15 Commits

9 changed files with 836 additions and 263 deletions
+26 -8
View File
@@ -1,12 +1,30 @@
all: client server
server_clean:
rm server
re: clean client server
client_clean:
rm client
clean:
rm client.o server.o
client:
go build -o client.o client.go
clean: server_clean client_clean
server:
go build -o server.o server.go
go build server.go
client:
go build client.go
build: server client
ins_server:
go build -o ekho_server server.go
mv ekho_server /usr/local/bin/
cp ekho.service /etc/systemd/system/ekho.service
mkdir -p ~/.config/ekho
ln -s -r ./list.q ~/.config/ekho/list.q
systemctl daemon-reload
systemctl enable ekho
systemctl start ekho
systemctl status ekho
ins_client:
go build -o ekho client.go
mv ekho /usr/local/bin/
+49 -43
View File
@@ -3,80 +3,86 @@
## 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
- Tested with [golang] v1.26
- Installation has only been tested with [just] v1.53
- Server installation assumes systemd (tested with v260.2)
### Installation
Golang can be installed on Mac with
``` sh
brew install golang
```
Clone the repo
``` sh
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.
#### Justfile
It is recommended to use ```just``` for installation, as it has more
capabilities than ```make```, however, there is a makefile included.
To install the server with ```just```, run ```sudo just ins_server```.
You will be prompted to enter a new port number to run the server on (
or leave blank to use 1300). The port will be changed in the source
file before compilation.
To install the client with ```just```, run ```sudo just ins_client```.
You will be prompted to enter the IP (or URL) and port of the server
(or leave blank to use localhost:1300). The IP/URL and port will be
changed in the source file before compilation.
#### Makefile
If you are unable or willing to use ```just```, the included makefile
still has most of the functionality, but it does not change any
important parameters. The following changes are advised before
installation.
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
``` sh
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.
``` sh
make all
```
1. On the client machine, change the IP/URL and port in the client source file. This can be
done quickly with ```sed -i -e "s/127.0.0.1:1300/YOUR.IP.GOES.HERE:PORT/" client.go```
2. On the server machine, change the port in the server source file. This can be done with a
similar command: ```sed -i -e "s/1300/PORT/" server.go```. (note: this
should match the port from bullet 1)
3. On the server machine, change the user referenced in the systemd service file. This can be
done with another sed command, ```sed -e -i "s/USER/YOUR_USERNAME/" ekho.service```
#### 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.
After making these changes on the respective machines, run either
```sudo make ins_client``` or ```sudo make ins_server``` to compile and install the client
and/or server binaries.
For example, if the server used zsh, the installation could look something like this:
``` sh
echo "~/abs/path/to/server.o &" >> ~/.zshrc
```
Similarly for a client using Bash:
``` sh
echo "~/abs/path/to/client.o" >> ~/.bashrc
```
Any help figuring out the issue with MOTD would be appreciated.
#### After Installation
After installation of the server binary, systemd will display the
status of the new service. It should be ```enabled``` and
```running```.
Finally done!
### Usage
The client uses the following flags
``` sh
-h - display help message
-a <s> - adds required argument <s> as a quote to server
-a <string> - adds required argument <s> as a quote to server
-ip <ip:port> - specify alternate server destination
-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
-e [i] - edit; may be run with or without argument
-c - list color format specifiers with examples
-s <i> - specify the size of the receipt buffer
-v - display version and exit
-vv - display version and about info and exit
```
The server uses the following flags
``` sh
-h - display help message
-s - specify the size of the receipt buffer
-s <i> - specify the size of the receipt buffer
-v - display version and exit
-vv - display version and about info and exit
```
### 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][seqdiag] 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
- Request, send, and receive the logfile
- User-specific quotes/quotefiles
- Installation (client-side, at least) via MOTD
