pimsg 0.1.1

Python library and HTTP server for interacting with macOS Messages via imsg

pimsg

Python library and HTTP server for interacting with macOS iMessage and SMS via imsg.

Overview

pimsg wraps the imsg rpc JSON-RPC 2.0 subprocess interface to provide:

• Python library — typed, Pythonic access to chats, messages, sending, and live watching
• HTTP server — FastAPI-based REST + Server-Sent Events (SSE) API for use by web frontends or other services

imsg must be installed separately on the same macOS machine.

Architecture

pimsg is one layer in a three-tier stack:

[imsg]  ──JSON-RPC 2.0──▶  [pimsg]  ──HTTP/SSE──▶  [web interface]
Swift CLI                   this repo               separate project
macOS only                  Python lib +            Docker container
                            FastAPI server          behind reverse proxy

• imsg — Swift binary, macOS only. Reads ~/Library/Messages/chat.db and sends via AppleScript. Speaks JSON-RPC 2.0 over stdio.
• pimsg — this package. Spawns imsg rpc as a subprocess, wraps it as a Python library and HTTP server. Also runs on the Mac.
• web interface — a separate project (to be created) that consumes the pimsg HTTP API. Can run in Docker on the same Mac or elsewhere on the network.

Connecting Docker to pimsg

The web interface container talks to pimsg on the Mac via host.docker.internal:

Docker container
  └── http://host.docker.internal:8765  →  pimsg (Mac, bound to 0.0.0.0)

For a remote Docker host (different machine), use a Tailscale mesh or SSH tunnel — pimsg itself doesn't need to change. See INSTALL.md for details.

This is local-first software

pimsg only runs on macOS — it cannot be deployed to a cloud server or Linux machine. The Mac running pimsg must have imsg installed, Messages.app signed in, and Full Disk Access granted. The web interface is the only part that's network-portable.

Requirements

• macOS 14+ with Messages.app signed in
• imsg installed (brew install steipete/tap/imsg or built from source)
• Full Disk Access granted to the terminal running pimsg
• Python 3.10+

Install

pip install pimsg

Or from source:

git clone https://github.com/dynacylabs/pimsg.git
cd pimsg
pip install -e ".[dev]"

Library Usage

import pimsg

# List chats
chats = pimsg.list_chats()
for chat in chats:
    print(chat.name, chat.service)

# Get message history for a chat
messages = chat.messages(limit=50)
for message in messages:
    print(message.sender, message.text)

# Send a message
pimsg.send(to="[phone]", text="Hello from Python!")

# Watch for new messages (async generator)
async for message in pimsg.watch(chat_id=1):
    print(message.sender, message.text)

HTTP Server Usage

# Start on default 127.0.0.1:8765
pimsg-server

# Bind to all interfaces (e.g. for Docker — ensure this connection is secured)
pimsg-server --host 0.0.0.0 --port 8765

Endpoints

Method	Path	Description
GET	/chats	List recent chats
GET	/chats/{id}/messages	Message history for a chat
POST	/messages/send	Send a message
GET	/chats/{id}/stream	SSE stream of new messages
GET	/health	Health check

Security

The HTTP server is unauthenticated by default and binds to 127.0.0.1 only. This is intentional — auth is delegated to the user's infrastructure:

• Local Python use: no network involved, no risk.
• Same-Mac Docker: bind to 0.0.0.0, ensure the port is firewalled from external access.
• Remote Docker / web interface: place pimsg behind a reverse proxy or VPN. The web interface project is responsible for end-user authentication.

See INSTALL.md for recommended network setups.

Development

pip install -e ".[dev]"
pytest

See DEVELOPMENT.md for the full development guide.

License

MIT — see LICENSE.