Radiation Monitor Python Script Documentation

API

DBus Quick Reference

Service Bus: SessionBus()

Service Name: iac.nagios.radmonitors

Service Path: /IAC/Nagios/RadMonitors

Exposed Methods

get_active_channels()
get_active_monitors()
get_active_monitor_count()
get_radiation_levels()
add_send_client(string)
reload_configuration()

DBus Interaction

Before you can interact with the Radiation Monitor's DBus service, you will need to load some prerequisite Python libraries:

import dbus

This is the minimum to connect to DBus. If you wish to do more than connect as a client, you will need to load the following libraries:

import dbus.service, gobject
from dbus import glib

It is also recommend that you initialize threading now if you are planning on performing threaded tasks:

gobject.threads_init()
glib.init_threads()

Connecting to the Radiation Monitor DBus service

To interact with the Radiation Monitor DBus service in Python, you will first need to connect to the DBus Session bus:

dbus_bus = dbus.SessionBus()

Once you have successfully connected to the session bus, you will then want to get the DBus service object for the Radiation Monitor. This is done via the get_object bus method:

dbus_object = dbus_bus.get_object(service_name, service_path)

For our Radiation Monitor interface, the proper invocation is as follows:

dbus_object = dbus_bus.get_object("iac.nagios.radmonitors", "/IAC/Nagios/RadMonitors")

After this is done, you may choose to call the Radiation Monitor's DBus methods either through the service object itself, or you may create references to specific methods for use:

dbus_method_ref = dbus_object.get_dbus_method(method, service_name)

Example:

>>> remote_method = remote_object.get_dbus_method('get_active_monitor_count', 'iac.nagios.radmonitors')
>>> remote_method()
dbus.Int32(7)

Introspection Schema

The Radiation Monitor DBus service returns the following schema upon being called with its inherited Introspect() method:

<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<node name="/IAC/Nagios/RadMonitors">
  <interface name="iac.nagios.radmonitors">
    <method name="reload_configuration">
    </method>
    <method name="get_active_monitors">
    </method>
    <method name="get_active_monitor_count">
    </method>
    <method name="add_send_client">
      <arg direction="in"  type="v" name="new_client" />
    </method>
    <method name="get_radiation_levels">
    </method>
    <method name="get_active_channels">
    </method>
  </interface>
  <interface name="org.freedesktop.DBus.Introspectable">
    <method name="Introspect">
      <arg direction="out" type="s" />
    </method>
  </interface>
</node>

Methods

get_active_channels

This exposed DBus method will return a dbus.Array value representing the active channels the script sees. It is invoked in the following manner:

dbus_object.get_active_channels()

Example output:

>>> remote_object.get_active_channels()
dbus.Array([dbus.Int32(1), dbus.Int32(2), dbus.Int32(3), dbus.Int32(4), dbus.Int32(5), dbus.Int32(6), dbus.Int32(7)], signature=dbus.Signature('i'))

get_active_monitors

This exposed DBus method will return a dbus.Array value representing the IP address of all radiation monitors the script sees. It is invoked in the following manner:

dbus_object.get_active_monitors()

Example output:

>>> remote_object.get_active_monitors()
dbus.Array([dbus.String(u'192.168.40.155'), dbus.String(u'192.168.40.154'), dbus.String(u'192.168.40.121'), dbus.String(u'192.168.40.172'),
dbus.String(u'192.168.40.137'), dbus.String(u'192.168.40.159'), dbus.String(u'192.168.40.120')], signature=dbus.Signature('s'))

get_active_monitor_count

This exposed DBus method will return a dbus.Int32 value representing the total number of active monitors the script sees. It is invoked in the following manner:

dbus_object.get_active_monitor_count()

Example output:

>>> remote_object.get_active_monitor_count()
dbus.Int32(7)

get_radiation_levels

This exposed DBus method will return a dbus.Array value representing the current radiation level of all monitors the script sees. It is invoked in the following manner:

dbus_object.get_radiation_levels()

Example output:

>>> remote_object.get_radiation_levels()
dbus.Array([dbus.String(u'0.0'), dbus.String(u'0.0'), dbus.String(u'0.0'), dbus.String(u'0.0'), dbus.String(u'0.1'), dbus.String(u'0.1'),
dbus.String(u'0.1')], signature=dbus.Signature('s'))

add_send_client

This exposed DBus method will add a new send target client to a running instance of the script, allowing for on-the-fly addition of targets without restarting. It is invoked in the following manner:

dbus_object.add_send_client(string)

Where string is a string containing the IP address and destination port number of the send target, formatted as "ip:port". The function returns a dbus.Boolean value; True if the add is successful, False if not.

Example output:

>>> remote_object.add_send_client("134.50.87.179:55555")
dbus.Boolean(True)

reload_configuration

This exposed DBus method will cause a running instance of the script to reload its configuration file, as if having been sent signal SIGHUP. It is invoked in the following manner:

dbus_object.reload_configuration()

Then function always returns dbus.Boolean True at this time.

Example output:

>>> remote_object.reload_configuration()
dbus.Boolean(True)