[golang]: <https://go.dev/doc/install>
[seqdiag]: <sequencediagram.org>
[just]: <https://github.com/casey/just>
+428 -100
View File
@@ -1,7 +1,7 @@
// =============================================================================
// Auth: alex
// File: client.go
// Revn: 01-09-2025 4.0
// Revn: 09-16-2026 4.0.0
// Func: ask server for a message of the day quote
//
// TODO: remove ioutil import
@@ -24,32 +24,53 @@
// imported check() from soary
// 09-29-2023: commented handle()
//*10-02-2023: commented main(), and friends
//*10-05-2023: /remove/ works
//#10-05-2023: /remove/ works
// removed -d flag
// commented
// 06-12-2024: began added PWFT to /la/
// 06-13-2024: finished adding PWFT to /la/
// commented PWFT stuff
// STARTED BYTE-BASED PWFT REWRITE
//*06-14-2024: finished byte-based PWFT rewrite
//#06-14-2024: finished byte-based PWFT rewrite
// commented
//*01-09-2025: basically just copy/pasted from /la/ into /r1/, /r2/
// 06-21-2026: copied v and vv flags from server
// copied /edit/ switch case from /remove/ in main()
// pulled /sa/ and /qa/ into separate functions
// 09-03-2026: renamed in() -> inputNumber()
// copied in() and removed all logic
// added firstEdit() and secondEdit() and /e1/ and /e2/
// 09-04-2026: rewrote in() with bufio instead of scanln
//#09-06-2026: fixed blank message error in secondEdit()
// comments
// 09-07-2026: added fatih/color import
// rewrote quoteAnswer() to handle coloring escape
// sequences
//*09-12-2026: commented quoteAnswer()
//*09-15-2026: added -c flag and color code example printing
// changed edit command to be add and then remove instead
// of remove and then add, fixing server OOB error when
// editting only quote in list
//#09-15-2026: finished pretty print implementation
// made listAnswer() print list with color print
//
// =============================================================================
package main
import (
"bufio" // NewReader, ReadString
"io" // io.EOF
"io/ioutil" // ReadFile
"flag" // BoolVar, StringVar, Parse
"fmt" // Println
"math/rand" // NewSource, New, Intn, *rand.Rand
"net" // ResolveTCPAddr, DialTCP, conn.Write,Read
"os" // Exit, Create
"os" // Exit, Create, Stdin
"strconv" // Atoi, Itoa
"strings" // Split
"time" // Now, UnixNano
"github.com/fatih/color" // color.New, Printf, Println
)
@@ -85,16 +106,33 @@ func check( err error ) {
// get user input
func in( prompt string ) string {
// instantiate reader
reader := bufio.NewReader( os.Stdin )
fmt.Print( prompt ) // print user prompt
var input string // declare var to hold user input
fmt.Scanln( &input ) // get user input
// get user input, read until newline
input, _ := reader.ReadString( '\n' )
// strip trailing newline before returning
return input[:len( input ) - 1]
}
// get user input, must be a number
func inputNumber( prompt string ) string {
// get user input
//input := in( prompt )
fmt.Print( prompt )
var input string
fmt.Scanln( &input )
// try to convert to an int, discard results
_, err := strconv.Atoi( input )
// if there was an error, user didn't input an int
if err != nil {
// warn user against this
fmt.Println( "Input must be a number" )
input = in( prompt ) // try to get user input again
// try to get user input again
//XXX input = in( prompt )
fmt.Println( "err: ", err.Error() )
// this, like handle() calling handle(), seems like a super
// bad idea, stack-wise...
}
@@ -113,7 +151,7 @@ func seed() *rand.Rand {
// get a random number
func draw() string {
func draw( qsize int ) string {
rn := seed() // get a random seed
r := rn.Intn( qsize ) // get a random number using seed
// convert random number to ascii, because converting
@@ -123,51 +161,135 @@ func draw() string {
}
// get server response and print
func handle( conn net.Conn ) {
// respond to size answer
func sizeAnswer( subcom []string ) string {
// subcom should contain only a size
// convert to int, catch error
size, err := strconv.Atoi( subcom[0] )
// create buffer to hold response
buffer := make( []byte, tsize )
//var buffer [32]byte // create buffer to hold response
// read n bytes from server into buffer ( byte slice )
n, err := conn.Read( buffer[:] )
check( err ) // check for errors
// split recv'd message over @, separate header from message
msg := strings.Split( string( buffer[:n] ), "@" )
var resp string // declare response variable
switch msg[0] { // switch/case over the header
// if message is...
case "sa": // /sa/, size answer
// convert back half to int, catch error
size, nerr := strconv.Atoi( msg[1] )
if nerr == nil { // if there was no error
qsize = size // set size global to recv'd size
} else {
// if int conversion failed, just quit
// TODO make more robust
os.Exit( 1 )
if err != nil { // if int conversion failed ( for some reason )
os.Exit( 1 ) // just quit
// TODO make exit codes unique, document them
}
req := draw() // draw a random number
resp = "qr@" + req // create quote query with rng
case "ba": // /ba/, bad answer
// TODO create server-side, and handle client-side
fmt.Println( "error in " + msg[1] + ": " + msg[2] )
resp = "te@error" // set transaction end message
case "qa": // /qa/, quote answer
fmt.Println( msg[1] ) // whole-ass just print quote
resp = "te@success" // set transaction end message
case "la": // /la/, list answer
if len( msg ) > 2 { // multistage send condition
if msg[1] == "X" { // final message
// draw a random number, add to quote request
return "qr@" + draw( size )
}
// receive quote, print
func quoteAnswer( subcom []string ) string {
// split subcommand over spaces
words := strings.Split( subcom[0], " " )
// default text is white
c := color.New( color.FgWhite )
for _, w := range words {
// if first char is normal color escape character
if string( w[0] ) == "$" {
// see which color is requested
switch string( w[1] ) {
case "1": // 1 -> red
c = color.New( color.FgRed )
case "2": // 2 -> yellow
c = color.New( color.FgYellow )
case "3": // 3 -> green
c = color.New( color.FgGreen )
case "4": // 4 -> blue
c = color.New( color.FgBlue )
case "5": // 5 -> cyan
c = color.New( color.FgCyan )
case "6": // 6 -> magenta
c = color.New( color.FgMagenta )
case "7": // 7 -> black
c = color.New( color.FgBlack )
case "0": // 0 -> white again
c = color.New( color.FgWhite )
default:
// none of these, continue with the last color
}
// color chosen, print string with trailing space, minus
// first two characters
c.Printf( "%s ", w[2:] )
// if first char is bold color escape character
} else if string( w[0] ) == "#" {
// see which color is requested
switch string( w[1] ) {
case "1": // 1 -> red
c = color.New( color.FgRed, color.Bold )
case "2": // 2 -> yellow
c = color.New( color.FgYellow, color.Bold )
case "3": // 3 -> green
c = color.New( color.FgGreen, color.Bold )
case "4": // 4 -> blue
c = color.New( color.FgBlue, color.Bold )
case "5": // 5 -> cyan
c = color.New( color.FgCyan, color.Bold )
case "6": // 6 -> magenta
c = color.New( color.FgMagenta, color.Bold )
case "7": // 7 -> black
c = color.New( color.FgBlack, color.Bold )
case "0": // 0 -> white again
c = color.New( color.FgWhite, color.Bold )
default:
// none of these, continue with the last color
}
// color chosen, print string with trailing space, minus
// first two characters
c.Printf( "%s ", w[2:] )
} else { // TODO add if for if w[0] is "\"
// using the currently selected color, print the next work
// and a trailing space
c.Printf( "%s ", w )
}
}
c.Println() // print final newline
//fmt.Println( subcom[0] ) // whole-ass just print quote
return "te@success" // set transaction end message
}
// add answer
func addAnswer( subcom []string ) string {
var resp string = "te@"
// if server says add succeeded
if subcom[0] == "success" {
fmt.Println( "Add successful" ) // print success
resp = resp + "success" // set transaction end message
// if server says add failed
} else if subcom[0] == "error" {
fmt.Println( "Add failed" ) // print fail
resp = resp + "error" // set transaction end message
// unknown status message
} else {
// print unknown status
fmt.Println( "Unknown status code: " + subcom[0] )
// TODO should this be unknown instead of error?
resp = resp + "error" // set transaction end message
}
return resp
}
// receive answer to list
func listAnswer( subcom []string ) string {
var resp string
if len( subcom ) > 1 { // multistage send condition
if subcom[0] == "X" { // final message
// TODO update
// read entire temp storage file as byte array
tfile, err := ioutil.ReadFile( "temp.q" )
check( err ) // check read for errors
// cast file to string, concat with recv'd string
tstr := string( tfile ) + msg[2]
tstr := string( tfile ) + subcom[1]
// split concat over newlines, separating quotes
tlist := strings.Split( tstr, "\n" )
// iterate over array, printing each quote
@@ -186,57 +308,42 @@ func handle( conn net.Conn ) {
check( err ) // check file open for errors
// write received message to file, keeping track
// of bytes written
n, err = f.WriteString( msg[2] )
n, err := f.WriteString( subcom[1] )
check( err ) // check file write for errors
// cast bytes already written field to int
b, err := strconv.Atoi( msg[1] )
b, err := strconv.Atoi( subcom[0] )
check( err ) // check cast for errors
// add bytes just written to bytes already
// written, cast back to string, and append to
// response variable
// add bytes just written to bytes already written, cast
// back to string, and append to response variable
resp = "lr@" + strconv.Itoa( b + n )
}
} else {
// split recv'd message over \n, create quote list
quotes := strings.Split( msg[1], "\n" )
quotes := strings.Split( subcom[0], "\n" )
for p, v := range quotes { // iterate over quotes
// print num of quote, followed by that quote
fmt.Println( p + 1, "\t", v )
fmt.Print( p + 1, "\t" )
quoteAnswer( []string{ v } )
}
resp = "te@success" // set transaction end message
}
case "aa": // /aa/, add answer
// if server says add succeeded
if msg[1] == "success" {
fmt.Println( "Add successful" ) // print success
resp = "te@success" // set transaction end message
// if server says add failed
} else if msg[1] == "error" {
fmt.Println( "Add failed" ) // print fail
resp = "te@error" // set transaction end message
// unknown status message
} else {
// print unknown status
fmt.Println( "Unknown status code: " + msg[1] )
// TODO should this be unknown instead of error?
resp = "te@error" // set transaction end message
return resp
}
case "r1": // /r1/, remove ( first transaction )
// the idea is that if the user doesn't specify which quote to
// remove, list all quotes and let the user choose the quote
// to remove. There was probably a way to handle this a little
// more simply, but this, I feel, has some nuance to it that I
// actually like
// redo /r1/, list all quotes
// split recv'd message over newline to create quote list
if len( msg ) > 2 { // multistage send condition
if msg[1] == "X" { // final message
// first round edit request
func firstEdit( subcom []string ) string {
var resp string
if len( subcom ) > 1 { // multistage send condition
if subcom[0] == "X" { // final message
// TODO update
// read entire temp storage file as byte array
tfile, err := ioutil.ReadFile( "temp.q" )
check( err ) // check read for errors
// cast file to string, concat with recv'd string
tstr := string( tfile ) + msg[2]
tstr := string( tfile ) + subcom[1]
// split concat over newlines, separating quotes
tlist := strings.Split( tstr, "\n" )
// iterate over array, printing each quote
@@ -247,7 +354,7 @@ func handle( conn net.Conn ) {
err = os.Remove( "temp.q" )
check( err ) // check rm for errors
// ask user which quote to remove
resp = "r2@" + in( "\n-> " )
resp = "e2@" + inputNumber( "\n-> " )
} else { // first or intermediate message
// open temp quote storage file, creating if
// necessary, with write-only permissions, in
@@ -256,55 +363,185 @@ func handle( conn net.Conn ) {
check( err ) // check file open for errors
// write received message to file, keeping track
// of bytes written
n, err = f.WriteString( msg[2] )
n, err := f.WriteString( subcom[1] )
check( err ) // check file write for errors
// cast bytes already written field to int
b, err := strconv.Atoi( msg[1] )
b, err := strconv.Atoi( subcom[0] )
check( err ) // check cast for errors
// add bytes just written to bytes already
// written, cast back to string, and append to
// response variable
// add bytes just written to bytes already written, cast
// back to string, and append to response variable
resp = "e1@" + strconv.Itoa( b + n )
}
} else {
// split recv'd message over \n, create quote list
quotes := strings.Split( subcom[0], "\n" )
for p, v := range quotes { // iterate over quotes
// print num of quote, followed by that quote
fmt.Println( p + 1, "\t", v )
}
// ask user which quote to edit
resp = "e2@" + inputNumber( "\n-> " )
}
return resp
}
// second round edit request ( and also third, technically )
func secondEdit( subcom []string ) string {
// success message and edit request pt2 come to the same place
if subcom[0] == "success" {
// print success and end transaction
fmt.Println( "Edit successful" )
return "te@success"
}
// edit command is an add and then a removal
var resp string
resp = "cr@ar@"
fmt.Println( "as is: " + subcom[1] )
fmt.Print( "preview: " ) // show raw of current quote
_ = quoteAnswer( subcom[1:] ) // display quote properly
// server response is user input for new quote
resp = resp + in( "\nupdate -> " )
// and position of old quote to be removed
resp = resp + "@r2@" + subcom[0]
return resp
}
// list of all quotes, pick which to remove
func firstRemove( subcom []string ) string {
// the idea is that if the user doesn't specify which quote to
// remove, list all quotes and let the user choose the quote
// to remove. There was probably a way to handle this a little
// more simply, but this, I feel, has some nuance to it that I
// actually like
var resp string
if len( subcom ) > 1 { // multistage send condition
if subcom[0] == "X" { // final message
// TODO update
// read entire temp storage file as byte array
tfile, err := ioutil.ReadFile( "temp.q" )
check( err ) // check read for errors
// cast file to string, concat with recv'd string
tstr := string( tfile ) + subcom[1]
// split concat over newlines, separating quotes
tlist := strings.Split( tstr, "\n" )
// iterate over array, printing each quote
for p, v := range tlist {
fmt.Println( p + 1, "\t", v )
}
// delete temp storage file
err = os.Remove( "temp.q" )
check( err ) // check rm for errors
// ask user which quote to remove
resp = "r2@" + inputNumber( "\n-> " )
} else { // first or intermediate message
// open temp quote storage file, creating if
// necessary, with write-only permissions, in
// append mode, wr u perm, r g/w perm
f, err := os.OpenFile( "temp.q", os.O_WRONLY | os.O_APPEND | os.O_CREATE, 0644 )
check( err ) // check file open for errors
// write received message to file, keeping track
// of bytes written
n, err := f.WriteString( subcom[1] )
check( err ) // check file write for errors
// cast bytes already written field to int
b, err := strconv.Atoi( subcom[0] )
check( err ) // check cast for errors
// add bytes just written to bytes already written, cast
// back to string, and append to response variable
resp = "r1@" + strconv.Itoa( b + n )
}
} else {
// split recv'd message over \n, create quote list
quotes := strings.Split( msg[1], "\n" )
quotes := strings.Split( subcom[0], "\n" )
for p, v := range quotes { // iterate over quotes
// print num of quote, followed by that quote
fmt.Println( p + 1, "\t", v )
}
// ask user which quote to remove
resp = "r2@" + in( "\n-> " )
resp = "r2@" + inputNumber( "\n-> " )
}
case "r2": // /r2/, remove ( second transaction )
return resp
}
// second remove, determine if success or failure
func secondRemove( subcom []string ) string {
var resp string
// if server says remove succeeded
if msg[1] == "success" {
if subcom[0] == "success" {
fmt.Println( "Remove successful\n" ) // success
// list all quotes to validate remove succeeded
// TODO should /aa/ also make /lr/ before /te/?
