channels

This project contains command-line and DBus frontends to Semplice's libchannels.

Design

To avoid duplicating efforts, both the command-line frontend and the DBus service use the same underlying code.

This means that behaviour is modified at runtime (well, everything in Python is at runtime...) and thus it might be a bit difficult to follow what happens.

A core part is the @channels.actions.action decorator. This, based on the handler type set at runtime, properly set-ups the actions. Actions that should be shown only on the cli handler (dbus_visible=False) will be replaced by NoneType objects on DBus. The same happens on actions that should be shown only on DBus (command=None).

Usage

Command-line

The command syntax is channels [action] [action_arguments]

For example, to list every available channel:

g7@meddle:~/semplice/channels/channels$ channels list
jessie
sample
semplice-current (enabled)
semplice-devel
semplice-jessie
sid (enabled)
g7@meddle:~/semplice/channels/channels$ 

...and to query the status of one specific channel:

g7@meddle:~/semplice/channels/channels$ channels get-enabled semplice-current
True
g7@meddle:~/semplice/channels/channels$ channels get-enabled semplice-jessie
False
g7@meddle:~/semplice/channels/channels$ 

Use channels show to show a list of supported actions.

D-Bus

The service (channels-service.py) exports its objects under the org.semplicelinux.channels BUS_NAME on the System Bus.

Every action namespace has its own object. For example, the channels namespace is located at /org/semplicelinux/channels/channels.
The interface used depend on the namespace. In the channels one, the interface is org.semplicelinux.channels.channels.

For example, to list every available channel:

g7@meddle:~/semplice/channels/channels$ dbus-send --system --dest="org.semplicelinux.channels" --print-reply /org/semplicelinux/channels/channels org.semplicelinux.channels.channels.List
method return sender=:1.1192 -> dest=:1.1193 reply_serial=2
   array [
	  string "jessie"
	  string "sample"
	  string "semplice-current"
	  string "semplice-devel"
	  string "semplice-jessie"
	  string "sid"
   ]
g7@meddle:~/semplice/channels/channels$ 

...and to query the status of one specific channel:

g7@meddle:~/semplice/channels/channels$ dbus-send --system --dest="org.semplicelinux.channels" --print-reply /org/semplicelinux/channels/channels org.semplicelinux.channels.channels.GetEnabled string:"semplice-current"
method return sender=:1.1192 -> dest=:1.1194 reply_serial=2
   boolean true
g7@meddle:~/semplice/channels/channels$ dbus-send --system --dest="org.semplicelinux.channels" --print-reply /org/semplicelinux/channels/channels org.semplicelinux.channels.channels.GetEnabled string:"semplice-jessie"
method return sender=:1.1192 -> dest=:1.1195 reply_serial=2
   boolean false
g7@meddle:~/semplice/channels/channels$