PY-SIL Development Environment

This section outlines instructions for a minimal installation.

External Packages Needed by PY-SIL

There are several components needed in the YumaPro PY-SIL software development environment:

Python with pip

  • Python, with a minimum version of 3.8.10, is needed for the PY-SIL environment.

  • pip, the package installer for Python, is included by default with Python installations.

  • Detailed instructions for installing Python can be found in the Python documentation.

Python libraries

The following external python libraries are needed by PY-SIL:

  • wheel

  • pyang

The following shared libraries needed for PY-SIL to operate:

  • libyumapro_ncx.so.

  • libyumapro_agt.so.

  • libyumapro_ycontrol.so.

  • libcurl.so

  • libssl.so

Building the Server to Support PY-SIL Libraries

To enable PY-SIL support on the server, it should be built with the WITH_PY_SIL option.

WITH_PY_SIL=1: build the netconfd-pro server with PY-SIL library support.

If provided, the PY-SIL Python libraries will be installed within the virtual environment. Otherwise, it will be installed globally.

See Creating and Using a Python Virtual Environment if you want install PY-SIL into virtual environment.

Example build command.

mydir> make DEBUG=1 DEBUG2=1 USE_WERROR=1 EVERYTHING=1 WITH_PY_SIL=1
Installed Programs:

  • /usr/bin/py-sil-app.py

Installed pyang plugin:

  • py-sil-gen.py

Installed Python Libraries:

  • pysilcommonlibrary

  • pycontrollibrary

  • pyncxlibrary

  • pysillibrary

  • This feature is not enabled with the EVERYTHING make flag.

Using PY-SIL Libraries with Netconfd-pro

Static Configuration

At startup, py-sil-app.py will retrieve the server configuration and attempt to load the PY-SIL libraries specified by the --module or --bundle parameters to the server.

Dynamic Configuration

Libraries for a single module are loaded at run-time into the server with the <load> operation and removed with the <unload> operation.

PY-SIL Code Generation with 'py-sil-gen.py' Plugin

The 'py-sil-gen.py' plugin for pyang can be used to generate PY-SIL code stub files for a single or multiple YANG modules.

Refer to PY-SIL Code Generation for more details

Creating and Using a Python Virtual Environment

This is an optional step.

Creating a virtual environment in Python is a straightforward process. Here's a step-by-step example using the venv module, which is included in Python 3 and higher:

  1. Navigate to Your Project Directory: Open a terminal or command prompt and navigate to the directory where you want to create the virtual environment.

  2. Create the Virtual Environment: Run the following command to create a virtual environment named myenv:

    python3 -m venv myenv

    If you're using Windows and your default Python interpreter is Python 3, you might use python instead of python3.

  3. Activate the Virtual Environment:

    • On macOS and Linux:

      source myenv/bin/activate

    After activation, you'll see (myenv) in your command prompt, indicating that the virtual environment is active.

  4. Install Packages: Once the virtual environment is activated, you can build server. All PY-SIL packages will be installed locally within the virtual environment.

  5. Deactivate the Virtual Environment: To deactivate the virtual environment and return to your global Python environment, simply run:

    deactivate

That's it! You've created a virtual environment, installed packages, and activated and deactivated it as needed. This approach helps isolate dependencies for different projects.