app_python3s Module

Daniel-Constantin Mierla

Maxim Sobolev

Anthony Alba

Edited by

Daniel-Constantin Mierla

Table of Contents

1. Admin Guide
1. Overview
2. Dependencies
2.1. Kamailio Modules
2.2. External Libraries or Applications
3. Parameters
3.1. load (string)
3.2. script_init (string)
3.3. script_child_init (string)
4. Functions
4.1. app_python3s_exec(method [, param])
5. RPC Commands
5.1. app_python.reload
5.2. app_python.api_list
6. KEMI Usage

List of Examples

1.1. Set load parameter
1.2. Set script_init parameter
1.3. Set script_child_init parameter
1.4. app_python3s_exec usage

Chapter 1. Admin Guide

1. Overview

This module is an alternative 'app_python3' module with static export of 'KSR' object and functions, without instantiating the SIP message object.

This module cannot be loaded together with 'app_python3' as some global symbols conflict.

This module allows executing Python3 scripts from the config file, exporting functions to access the SIP message from Python3.

Note: if symbols exported to KEMI (module or function names) conflict with Python's reserved keywords, use the 'getattr()' function or the '__dict__' attribute for 'KSR' (e.g., 'KSR.__dict__["async"].task_route("myroute")').

2. Dependencies

2.1. Kamailio Modules

The following modules must be loaded before this module:

  • none.

2.2. External Libraries or Applications

The following libraries or applications must be installed before running Kamailio with this module loaded:

  • python3 - Python 3 runtime.

To compile this module the Python 3 development package is needed. Requirements:

  • python3-dev - Python 3 development package.

  • python3-config - (part of python3-dev) tool to output C includes and library paths.

3. Parameters

3.1. load (string)

The path to the file with Python code to be executed from configuration file.

Default value is /usr/local/etc/kamailio/

Example 1.1. Set load parameter

modparam("app_python3s", "load", "/usr/local/etc/kamailio/")

3.2. script_init (string)

The name of the Python function to be executed when the script is loaded or reloaded.

Default value is (not set).

Example 1.2. Set script_init parameter

modparam("app_python3s", "script_init", "ksr_script_init")
def ksr_script_init():"init python script\n")
    return 1

3.3. script_child_init (string)

The name of the Python function to be executed when Kamailio forks child processes at startup and when the script is reloaded.

Default value is (not set).

Example 1.3. Set script_child_init parameter

modparam("app_python3s", "script_child_init", "ksr_script_child_init")
def ksr_script_child_init():"child init python script\n")
    return 1

4. Functions

4.1.  app_python3s_exec(method [, param])

Execute the Python function with the name given by the parameter 'method'. Optionally can be provided a second string with the parameter to be passed to the Python function.

Both parameters can contain pseudo-variables.

Example 1.4. app_python3s_exec usage

app_python3s_exec("my_python_function", "my_params");
app_python3s_exec("my_python_function", "$rU");

5. RPC Commands

5.1.  app_python.reload

IMPORTANT: this is not thread-safe. In your Python script do not use C extensions with threads that call into apy_exec().

Marks the need to reload the Python script. The actual reload is done in each worker when it next invokes a Python method. The module uses a worker process lock to prevent recursive reloads.

This function only reloads (re-executes) the user script and creates a new script object. It does not reinitialize the interpreter (references in the old module remain if not redefined by the new version).

Name: app_python.reload

Parameters: none


kamcmd app_python3s.reload

Note that reload is done for the Python script provided as parameter to this Kamailio module. To reload the Python libraries imported in this script, leverage "script_init" and use something like:

import mod1
import modN
from importlib import reload

def ksr_script_init():
    return kamailio()

Where "modX" are the modules imported at the top.

5.2.  app_python.api_list

List the functions available via Kemi framework.

Name: app_python.api_list

Parameters: none


kamcmd app_python3s.api_list

6. KEMI Usage

The module exports KEMI engine with id "python".


loadmodule ""
cfgengine "python"

For more details about KEMI, see: