4 Commits

7 changed files with 689 additions and 253 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: clean: server_clean client_clean
rm client.o server.o
client:
go build -o client.o client.go
server: 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/
+50 -46
View File
@@ -3,80 +3,84 @@
## Why? ## Why?
To test my abilities to develop networked programs, and to enhance my skills in writing such. To test my abilities to develop networked programs, and to enhance my skills in writing such.
## Requirements ## Requirements
### Hardware ### Hardware
- Client machine - Client machine
- Server machine (not required to be distinct from Client) - Server machine (not required to be distinct from Client)
### Software ### Software
- [Golang] - Tested with [golang] v1.26
- Linux distro (highly recommened) - Installation has only been tested with [just] v1.53
- ```make``` is also used in this guide, but the makefile is incredibly simple, and can be skipped entirely by running ```go build``` instead - Server installation assumes systemd (tested with v260.2)
### Installation ### Installation
Golang can be installed on Mac with
``` sh
brew install golang
```
Clone the repo Clone the repo
``` sh ``` sh
git clone https://github.com/alexander-the-alright/ekho git clone https://github.com/alexander-the-alright/ekho
cd 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 1. On the client machine, change the IP/URL and port in the client source file. This can be
If the server is being run on a separate machine, only run make with client flag done quickly with ```sed -i -e "s/127.0.0.1:1300/YOUR.IP.GOES.HERE:PORT/" client.go```
``` sh 2. On the server machine, change the port in the server source file. This can be done with a
make client similar command: ```sed -i -e "s/1300/PORT/" server.go```. (note: this
``` should match the port from bullet 1)
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. 3. On the server machine, change the user referenced in the systemd service file. This can be
``` sh done with another sed command, ```sed -e -i "s/USER/YOUR_USERNAME/" ekho.service```
make all
```
#### NOTE After making these changes on the respective machines, run either
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. ```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: #### After Installation
``` sh After installation of the server binary, systemd will display the
echo "~/abs/path/to/server.o &" >> ~/.zshrc status of the new service. It should be ```enabled``` and
``` ```running```.
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.
Finally done! Finally done!
### Usage ### Usage
The client uses the following flags The client uses the following flags
``` sh ``` sh
-h - display help message -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
-l - list all quotes -ip <ip:port> - specify alternate server destination
-r [i] - remove; may be run with or without argument -l - list all quotes
-ip - specify alternate server destination -r [i] - remove; may be run with or without argument
-s - specify the size of the receipt buffer -s <i> - specify the size of the receipt buffer
``` ```
The server uses the following flags The server uses the following flags
``` sh ``` sh
-h - display help message -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 ### To Be Implemented
- Log all uses/transaction data each day - 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 - User-specific quotes/quotefiles
- Installation (client-side, at least) via MOTD - Colored printing and coloring quotes
- Edit quotes
[golang]: <https://go.dev/doc/install> [golang]: <https://go.dev/doc/install>
[seqdiag]: <sequencediagram.org> [just]: <https://github.com/casey/just>
+370 -173
View File
@@ -1,7 +1,7 @@
// ============================================================================= // =============================================================================
// Auth: alex // Auth: alex
// File: client.go // File: client.go
// Revn: 01-09-2025 4.0 // Revn: 09-06-2026 3.0.0
// Func: ask server for a message of the day quote // Func: ask server for a message of the day quote
// //
// TODO: remove ioutil import // TODO: remove ioutil import
@@ -24,29 +24,39 @@
// imported check() from soary // imported check() from soary
// 09-29-2023: commented handle() // 09-29-2023: commented handle()
//*10-02-2023: commented main(), and friends //*10-02-2023: commented main(), and friends
//*10-05-2023: /remove/ works //#10-05-2023: /remove/ works
// removed -d flag // removed -d flag
// commented // commented
// 06-12-2024: began added PWFT to /la/ // 06-12-2024: began added PWFT to /la/
// 06-13-2024: finished adding PWFT to /la/ // 06-13-2024: finished adding PWFT to /la/
// commented PWFT stuff // commented PWFT stuff
// STARTED BYTE-BASED PWFT REWRITE // STARTED BYTE-BASED PWFT REWRITE
//*06-14-2024: finished byte-based PWFT rewrite //#06-14-2024: finished byte-based PWFT rewrite
// commented // commented
//*01-09-2025: basically just copy/pasted from /la/ into /r1/, /r2/ //*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
