Bluesky.

Features

• Listens to a specific Signal group for /post commands
• Automatically posts the message content to Bluesky
• Provides feedback in the Signal group about posting status
• Full error handling and logging

Setup

Prerequisites

• Python 3.8+
• uv package manager
• signal-cli installed and configured
• Bluesky account with app password

Installation

1. Install dependencies:

uv sync

2. Create a .env file with your configuration:

BSKY_USER=your-handle.bsky.social
BSKY_PASS=your-app-password
SIGNAL_ACCOUNT=+1234567890
SIGNAL_SOCKET_PATH=/run/user/1000/signal-cli/socket
SIGNAL_GROUP=your-group-id-here

Configuration

Bluesky Setup

1. Go to Bluesky Settings → App Passwords
2. Create a new app password
3. Use your handle (e.g., username.bsky.social) and the app password in the .env file

Signal Setup

1. Install and configure signal-cli
2. Start the signal-cli daemon:

signal-cli -a +1234567890 daemon --socket

3. Get your group ID by monitoring signal-cli output or using the listGroups command

Optional: Redaction

You can configure a list of words to be automatically removed from any text before it is posted to Bluesky (and from the Signal preview description).

• Env var: REDACT_WORDS
• Format: comma-separated values (CSV)
• Matching: case-insensitive, substring removal

Example .env line:

REDACT_WORDS=alice,charlie,projectx

If omitted, no redaction is performed.

Usage

Running with Docker (Recommended)

The easiest way to run the bot is using Docker with the provided justfile commands:

# Build and start the bot
just build
just up

# View logs
just logs

# Stop the bot
just down

# Restart the bot
just restart

The bot will automatically restart unless manually stopped, so you can just set it and forget it.

Available Commands

Use just to see all available commands:

just                 # Show all commands
just build          # Build the Docker image  
just up             # Start the bot (detached)
just down           # Stop the bot
just logs           # View live logs
just status         # Check bot status
just restart        # Restart the bot
just rebuild        # Rebuild and restart
just check-signal   # Verify signal-cli socket
just clean          # Clean up containers

Running Locally (Development)

# Normal mode
uv run python bot.py

# Debug mode (verbose logging)
uv run python bot.py --debug

Using the Bot

In your Signal group, send a message starting with /post followed by the text you want to post to Bluesky:

/post Hello world! This will be posted to Bluesky.

The bot will:

1. Detect the /post command
2. Post the text to Bluesky
3. Reply in Signal with only the Bluesky post URL (and a rich preview)

You can also reply with /post to any message in the group. If your /post message includes a quote (i.e., you replied to a message), the bot will ignore any text typed after /post and will post the quoted message's text instead.

Examples

/post Just deployed a new feature! 🚀

/post Check out this cool project I'm working on:
https://github.com/username/project

/post Multi-line posts work too!
This is the second line.
And this is the third.

# Replying to a message with /post (quote handling)
# The bot will post the quoted message text, ignoring any inline text you add
# Example usage in Signal:
# 1) Reply to a message with just: /post
# 2) Reply to a message with: /post ignore this text
# In both cases, the quoted message content will be posted.

Testing

Run the test suite to verify the bot logic:

uv run python test_bot.py

Logging

The bot provides comprehensive logging:

• Info level: Shows successful operations and status updates
• Debug level: Shows detailed message parsing and API calls
• Error level: Shows failures and exceptions

Security Notes

• Keep your .env file secure and never commit it to version control
• Use Bluesky app passwords instead of your main account password
• The bot only listens to the specific Signal group configured in SIGNAL_GROUP

Troubleshooting

"Could not connect to socket"

• Make sure signal-cli daemon is running
• Check that the socket path in .env matches your system
• Verify the Signal account number is correct

"Failed to authenticate with Bluesky"

• Verify your Bluesky handle and app password are correct
• Check that your Bluesky account is in good standing
• Try creating a new app password

Bot not responding to /post commands

• Check that the message is sent in the correct Signal group
• Verify the group ID in your .env file
• Run with --debug to see detailed message parsing logs