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Hack 94 Use irssi and Its Proxy

irssi is a highly configurable and scriptable
IRC client for Unix. Its proxy feature can open the doors to more
advanced use.

This hack
shows you how to configure the irssi IRC client
and set up its proxy features so you can resume your IRC session
while on the move. irssi can be compiled and
installed from source code or it can be installed from a package.
There are source and package downloads available from the
irssi web site at http://www.irssi.org. If you do compile from
source, make sure you add the --with-proxy option
to configure, as the final part of this hack needs
it. On Debian systems, the package is named
irssi-text. This is because there is an older
version of irssi, which has a graphical
frontend, but it hasn't been maintained for a few
years.

When you start irssi by running the command
irssi, it will print a message telling you to read
some of the documentation. You'll find the
startup-HOWTO on the irssi
web site, although it is also provided in the
docs directory with the
irssi source. You can skip reading it if you
like, as this hack will summarize the important points and walk you
through the process of using the proxy.

irssi supports multiple servers and deals with
connecting to them automatically, but to get the best support, you
really need to define the servers. To do this, you must use the
ircnet and the server commands.
As an example, we'll set up the IRC network freenode
with one server, irc.freenode.net:

/ircnet add  freenode 
/server add -auto -ircnet  freenode irc.freenode.net 

ircnet is the friendly name by which the
connection will be referred to in irssi, but the
server could be one of many. It's possible to add
several servers, so the alternative ones can be tried if there is a
problem connecting to the first. The -auto
parameter to /server means to automatically
connect to this server, and the -ircnet associates
it with the correct IRC network. If you want to add extra information
such as a password for connecting to a server, /help
server will tell you the syntax. The Page Up key should
allow you to scroll up when you are viewing this documentation. The
ircnet command can also accept some options, for
example:

/ircnet add -autosendcmd "/^msg NickServ identify password;wait -freenode
    2000" freenode

This command will automatically message NickServ with your password
and then wait two seconds before trying to join a channel. The
^ character before msg means to
hide the sending of the message so your password
won't be seen by anyone else who happens to be
looking at your screen.

Next you need to decide which channels you want to join. This is very
much the same as with servers, the only real difference being that
the -ircnet parameter has changed:

/channel add -auto  #irchacks freenode 

This means irssi will automatically join
#irchacks when it connects to freenode.

Before you connect, you might like to change your nickname and real
name that are sent to IRCby default, these will be your login
details. They can be changed via the /set command:

/set nick  Nickname 
/set real_name  Real Name 

It's worth noting at this point that the
/set command has a useful feature: if you write
only part of a setting name, it will show all possible settings that
match. The documentation of settings in irssi
isn't brilliant, so this method is a good way to
find undocumented settings. For example, try /set
nick and you will see lots of settings related to
nicknames.

14.10.1 Connecting to a Server

There are two ways you can connect with
irssi. The first is to quit from
irssi (/quit) and start it
again. Because the server is set to automatically connect, it will do
so upon startup. The second way is to type /connect
freenode. Figure 14-9 shows
irssi connected to the freenode IRC network.

Figure 14-9. Using irssi to connect to a server for the first time

Once you have connected and automatically joined a channel,
irssi will have created a new
"window" for the channel. Along the
bottom on the status bar you will see [Act: 2].
This means there is activity in window number 2. You can change
between windows using various keyboard combinations: Alt-number will
change to that window number, Alt-A will change to a window with
activity, and Alt-left arrow and Alt-right arrow will go to the
window to the left and right. If the Alt combination
doesn't work, you will need to change the keyboard
mapping of your terminal. startup-HOWTO has
details about this.

By now, you may have started chatting with the people in the channel
you joined. If you want to ask someone a question or you want to
write something directed at someone, you can type part of her
nickname and press the Tab key. irssi should
complete the nickname and add a colon on the end. Tab completion
doesn't end there though; /
commands will also tab-complete, as will their parameters and even
channel and server names.

If you have joined several channels, you may want to keep them in a
particular order. You can move the current window to the second
location with the /window command:

/window move  2 

Once you have the windows in an order you like, you should run the
command:

/layout save

This will save them and remember the order next time you start
irssi. Another useful feature is split windows.
This means you can display more than one channel at the same time
within the same terminal session. For example, in a channel window,
you can type:

/window show 1

This will show the Status window along the top. You can change to it
with Alt-1 as usual or with Alt-Up.

