Installation

How to install Moler, system requirements, and dependency overview.

Requirements

Python: 3.8, 3.9, 3.10, 3.11, 3.12, 3.13, or 3.14

Operating system: POSIX/Unix (Linux, macOS). Windows is not supported.

Install Moler

Stable release (PyPI)

pip install moler

Use a virtual environment to avoid conflicts with other packages:

python -m venv .venv
source .venv/bin/activate
pip install moler

Verify the installation

Confirm the DeviceFactory and connection factory are importable:

from moler.device import DeviceFactory
from moler.connection_factory import get_connection
print("Moler is ready.")

To check the installed version:

from importlib.metadata import version
print(version("moler"))  # e.g. 4.8.0

Dependencies

Moler installs the following packages automatically:

Package	Description
ptyprocess	Spawns and controls pseudo-terminal (PTY) processes for local terminal connections. Linux/macOS only.
pyyaml >= 5.1	Parses YAML device configuration files passed to load_config().
six	Python 2/3 compatibility utilities used internally.
transitions	Finite state machine library that powers Moler’s device state machines.
apscheduler	Task scheduling used internally for timed events and observers.
psutil	Cross-platform process and system utilities used by local connection handling.
python-dateutil	Extended date/time parsing used in log timestamps and scheduling.
pyserial	Serial port communication support for device connections over RS-232/serial.
cryptography	Cryptographic primitives required by the SSH transport layer.
paramiko	SSH2 protocol implementation for remote device connections.
importlib-metadata	Backport of importlib.metadata for reading installed package metadata on older Pythons.

ptyprocess is only installed on non-Windows platforms. It is required for io_type='terminal' connections. On Windows, this connection type is unavailable.

Installing extras for development

To run the test suite or contribute to Moler, install the development dependencies:

git clone https://github.com/nokia/moler.git
cd moler
pip install -r requirements/base.txt
pip install -r requirements/test.txt  # if present