fhempy

fhempy allows the usage of Python 3 (NOT 2!) language to write FHEM modules. Python 3.9 or higher is required, therefore I recommend using bullseye.

This repository includes following working modules:

Installation

Python >=3.8 is required, Python 2 won't work!

Console

Debian 11 (Bullseye)

Copy & paste this command if you are running Debian Bullseye.

sudo apt install python3 python3-pip python3-dev libffi-dev libssl-dev libjpeg-dev zlib1g-dev autoconf build-essential libglib2.0-dev libdbus-1-dev bluez libbluetooth-dev git libprotocol-websocket-perl

Others

Use the following 2 commands if you run Debian 10 (Buster) or older (e.g. stretch, jessie, ...).

sudo apt install python3 python3-pip python3-dev libffi-dev libssl-dev libjpeg-dev zlib1g-dev autoconf build-essential libglib2.0-dev libdbus-1-dev bluez libbluetooth-dev git

sudo cpan Protocol::WebSocket

FHEM

update add https://raw.githubusercontent.com/fhempy/fhempy/master/controls_pythonbinding.txt

update

shutdown restart

define fhempy_local BindingsIo fhempy

Wait a few minutes until fhempy is installed. This might take up to 15 minutes! fhempy_local will show up with a green circle when finished. All further requirements are installed automatically via pip as soon as the specific module is used the first time.

Usage in FHEM (examples)

This are just a few examples for some modules, please see the modules readme linked in the table above for more details

• define castdevice fhempy googlecast "Living Room"
• define eq3bt fhempy eq3bt 00:11:22:33:44:66:77
• define upnp fhempy discover_upnp

fhempy peers (e.g. extend Bluetooth range)

fhempy allows to run modules locally (same device as FHEM runs on) or on remote peers. Those remote peers only make sense if you want to extend the range of bluetooth or want to distribute the load of some modules to other more powerfull devices (e.g. video object detection).

Peer setup (short version)

Only on remote peers, do not run this commands on the FHEM instance. Run this commands with user "pi".

### WARNING: DO THIS COMMAND ONLY ON REMOTE PEER, NOT ON YOUR FHEM INSTANCE ###
pip3 install --upgrade fhempy
# systemd service installation
curl -sL https://raw.githubusercontent.com/fhempy/fhempy/master/install_systemd_fhempy.sh | sudo -E bash -

Peer setup (long version)

Only needed if you didn't run Peer setup (short version). The following steps are only needed if you want to install fhempy on a remote peer, you should not run them on your FHEM installation.

• Install fhempy with user pi: pip3 install --upgrade fhempy
• Make sure your main fhempy instance (within FHEM) is running
• Test fhempy by just running it with user pi, type fhempy and enter. Wait a few seconds until it gets discovered and you see the incoming FHEM connection.
• Systemd configuration for autostart
  • curl -sL https://raw.githubusercontent.com/fhempy/fhempy/master/install_systemd_fhempy.sh | sudo -E bash -
  • fhempy is run with user pi, you can change that in the fhempy.service file in /etc/systemd/system/
• FHEM configuration
  • The remote peer is autodiscovered and will show up in FHEM as device e.g. fhempy_peer_192_168_1_50
  • You can move any device to the remote peer by changing the IODev of the device.
  • If autodiscovery doesn't work (it's based on zeroconf), you can define it with define fhempy_peer_IP BindingsIo IP:15733 fhempy

Log file

journalctl -u fhempy.service -f

Update

Just do set remote_pybinding update and the remote peer will install the new package via pip and restart afterwads.

Functionality

10_BindingsIo

This module is a DevIo device which builds a language neutral communicaton bridge in JSON via websockets.

10_fhempyServer

This module just starts the fhempy server instance

10_fhempy

This module is used as the bridge to BindingsIo. It calls BindingsIo with IOWrite.

fhempy

This is the Python server instance which handles JSON websocket messages from BindingsIo. Based on the message it executes the proper function and replies to BindingsIo via websocket.

Call flow

This example shows how Define function is called from the Python module.

1. define castdevice fhempy googlecast "Living Room"
2. fhempy sends IOWrite to BindingsIo
3. BindingsIo sends a JSON websocket message to fhempy
4. fhempy loads the corresponding module (e.g. googlecast), creates an instance of the object (e.g. googlecast) and calls the Define function on that instance
5. Define function is executed within the Python context, as long as the function is executed, FHEM waits for the answer the same way as it does for Perl modules
6. Python Define returns the result via JSON via websocket to BindingsIo

At any time within the functions FHEM functons like readingsSingleUpdate(...) can be called by using the fhem.py module (fhem.readingsSingleUpdate(...)). There are just a few functions supported at the moment.

Write your own module

Check helloworld example for writing an own module. Be aware that no function which is called from FHEM is allowed to run longer than 1s. In general no blocking code should be used with asyncio. If you want to call blocking code, use utils.run_blocking.