Connecting to multiple servers with irssi is
very easy. You simply need to define another
ircnet and another set of servers and channel, as
demonstrated by the freenode example earlier.
irssi will then automatically connect to all the
servers on startup. Each server connection is given a tag. This tag
is usually the same as the ircnet, but if you
connect to a server manually or have multiple connections to one
ircnet, it will be different. If you want to
execute a command on a specific server connection, you can add the
-tag parameter to most commands. For example, to
join the channel #foo on the server with the tag private, you would
type:

/join -private #foo

You can also use Ctrl-X to change between servers in a window that
does not have any items, such as the Status window.

The /bind command allows you to change what the
keys do. You can assign them to any command or a few special commands
(see /help bind). By default, the keys Alt-q to
Alt-o (along the top line of a QWERTY keyboard) jump to the windows
11 to 19, but if you have a different keyboard layout, you may want
to change this.

irssi supports embedded Perl scripting.

Perl scripts can control
nearly all the aspects of irssi, so there are
lots of possibilities here if you fancy getting into it. The
irssi script archive at http://irssi.org/scripts has a lot of scripts
available for download. One script will even automatically install
scripts for you from the script archive. To use this, simply type:

/script load scriptassist

If there is a problem loading the script, you may not have the LWP
Perl modules installed. They should be available as a package for
most distributions; the name will be something like
libwww-perl or LWP.

Once scriptassist is loaded, you will see several new script
commands. Typing /script help will give you a
list of all of these.

As an example, if you want to install the title script that sets the
window title in a graphical terminal, type:

/script install title

To run it automatically whenever you start
irssi, type:

/script autorun title

It's also a good idea to do this for scriptassist to
ensure that it is always loaded.

The title script also adds some settings. You can see these by typing:

/set title

Figure 14-10 shows irssi running
in a graphical terminal with the title script. Note that the window
title displays the nickname, network, and current channel.

Figure 14-10. irssi showing scriptassist installing the title script

The status bar at the bottom of the window contains a lot of
information, including your current nickname, channel, or server, as
well as the modes set on them. As mentioned previously, there is an
item that contains the activity in all the windows you have joined.
The window number will change color to white if there are messages in
the channel, or it will turn red if someone has mentioned your
nickname. You can add extra highlight words with the
/hilight command.

It is also possible to script status bar items. For example,
irssi comes with a script called
usercount that will display the number of users
in a channel. To load it, run /script load
usercount. To get the status bar item, you need to use the
/statusbar command. The syntax is a little
confusing, and you need to remember that the first parameter is
always the name of the status bar. You can add the user count to the
right of the status bar on the bottom (the window status bar) with
the following command:

/statusbar window add -alignment right usercount

14.10.2 Using the irssi Proxy

If you're frequently on
the move and end up connecting to IRC from different places,
it's nice to be able to access it from the same
client every time. This not only ensures that you remain permanently
connected to the IRC network, but you will be able to keep all your
log files in one place. irssi allows you achieve
this feat by providing a proxy, which lets you use another IRC client
to connect to your irssi instance.

For those familiar with bouncers (if not, see [Hack #93] ), this is very similar. The
only real difference here is this all happens inside an IRC client,
so if you use irssi inside screen [Hack #92], you don't
always need an IRC client to connect (although you can use one if you
want to).

To load the proxy module, type:

/load proxy

If you want to load the proxy every time you start
irssi, edit the file
~/.irssi/startup, creating it if it
doesn't already exist. You can then add the line
/load proxy to the file, and
this command will be executed automatically every time you start up
irssi.

The proxy module will tell you to set a password when you load it. To
set your password to "password",
you must type:

/set irssiproxy_password password

You will now need to set a port number for each IRC network. These
are the port numbers that you will connect to from another IRC
client. Valid port numbers range from 1024-65535.
It's a good idea to avoid the normal IRC port
(6667), as other people may accidentally connect to you and think
you're running an IRC server.

For example, you may have two IRC networks you want to proxy:
freenode on port 4050 and blitzed on port 4051. Assuming both of
these have been set up correctly with the ircnet
command, you can type:

/set irssiproxy_ports freenode=4050 blitzed=4051

This will enable access to these networks via the proxy.

Now you should be able to use another IRC client to connect to port
4050 of the host where irssi is running. If you
use the correct password, you will appear to join the channels the
irssi client is in. This connection can now be
treated as if you were actually connected to the server, with one
minor differenceyou will see yourself speaking in the other
IRC client when you speak in one.

David Leadbeater