// //
// ============================================================================= // =============================================================================
package main package main
import ( import (
"bufio" // NewReader, ReadString
"io" // io.EOF "io" // io.EOF
"io/ioutil" // ReadFile "io/ioutil" // ReadFile
"flag" // BoolVar, StringVar, Parse "flag" // BoolVar, StringVar, Parse
"fmt" // Println "fmt" // Println
"math/rand" // NewSource, New, Intn, *rand.Rand "math/rand" // NewSource, New, Intn, *rand.Rand
"net" // ResolveTCPAddr, DialTCP, conn.Write,Read "net" // ResolveTCPAddr, DialTCP, conn.Write,Read
"os" // Exit, Create "os" // Exit, Create, Stdin
"strconv" // Atoi, Itoa "strconv" // Atoi, Itoa
"strings" // Split "strings" // Split
"time" // Now, UnixNano "time" // Now, UnixNano
@@ -85,20 +95,37 @@ func check( err error ) {
// get user input // get user input
func in( prompt string ) string { func in( prompt string ) string {
// instantiate reader
reader := bufio.NewReader( os.Stdin )
fmt.Print( prompt ) // print user prompt fmt.Print( prompt ) // print user prompt
var input string // declare var to hold user input // get user input, read until newline
fmt.Scanln( &input ) // get user input 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 // try to convert to an int, discard results
_, err := strconv.Atoi( input ) _, err := strconv.Atoi( input )
// if there was an error, user didn't input an int // if there was an error, user didn't input an int
if err != nil { if err != nil {
// warn user against this // warn user against this
fmt.Println( "Input must be a number" ) 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 // this, like handle() calling handle(), seems like a super
// bad idea, stack-wise... // bad idea, stack-wise...
} }
// once user has properly inputted a number, return string of num // once user has properly inputted a number, return string of num
return input return input
} }
@@ -113,7 +140,7 @@ func seed() *rand.Rand {
// get a random number // get a random number
func draw() string { func draw( qsize int ) string {
rn := seed() // get a random seed rn := seed() // get a random seed
r := rn.Intn( qsize ) // get a random number using seed r := rn.Intn( qsize ) // get a random number using seed
// convert random number to ascii, because converting // convert random number to ascii, because converting
@@ -123,6 +150,273 @@ func draw() string {
} }
// 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] )
if err != nil { // if int conversion failed ( for some reason )
os.Exit( 1 ) // just quit
// TODO make exit codes unique, document them
}
// draw a random number, add to quote request
return "qr@" + draw( size )
}
// receive quote, print
func quoteAnswer( subcom []string ) string {
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 ) + 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
resp = "te@X" // successful response message
} 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 = "lr@" + 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 )
}
resp = "te@success" // set transaction end message
}
return resp
}
// 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 ) + 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 = "e2@" + 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 = "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 a removal and an add
var resp string
resp = "cr@r2@" + subcom[0] + "@ar@"
// server response is text to be edited
fmt.Println( "as is: " + subcom[1] )
fmt.Print( "preview: " ) // won't be useful until pretty print
_ = quoteAnswer( subcom[1:] ) // display quote properly
// get user input for new quote and send
resp = resp + in( "\nupdate -> " )
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( 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@" + inputNumber( "\n-> " )
}
return resp
}
// second remove, determine if success or failure
func secondRemove( subcom []string ) string {
var resp string
// if server says remove succeeded
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
} else if subcom[0] == "error" { // if server says remove failed
fmt.Println( "Remove failed" ) // print failure
resp = "te@error" // set transaction end message
} 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 will not display the
// list, as it should on success
// print unknown status
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 // get server response and print
func handle( conn net.Conn ) { func handle( conn net.Conn ) {
@@ -135,176 +429,37 @@ func handle( conn net.Conn ) {
check( err ) // check for errors check( err ) // check for errors
// split recv'd message over @, separate header from message // split recv'd message over @, separate header from message
msg := strings.Split( string( buffer[:n] ), "@" ) message := strings.Split( string( buffer[:n] ), "@" )
command := message[0]
var resp string // declare response variable var resp string // declare response variable
switch msg[0] { // switch/case over the header switch command { // switch/case over the header
// if message is... // if message is...
