kfclient

A simple boost::asio based Killing Floor 2 server query protocol client

libkfclient

This is the main library in the project providing functionality for all the interaction with the Killing Floor 2 Query Port protocol (usually at port 27015). This library will use boost::asio to connect to the desired Killing Floor 2 server's query service and it will allow the user of the library to fetch server details, rules and player lists. The library was developed for a private project regarding KF2 server management.

kfclient-cli

This is the commandline utility that exposes the libkfclient API to the terminal. This simple tool can be used to obtain a player count or display the details, rules and the players currently on a server. This tool is useful to schedule server updates at times when there are no players currently online. This way, we can schedule a daily update without disrupting playtime.

lkfclient

This is the Lua 5.3 binding to libkfclient, providing all the functionality from the library to a Lua environment. The CMakeLists.txt and source code in this subdir can be easily modified to support Lua 5.4 if needed.

Dependencies

entity	dependencies	versions
all	libboost_system	1.45
	Threads::Threads	(pthread preferred)
kfclient-cli	fmt	any recent version
	CLI11	any recent version
	libfort	any recent version
lkfclient	Lua 5.3 (liblua5.3-dev lua5.3)	5.3

The boost and fmt dependencies can be installed on many debian based systems, however all of these dependencies can be built and installed as per their own instructions by using their shipped CMakeLists with the exception of Lua. Lua 5.3 can be installed on debian systems, but can be built from source available at lua.org.

Building

When all dependencies are available on the build system, building all entities is really straightforward. Create a build directory anywhere on the system and cd into it. Then invoke cmake:

cmake -DCMAKE_BUILD_TYPE=Release [path_to_kfclient_repository]
cmake --build . --config Release

Installing

Using cmake, this should also be very straightforward. In the same directory that was used to build kfclient in:

sudo cmake --install .

Using the kfclient-cli application

Assuming it was built and installed, using the kfclient-cli application is quite simple. There are not many options to choose from, when you view kfclient --help you'll get the following output:

a very simple command line utility that implements libkfclient for obtaining information about Killing Floor 2 servers
Usage: kfclient [OPTIONS] host [port]

Positionals:
  host TEXT REQUIRED          the host of the Killing Floor 2 server to connect to.
  port UINT=27015             the port on [host] on which the Killing Floor 2 server can be polled for information. By default, this is 27015

Options:
  -h,--help                   Print this help message and exit
  -H,--help-all               show all help.
  -V,--verbose                output more information.
  -c,--clean-tables           output tables without borders.
  -P,--player-count           output the player count and nothing else
  -r,--report TEXT:{details,rules,players,d,r,p} ...
                              report a category of information (details, rules, players)
  -t,--timeout UINT=10        the timeout for datagram operations.
  -v,--version                display the version of kfclient.

Warning: the timeout option has not been implemented yet.

Dumping server information

If you would like to display the details, rules and players on a server localhost at the default port 27015:

kfclient -rd -rr -rp localhost

Or without formatted tables:

kfclient -c -rd -rr -rp localhost 

Or you want to get the player count on server localhost at port 27016:

kfclient -P localhost 27016 | cut -d ':' -f2 | tr -d ' '

Using the Lua library

Upon a successful build and install, a Lua library interfacing with libkfclient is also installed to the system. The path is /usr/local/lib/lua/5.3/kfclient.so. You might have to reconfigure ldd or specify LD_LIBRARY_PATH to include this directory on your to ensure that Lua can find it.

Simple example:

local kfc = require "kfclient";
local client = kfc.open("localhost", 27015);  -- use pcall to catch errors 
local tbl_details = client:details();         -- associative table
local tbl_rules = client:rules();             -- associative table
local tbl_players = client:players();         -- sequential table of associative tables 
client:close();                               -- terminate connection

for name, value in pairs(tbl_details) do 
  print(name, value);
end 

for rule, value in pairs(tbl_rules) do 
  print(rule, type(value), value);
end 

for _, player in ipairs(tbl_players) do 
  print(player.id, player.name, player.score, player.time);
end