resp = "lr@init" // set transaction end message
// if server says remove failed
} else if msg[1] == "error" {
} else if subcom[0] == "error" { // if server says remove failed
fmt.Println( "Remove failed" ) // print failure
resp = "te@error" // set transaction end message
// if unknown status message
} else {
} else { // if unknown status message
// TODO there's a known issue where if the buffer
// size ( -s ) is less than 10, on the server side,
// 'success' will get cut off ( r2@success )
// and /r2/ will end up down here despite having
// actually worked correctly, and with not display the
// actually worked correctly, and will not display the
// list, as it should on success
// print unknown status
fmt.Println( "Unknown error code: " + msg[1] )
fmt.Println( "Unknown error code: " + subcom[0] )
// TODO should this be unknown instead of error?
resp = "te@error" // set transaction end message
}
return resp
}
// get server response and print
func handle( conn net.Conn ) {
// create buffer to hold response
buffer := make( []byte, tsize )
//var buffer [32]byte // create buffer to hold response
// read n bytes from server into buffer ( byte slice )
n, err := conn.Read( buffer[:] )
check( err ) // check for errors
// split recv'd message over @, separate header from message
message := strings.Split( string( buffer[:n] ), "@" )
command := message[0]
var resp string // declare response variable
switch command { // switch/case over the header
// if message is...
case "sa": // /sa/, size answer
resp = sizeAnswer( message[1:] )
case "qa": // /qa/, quote answer
resp = quoteAnswer( message[1:] )
case "aa": // /aa/, add answer
resp = addAnswer( message[1:] )
case "la": // /la/, list answer
resp = listAnswer( message[1:] )
case "e1": // /e1/, edit quote ( first transaction )
resp = firstEdit( message[1:] )
case "e2": // /e2/, edit quote ( second transaction )
resp = secondEdit( message[1:] )
case "r1": // /r1/, remove ( first transaction )
resp = firstRemove( message[1:] )
case "r2": // /r2/, remove ( second transaction )
resp = secondRemove( message[1:] )
case "br": // /br/, bad request
// client has asked for something nonsensical
// TODO write out to file
fmt.Println( "Client sent a bad request" )
resp = "te@error" // set transaction end message
case "ba": // /ba/, bad answer
// TODO create server-side, and handle client-side
fmt.Println( "error in " + message[1] + ": " + message[2] )
resp = "te@error" // set transaction end message
default: // something undefined entirely
// TODO write out to file
//fmt.Println( "Message header not recognized" )
@@ -322,26 +559,97 @@ func handle( conn net.Conn ) {
// globals
var qsize int // keep track of num of quotes
//var qsize int // keep track of num of quotes
var conn net.Conn // keep track of connection
// global flag variables
var add bool // add new quotes to quote file ( on server )
var remove bool // remove quotes from quote file ( on server )
var list bool // request entire quote file from server
var edit bool // edit a pre-existing quote from quote file ( on server )
var co bool // list color codes
var dest string // provide a new destination ip and port
var tsize int // size of transmission buffer
var VERS string // version
func main() {
var v bool // version flag
var vv bool // big version flag
// define flags
flag.BoolVar( &add, "a", false, "add quote to list" )
flag.BoolVar( &remove, "r", false, "remove quote from list" )
flag.BoolVar( &list, "l", false, "print quote list" )
flag.StringVar( &dest, "ip", ":1300", "ip:port of server" )
flag.BoolVar( &edit, "e", false, "edit quote from list" )
flag.BoolVar( &co, "c", false, "list color codes with examples" )
flag.StringVar( &dest, "ip", "127.0.0.1:1300", "ip:port of server" )
flag.IntVar( &tsize, "s", 256, "transmission size ( bytes )" )
flag.Parse() // process flags
flag.BoolVar( &v, "v", false, "display version and exit" )
flag.BoolVar( &vv, "vv", false, "display version and about info and exit" )
flag.Parse()
// FIXME get better versioning method
VERS = "4.0.0"
if vv { // display info and exit
fmt.Println( "ekho client v" + VERS )
fmt.Println( "ekho is named after Echo the Oread" )
fmt.Println( "in Greek mythology, Echo was cursed by Hera to only be able to say the last words spoken to her" )
fmt.Println( "i found this to be quite fitting for a MOTD server" )
return
} else if v { // display info and exit
fmt.Println( VERS )
return