case "sa": // /sa/, size answer case "sa": // /sa/, size answer
// convert back half to int, catch error resp = sizeAnswer( message[1:] )
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 )
}
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 case "qa": // /qa/, quote answer
fmt.Println( msg[1] ) // whole-ass just print quote resp = quoteAnswer( message[1:] )
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
// 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]
// 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
resp = "te@X" // successful response message
} 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( msg[2] )
check( err ) // check file write for errors
// cast bytes already written field to int
b, err := strconv.Atoi( msg[1] )
check( err ) // check cast for errors
// 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" )
for p, v := range quotes { // iterate over quotes
// print num of quote, followed by that quote
fmt.Println( p + 1, "\t", v )
}
resp = "te@success" // set transaction end message
}
case "aa": // /aa/, add answer case "aa": // /aa/, add answer
// if server says add succeeded resp = addAnswer( message[1:] )
if msg[1] == "success" { case "la": // /la/, list answer
fmt.Println( "Add successful" ) // print success resp = listAnswer( message[1:] )
resp = "te@success" // set transaction end message case "e1": // /e1/, edit quote ( first transaction )
// if server says add failed resp = firstEdit( message[1:] )
} else if msg[1] == "error" { case "e2": // /e2/, edit quote ( second transaction )
fmt.Println( "Add failed" ) // print fail resp = secondEdit( message[1:] )
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
}
case "r1": // /r1/, remove ( first transaction ) case "r1": // /r1/, remove ( first transaction )
// the idea is that if the user doesn't specify which quote to resp = firstRemove( message[1:] )
// 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
// 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]
// 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@" + in( "\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( msg[2] )
check( err ) // check file write for errors
// cast bytes already written field to int
b, err := strconv.Atoi( msg[1] )
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" )
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-> " )
}
case "r2": // /r2/, remove ( second transaction ) case "r2": // /r2/, remove ( second transaction )
// if server says remove succeeded resp = secondRemove( message[1:] )
if msg[1] == "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" {
fmt.Println( "Remove failed" ) // print failure
resp = "te@error" // set transaction end message
// if unknown status message
} else {
// 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
// list, as it should on success
// print unknown status
fmt.Println( "Unknown error code: " + msg[1] )
// TODO should this be unknown instead of error?
resp = "te@error" // set transaction end message
}
case "br": // /br/, bad request case "br": // /br/, bad request
// client has asked for something nonsensical // client has asked for something nonsensical
// TODO write out to file // TODO write out to file
fmt.Println( "Client sent a bad request" ) fmt.Println( "Client sent a bad request" )
resp = "te@error" // set transaction end message 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 default: // something undefined entirely
// TODO write out to file // TODO write out to file
//fmt.Println( "Message header not recognized" ) //fmt.Println( "Message header not recognized" )
@@ -322,7 +477,7 @@ func handle( conn net.Conn ) {
// globals // 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 var conn net.Conn // keep track of connection
@@ -330,18 +485,40 @@ var conn net.Conn // keep track of connection
var add bool // add new quotes to quote file ( on server ) var add bool // add new quotes to quote file ( on server )
var remove bool // remove quotes from quote file ( on server ) var remove bool // remove quotes from quote file ( on server )
var list bool // request entire quote file from server var list bool // request entire quote file from server
var edit bool // edit a pre-existing quote from quote file ( on server )
var dest string // provide a new destination ip and port var dest string // provide a new destination ip and port
var tsize int // size of transmission buffer var tsize int // size of transmission buffer
var VERS string // version
func main() { func main() {
var v bool // version flag
var vv bool // big version flag
// define flags // define flags
flag.BoolVar( &add, "a", false, "add quote to list" ) flag.BoolVar( &add, "a", false, "add quote to list" )
flag.BoolVar( &remove, "r", false, "remove quote from list" ) flag.BoolVar( &remove, "r", false, "remove quote from list" )
flag.BoolVar( &list, "l", false, "print quote 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.IntVar( &tsize, "s", 256, "transmission size ( bytes )" ) flag.StringVar( &dest, "ip", "127.0.0.1:1300", "ip:port of server" )
flag.Parse() // process flags 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()
// FIXME get better versioning method
VERS = "3.0.0"
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
}
service := dest // declare server ip:port service := dest // declare server ip:port
@@ -375,6 +552,27 @@ func main() {
fmt.Println( "/a/ flag must be used with an arugment" ) fmt.Println( "/a/ flag must be used with an arugment" )
os.Exit( 1 ) 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 case remove: // if remove flag is active
// if arguments were specified // if arguments were specified
if len( flag.Args() ) > 0 { if len( flag.Args() ) > 0 {
@@ -386,7 +584,6 @@ func main() {
// if there was an error, just pretend there's no args // if there was an error, just pretend there's no args
if rerr != nil { if rerr != nil {
command = "r1@init" // remove request 1 command = "r1@init" // remove request 1
// TODO come up w/ useful argument, replace dumvar
} else { } else {
// if user knows the number, take care of it // if user knows the number, take care of it
// arg[0] is a string, so concat is cool // 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
+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)"
+8
View File
@@ -1 +1,9 @@
@user:
shmuley
floglin
@all:
blingo
no but like actually blingo shmingo
i would prefer not to
@default:
thank you for using ekho thank you for using ekho
+150 -24
View File
@@ -1,14 +1,16 @@
// ============================================================================= // =============================================================================
// Auth: alex // Auth: alex
// File: server.go // File: server.go
// Revn: 01-09-2025 5.0 // Revn: 09-06-2026 3.0.0
// Func: host MOTD connection // Func: host MOTD connection
// //
// TODO: remove ioutil import // TODO: add user-specific prints
// add more /codes/ to handle
// add flags, like specify port
// write usage and errors to logfile // write usage and errors to logfile
// remove ioutil import
// send logfile to client on request // send logfile to client on request
// add color printing to qfile
// add flags?
// add more /codes/ to handle
// ============================================================================= // =============================================================================
// CHANGE LOG // CHANGE LOG
// ----------------------------------------------------------------------------- // -----------------------------------------------------------------------------
@@ -31,7 +33,7 @@
// fixed bug in /r2/ where removing quote at final // fixed bug in /r2/ where removing quote at final
// position would break // position would break
// removed deadcode from /r2/, unused "quit" bool? // 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 // different files
// removed implicit newline at end of qfile to stop ghost // removed implicit newline at end of qfile to stop ghost
// line bug in /la/ // line bug in /la/
@@ -43,7 +45,13 @@
// commented // commented
//*06-14-2024: byte count-based PWFT rewrite //*06-14-2024: byte count-based PWFT rewrite
//*06-17-2024: catch keyboard interrupts with os/signal and syscall //*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
// //
// ============================================================================= // =============================================================================
@@ -114,10 +122,10 @@ func fread() string {
// bugs where a blank item was introduced into qlist and calling // bugs where a blank item was introduced into qlist and calling
// /la/ would produce a blank line on the client side that didn't // /la/ would produce a blank line on the client side that didn't
// really exist // really exist
//qfile = qfile[:len( qfile ) - 1] qfile = qfile[:len( qfile )]
// cast bytes to string, split string over newline into array // cast bytes to string, split string over newline into array
qlist = strings.Split( string( qfile ), "\n" ) qlist = strings.Split( string( qfile ), "\n" )
// deal with the trailing
return string( qfile ) // return file as string return string( qfile ) // return file as string
} }
@@ -133,8 +141,8 @@ func writeFile( f string ) {
} }
// handle connections ( new and improved ) // receive from connection, send to get processed, send out response
func handle( conn net.Conn ) { func receive( conn net.Conn ) {
// create buffer to hold read message // create buffer to hold read message
