ekho

Needlessly Networked MOTD generator

Why?

To test my abilities to develop networked programs, and to enhance my skills in writing such.

Requirements

Hardware

• Client machine
• Server machine (not required to be distinct from Client)

Software

• Golang
• Linux distro (highly recommened)
• make is also used in this guide, but the makefile is incredibly simple, and can be skipped entirely by running go build instead

Installation

Golang can be installed on Mac with

brew install golang

Clone the repo

git clone https://github.com/alexander-the-alright/ekho
cd ekho

Using your favorite text editor, change the destination IP and Port to whatever works for you. This is defined on line 247 in client.go as 127.0.0.1:1300.

Now the server file needs to be run on the preferred port, as specified in the client file. This is defined on line 257 in server.go.

The binary(s) can be obtained using the makefile If the server is being run on a separate machine, only run make with client flag

make client

If both binaries are being run on the same machine, make all will suffice. Although, both of these commands can be bypassed with go build, as this is all make does anyway.

make all

NOTE

In previous versions, the suggested method of installation involved placing bash scripts in /etc/update-motd.d/, however, there have been issues getting that installation method working (namely, having MOTD run user-defined commands), and the current quick and extremely dirty suggested installation method is to just append the user's shell config files (.bashrc, .bash_profile, .zshrc, etc) with the paths to the executables.

For example, if the server used zsh, the installation could look something like this:

echo "~/abs/path/to/server.o &" >> ~/.zshrc

Similarly for a client using Bash:

echo "~/abs/path/to/client.o" >> ~/.bashrc

Any help figuring out the issue with MOTD would be appreciated.

Finally done!

Usage

The client uses the following flags

-h      - display help message
-a <s>  - adds required argument <s> as a quote to server
-l      - list all quotes
-r [i]  - remove; may be run with or without argument
-ip     - specify alternate server destination
-s      - specify the size of the receipt buffer

The server uses the following flags

-h      - display help message
-s      - specify the size of the receipt buffer

How It Works

The sequence diagram can be viewed in diag folder, which shows the sequence of networked messages for each usage of ekho. The source code is in the same folder, ekho-seq.txt, and can be uploaded to sequencediagram.org to rerender the diagram and view any updates.

To Be Implemented

• Log all uses/transaction data each day
• Request, send, and receive the logfile for any day
• User-specific quotes/quotefiles
• Installation (client-side, at least) via MOTD