}
if co { // display color codes and examples and quit
// print color code and color example on same line
// color.XYZ print inserts newline
fmt.Print( "$1: " )
color.Red( "red" )
fmt.Print( "$2: " )
color.Yellow( "yellow" )
fmt.Print( "$3: " )
color.Green( "green" )
fmt.Print( "$4: " )
color.Blue( "blue" )
fmt.Print( "$5: " )
color.Cyan( "cyan" )
fmt.Print( "$6: " )
color.Magenta( "magenta" )
fmt.Print( "$7: " )
color.Black( "black" )
fmt.Print( "$0: " )
color.White( "white (reset)" )
// print bold codes
fmt.Print( "\n#1: " )
// create bold color object, change out actual color and print
bold := color.New( color.Bold, color.FgRed )
bold.Println( "bold red" )
fmt.Print( "#2: " )
bold.Add( color.FgYellow )
bold.Println( "bold yellow" )
fmt.Print( "#3: " )
bold.Add( color.FgGreen )
bold.Println( "bold green" )
fmt.Print( "#4: " )
bold.Add( color.FgBlue )
bold.Println( "bold blue" )
fmt.Print( "#5: " )
bold.Add( color.FgCyan )
bold.Println( "bold Cyan" )
fmt.Print( "#6: " )
bold.Add( color.FgMagenta )
bold.Println( "bold magenta" )
fmt.Print( "#7: " )
bold.Add( color.FgBlack )
bold.Println( "bold black" )
fmt.Print( "#0: " )
bold.Add( color.FgWhite )
bold.Println( "bold white" )
return // bail
}
service := dest // declare server ip:port
@@ -375,6 +683,27 @@ func main() {
fmt.Println( "/a/ flag must be used with an arugment" )
os.Exit( 1 )
}
case edit: // if edit flag is active
// if arguments were specified
if len( flag.Args() ) > 0 {
// argument is supposed to the number of the quote to
// be edited, get first arg
// cast to int just to make sure it's a valid number
// assuming the user knows what they're doing
_, rerr := strconv.Atoi( flag.Args()[0] )
// if there was an error, just pretend there's no args
if rerr != nil {
command = "e1@init" // remove request 1
} else {
// if user knows the number, take care of it
// arg[0] is a string, so concat is cool
// jump right into edit request 2
command = "e2@" + flag.Args()[0]
}
} else { // if no argument was specified for edit
// jump right into edit request 1
command = "e1@init"
}
case remove: // if remove flag is active
// if arguments were specified
if len( flag.Args() ) > 0 {
@@ -386,7 +715,6 @@ func main() {
// if there was an error, just pretend there's no args
if rerr != nil {
command = "r1@init" // remove request 1
// TODO come up w/ useful argument, replace dumvar
} else {
// if user knows the number, take care of it
// arg[0] is a string, so concat is cool
+14
View File
@@ -0,0 +1,14 @@
[Unit]
Description=Ekho MOTD Server
After=network.target
[Service]
Type=simple
Restart=always
RestartSec=5
User=USER
ExecStart=/usr/local/bin/ekho_server
WorkingDirectory=/home/USER/.config/ekho
[Install]
WantedBy=multi-user.target
+11
View File
@@ -0,0 +1,11 @@
module earth-1.net/oracle/ekho
go 1.27.1
require github.com/fatih/color v1.19.0
require (
github.com/mattn/go-colorable v0.1.14 // indirect
github.com/mattn/go-isatty v0.0.20 // indirect
golang.org/x/sys v0.42.0 // indirect
)
+9
View File
@@ -0,0 +1,9 @@
github.com/fatih/color v1.19.0 h1:Zp3PiM21/9Ld6FzSKyL5c/BULoe/ONr9KlbYVOfG8+w=
github.com/fatih/color v1.19.0/go.mod h1:zNk67I0ZUT1bEGsSGyCZYZNrHuTkJJB+r6Q9VuMi0LE=
github.com/mattn/go-colorable v0.1.14 h1:9A9LHSqF/7dyVVX6g0U9cwm9pG3kP9gSzcuIPHPsaIE=
github.com/mattn/go-colorable v0.1.14/go.mod h1:6LmQG8QLFO4G5z1gPvYEzlUgJ2wF+stgPZH1UqBm1s8=
github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/sys v0.42.0 h1:omrd2nAlyT5ESRdCLYdm3+fMfNFE/+Rf4bDIQImRJeo=
golang.org/x/sys v0.42.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+69
View File
@@ -0,0 +1,69 @@
# delete server bin
[private]
server_clean:
rm server
# delete client bin
[private]
client_clean:
rm client
# delete binaries
clean: server_clean client_clean
# build server bin
server:
go build server.go
# build client bin
client:
go build client.go
# build both bins
build: client server
# delete binaries and make them again
rebuild: clean build
# install server
ins_server:
#!/usr/bin/bash
echo "enter port of server or leave blank to use default (1300)"
read PORT
if [[ $PORT -ne "" ]]; then
sed -i -e "s/1300/$PORT/" server.go
fi
echo "go build -o ekho_server server.go"
go build -o ekho_server server.go
echo "mv ekho_server /usr/local/bin/"
mv ekho_server /usr/local/bin/
USER=($(users))
sed -i -e "s/USER/${USER[0]}/" ekho.service
echo "cp ekho.service /etc/systemd/system/"
cp ekho.service /etc/systemd/system/