buffer := make( []byte, tsize ) buffer := make( []byte, tsize )
@@ -143,9 +151,38 @@ func handle( conn net.Conn ) {
n, err := conn.Read( buffer[:] ) n, err := conn.Read( buffer[:] )
checkN( err, conn ) // make sure read worked checkN( err, conn ) // make sure read worked
// message anatomy
// command@number[@user]
// @ @ delimiter
// command command, like list request or quote request
// number sequence or quote number
// user quote username if applicable, default if not give
// add request message anatomy
// command@quote[@user]
// quote quote to be added
// user quote username, default if not given
// cast message to string, take first n bytes, split over @ // cast message to string, take first n bytes, split over @
command := strings.Split( string( buffer[:n] ), "@" ) command := strings.Split( string( buffer[:n] ), "@" )
if command[0] == "te" {
conn.Close()
return
}
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 // declare response string
var resp string var resp string
switch command[0] { // switch/case over opcode switch command[0] { // switch/case over opcode
@@ -158,7 +195,7 @@ func handle( conn net.Conn ) {
case "qr": // /qr/, quote request case "qr": // /qr/, quote request
// convert message argument to string to make sure it's a // convert message argument to string to make sure it's a
// valid number // valid number
num, nerr := strconv.Atoi( command[1] ) num, nerr := strconv.Atoi( command[0] )
// nerr will not be nil if comm[1] is not a number // nerr will not be nil if comm[1] is not a number
if nerr != nil { if nerr != nil {
// formulate an error message // formulate an error message
@@ -176,7 +213,7 @@ func handle( conn net.Conn ) {
// why bad? num is - // why bad? num is -
default: default:
// good num, get quote, send off // good num, get quote, send off
resp = "qa@" + qlist[num] // quote answer resp = "qa@" + qlist[num - 1] // quote answer
} }
} }
case "lr": // /lr/, list request case "lr": // /lr/, list request
@@ -223,6 +260,78 @@ func handle( conn net.Conn ) {
qfile = qfile + "\n" + command[1] qfile = qfile + "\n" + command[1]
writeFile( qfile ) writeFile( qfile )
resp = "aa@success" // add answer 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 case "r1": // /r1/, remove request 1
resp = "r1@" // begin crafting response resp = "r1@" // begin crafting response
// file too big for single transmission // file too big for single transmission
@@ -315,27 +424,24 @@ func handle( conn net.Conn ) {
case "te": // /te/, transaction end case "te": // /te/, transaction end
// TODO should I be sending something? // TODO should I be sending something?
// TODO is it better to close now or outside of handle() // TODO is it better to close now or outside of handle()
conn.Close() // close connection and leave //conn.Close() // close connection and leave
return // return from handle(), finish connection return "" // return from handle(), finish connection
default: // opcode not recognized default: // opcode not recognized
// TODO there should be more being down, here, right? // 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 return resp
_, err = conn.Write( []byte( resp ) )
checkN( err, conn ) // make sure write worked
handle( conn ) // call handle() again to get response from client
} }
// globals // globals
var qlist []string // list of quotes var qlist []string // list of quotes
//var qlist = make( map[string][]string )
var qfile string // file object var qfile string // file object
var tsize int // size of transmission buffer var tsize int // size of transmission buffer
var VERS string // version
// main, create port and wait for connection // main, create port and wait for connection
func main() { func main() {
@@ -345,12 +451,32 @@ func main() {
// set interrupt and terminate signals to notify channel // set interrupt and terminate signals to notify channel
signal.Notify( sigs, syscall.SIGINT, syscall.SIGTERM ) 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 for default transmission size
flag.IntVar( &tsize, "s", 256, "transmission size ( bytes )" ) 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() flag.Parse()
qfile = fread() // read quote file, init ( global ) list of quotes // FIXME get better versioning method
VERS = "3.0.0"
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 service := ":1300" // create service on ip and port
// resolve ip address and port // resolve ip address and port
@@ -372,7 +498,7 @@ func main() {
// wait, create connection when found // wait, create connection when found
conn, err := listener.Accept() conn, err := listener.Accept()
check( err ) // make sure connection works check( err ) // make sure connection works
go handle( conn ) // handle connection go receive( conn ) // handle connection
} }
} }