mkdir -p ~/.config/ekho
echo "ln -s -r ./list.q ~/.config/ekho/list.q"
ln -s -r ./list.q ~/.config/ekho/list.q
echo "systemctl daemon-reload"
systemctl daemon-reload
echo "systemctl enable ekho"
systemctl enable ekho
echo "systemctl start ekho"
systemctl start ekho
echo "systemctl status ekho"
systemctl status ekho
# install client
ins_client:
#!/usr/bin/bash
echo "enter url or ip and port of server, 'aaa.bbb.ccc.ddd:port"
read IP_PORT
sed -i -e "s/:1300/$IP_PORT/" client.go
echo "go build -o ekho client.go"
go build -o ekho client.go
sed -i -e "s/$IP_PORT/:1300/" client.go
echo "mv ekho /usr/local/bin/"
mv ekho /usr/local/bin/
echo "add 'ekho' to shell config (config.fish, .bashrc, etc)"
+1 -1
View File
@@ -1 +1 @@
thank you for using ekho
thank you for using $1ekho
+139 -21
View File
@@ -1,14 +1,15 @@
// =============================================================================
// Auth: alex
// File: server.go
// Revn: 01-09-2025 5.0
// Revn: 09-15-2026 3.0.2
// Func: host MOTD connection
//
// TODO: remove ioutil import
// add more /codes/ to handle
// add flags, like specify port
// TODO: add user-specific prints
// write usage and errors to logfile
// remove ioutil import
// send logfile to client on request
// add flags?
// add more /codes/ to handle
// =============================================================================
// CHANGE LOG
// -----------------------------------------------------------------------------
@@ -31,7 +32,7 @@
// fixed bug in /r2/ where removing quote at final
// position would break
// removed deadcode from /r2/, unused "quit" bool?
//*10-17-2023: fixed bug where quotes are read from and saved to two
//#10-17-2023: fixed bug where quotes are read from and saved to two
// different files
// removed implicit newline at end of qfile to stop ghost
// line bug in /la/
@@ -43,7 +44,16 @@
// commented
//*06-14-2024: byte count-based PWFT rewrite
//*06-17-2024: catch keyboard interrupts with os/signal and syscall
//*01-09-2025: copied lr/la PWFT updates into r1/r2
//#01-09-2025: copied lr/la PWFT updates into r1/r2
//*04-28-2026: removed implicit newline at end of qfile to stop ghost
// line bug in /la/ AGAIN
// 05-11-2026: updated fread() to handle users in qfile
// 05-12-2026: added v and vv input flags
// 09-05-2026: buncha shit happened, dropped the commit
//#09-06-2026: added /e1/, /e2/, and /cr/, got edit working
// 09-12-2026: minor comments in receive()
//*09-15-2026: fixed OOB error in /qa/ for perhaps the last time
// fixed bad Atoi conversion bug for perhaps the last time
//
// =============================================================================
@@ -114,10 +124,10 @@ func fread() string {
// bugs where a blank item was introduced into qlist and calling
// /la/ would produce a blank line on the client side that didn't
// really exist
//qfile = qfile[:len( qfile ) - 1]
qfile = qfile[:len( qfile )]
// cast bytes to string, split string over newline into array
qlist = strings.Split( string( qfile ), "\n" )
// deal with the trailing
return string( qfile ) // return file as string
}
@@ -133,8 +143,8 @@ func writeFile( f string ) {
}
// handle connections ( new and improved )
func handle( conn net.Conn ) {
// receive from connection, send to get processed, send out response
func receive( conn net.Conn ) {
// create buffer to hold read message
buffer := make( []byte, tsize )
@@ -146,6 +156,26 @@ func handle( conn net.Conn ) {
// cast message to string, take first n bytes, split over @
command := strings.Split( string( buffer[:n] ), "@" )
// if command is to end transaction
if command[0] == "te" {
conn.Close() // end transaction
return // and bail
}
// process command get response
resp := handle( command )
// write response to client
_, err = conn.Write( []byte( resp ) )
checkN( err, conn ) // make sure write worked
receive( conn ) // call handle() again to get response from client
}
// handle connections ( new and improved )
func handle( command []string ) string {
// declare response string
var resp string
switch command[0] { // switch/case over opcode
@@ -223,6 +253,78 @@ func handle( conn net.Conn ) {
qfile = qfile + "\n" + command[1]
writeFile( qfile )
resp = "aa@success" // add answer
case "cr":
if len( command ) != 5 {
return "ba@bad request"
}
//mes1 := strings.Join( command[1:3], "@" )
//mes1 := strings.Join( command[3:], "@" )
_ = handle( command[1:3] )
_ = handle( command[3:] )
resp = "e2@success"
case "e1":
resp = "e1@" // begin crafting response
// file too big for single transmission
// initial header size is 5, e1@1@, so counting that into
// the transmission size, the file must be longer than 251
// ( default ) bytes to reach this block of code
if len( qfile ) > ( tsize - 5 ) {
if command[1] == "init" { // first request
// add message number, delim, and the first
// transmittable bytes
resp = resp + "0@" + qfile[:( tsize - 5 )]
} else { // subsequent requests
// convert byte count to int
bytes, err := strconv.Atoi( command[1] )
check( err ) // make sure convert worked
// replace tx'd bytes and delim to new header
resp = resp + command[1] + "@"
rlen := len( resp ) // capture header length
// slices are always of size "txsize - header
// length", so find end byte
end := bytes + ( tsize - rlen )
// if end goes beyond the bounds of the list
if end > len( qfile ) {
// replace byte count with X to signal
// final message, concat the rest of the file,
// beginning with the start index
resp = "e1@X@" + qfile[bytes:]
} else {
// get slice from start index to end, concat
// with response
resp = resp + qfile[bytes:end]
}
}
} else { // file is smaller than the tx size
// just concat entire list to send
resp = resp + qfile // list answer
}
case "e2":
// convert message argument to string to make sure it's a
// valid number
num, nerr := strconv.Atoi( command[1] )
// nerr will not be nil if comm[1] is not a number
if nerr != nil {
// formulate an error message
// TODO flesh this out more
resp = "ba@qr@!" // bad answer
} else { // comm[1] was a number, but...
switch { // how do we know it's a valid number
case num > len( qlist ):
// bad answer in quote request
resp = "ba@qr@>"
// why bad? num is >
case num < 0:
// bad answer in quote request
resp = "ba@qr@-"
// why bad? num is -
default:
// good num, get quote, send off
resp = "e2@" + command[1] + "@" + qlist[num - 1]
}
}
case "r1": // /r1/, remove request 1
resp = "r1@" // begin crafting response
// file too big for single transmission
@@ -315,18 +417,14 @@ func handle( conn net.Conn ) {
case "te": // /te/, transaction end
// TODO should I be sending something?
// TODO is it better to close now or outside of handle()
conn.Close() // close connection and leave
return // return from handle(), finish connection
//conn.Close() // close connection and leave
return "" // return from handle(), finish connection
default: // opcode not recognized
// TODO there should be more being down, here, right?
return // return from handle(), finish connection
return "" // return from handle(), finish connection
}
// write response to client
_, err = conn.Write( []byte( resp ) )
checkN( err, conn ) // make sure write worked
handle( conn ) // call handle() again to get response from client
return resp
}
@@ -335,7 +433,7 @@ func handle( conn net.Conn ) {
var qlist []string // list of quotes
var qfile string // file object
var tsize int // size of transmission buffer
var VERS string // version
// main, create port and wait for connection
func main() {
@@ -345,12 +443,32 @@ func main() {
// set interrupt and terminate signals to notify channel
signal.Notify( sigs, syscall.SIGINT, syscall.SIGTERM )
// flag vars
var v bool // simple version
var vv bool // verbose version
// flag for default transmission size
flag.IntVar( &tsize, "s", 256, "transmission size ( bytes )" )
flag.BoolVar( &v, "v", false, "display version and exit" )
flag.BoolVar( &vv, "vv", false, "display version and about info and exit" )
flag.Parse()
qfile = fread() // read quote file, init ( global ) list of quotes
// FIXME get better versioning method
VERS = "3.0.2"
if vv { // display info and exit
fmt.Println( "ekho server v" + VERS )
fmt.Println( "ekho is named after Echo the Oread" )
fmt.Println( "in Greek mythology, Echo was cursed by Hera to only be able to say the last words spoken to her" )
fmt.Println( "i found this to be quite fitting for a MOTD server" )
return
} else if v { // display info and exit
fmt.Println( VERS )
return
}
qfile = fread() // read quote file, init ( global ) list of quotes
service := ":1300" // create service on ip and port
// resolve ip address and port
@@ -372,7 +490,7 @@ func main() {
// wait, create connection when found
conn, err := listener.Accept()
check( err ) // make sure connection works
go handle( conn ) // handle connection
go receive( conn ) // handle connection
}
}