net-cat

subjects/groupie-trackers/groupie-trackers.audit.en.md

@@ -65,7 +65,9 @@
 
 #### Basic
 
+###### +Does the project runs quickly and effectively? (Favoring recursive, no unnecessary data requests, etc)
 ###### +Does the code obey the [good practices](https://public.01-edu.org/subjects/good-practices.en)?
+###### +Is there a test file for this code?
 
 #### Social
 

subjects/net-cat/net-cat.audit.en.md

@@ -0,0 +1,55 @@
+#### Functional
+
+##### Try running `"./net-cat -p 8080"`.
+###### Is the server listening for connections?
+
+##### Try opening 3 terminals, run on the first terminal the command `"./net-cat -p <port>"` and on the second and third terminal run the command `"./net-cat <host ip> <port>"`.
+###### Does both clients connect to the server with success?
+
+##### Try opening 4 terminals, run on the first terminal the command `"./net-cat -u -p <port>"` and on the second, third and fourth terminal run the command `"./net-cat -u <host ip> <port>"`.
+###### Does all clients connect to the server with [UDP](https://www.privateinternetaccess.com/blog/2018/12/tcp-vs-udp-understanding-the-difference/) connection?
+
+##### Try creating a server and 2 Clients.
+###### Do all Clients receive a message informing that the Client joined the chat?
+
+##### Try creating a server and 2 Clients and send a message using the first Client.
+###### Does the second Client receive the message?
+
+##### Try creating a server and 1 Client and send some messages using this Client. Then create a new Client.
+###### Can the new Client see all the messages?
+
+##### Try creating a server and 3 Clients and send a message using the second Client.
+###### Does all the Clients(first, second and third) received the same message?
+
+##### Try creating a server and use 2 or 3 different computers and create for each computer one Client.
+###### Did the server/Clients connected with success?
+
+##### Try creating a server and 4 Clients and disconnect one of the Clients.
+###### Does the rest of the Clients stay connected?
+
+##### Try creating a server and 3 Clients and disconnect one of the Clients.
+###### Does the rest of the Clients receive a message notifying that the Client left?
+
+##### Try creating a server and 3 Clients. Then send messages between the Clients.
+###### Are the messages identified by the name of each Client and the time that the messages was sent?
+
+###### Is the connections between server and Clients well established?
+
+#### General
+
+###### +Can the Clients change their names?
+###### +Is the chat group informed if a Client changes his name?
+###### +Does the server produce logs about Clients activities?
+###### +Is there more NetCat flags implemented?
+
+#### Basic
+
+###### +Does the project runs quickly and effectively? (Favoring recursive, no unnecessary data requests, etc)
+###### +Does the code obey the [good practices](https://public.01-edu.org/subjects/good-practices.en)?
+###### +Is there a test file for this code?
+
+#### Social
+
+###### +Did you learn anything from this project?
+###### +Can it be open-sourced / be used for other sources?
+###### +Would you recommend/nominate this program as an example for the rest of the school?

subjects/net-cat/net-cat.en.md

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+## net-cat
+
+### Objectives
+
+This project consists on recreating the **NetCat in a Server-Client Architecture** that can run in a server mode on a specified port listening for incoming connections, and it can be used in client mode, trying to connect on a specified port and transmitting information to the server.
+
+- NetCat, `nc` the system command, is a computer network utility for reading from and writing to network connections using TCP or UDP. It is used for anything involving TCP, UDP, or UNIX-domain sockets, it is able to open TCP connections, send UDP packages, listen on arbitrary TCP and UDP ports...
+
+- To see more information about NetCat inspect the manual `man nc`.
+
+Here is a simple example of connection and transmission between Server-Client by creating a TCP socket between server and client.
+
+- Open two terminals, one for the server and the other for Client.
+  - Use the following commands for the server side :
+
+    ```console
+    stuednt$ mawk -W interactive '$0="\033[1;32mServer: \033[0m"$0' | nc -l -p <port>
+    Client: Hello it's the CLIENT talking
+    hello there
+
+    ```
+
+  - Use the following commands for the client side :
+
+    ```console
+    stuednt$ mawk -W interactive '$0="\033[1;32mClient: \033[0m"$0' | nc <host ip> <port>
+    Hello it's the CLIENT talking
+    Server: Hello there
+
+    ```
+
+  - To see the host IP use the command `ifconfig` on the host machine.
+
+Your project must work in a similar way that NetCat works, in other words you must create a group chat. The project must present :
+
+- TCP or UDP connection between server and multiple clients (relation of 1 to many), the type of connection must be established by using a flag, just like `nc`, by default it uses TCP connection, if you want to use UDP connection present the flag `-u`.
+- Each Client must have an user name.
+- Clients must be able to send messages to the chat.
+- Messages sent, must be identified by the time that was sent and the user name of who sent the message.
+- If a Client joins the chat, all the messages sent to the chat must be uploaded to the new Client.
+- If a Client connects to the server, the rest of the Clients must be informed by the server that the Client joined the group.
+- If a Client exits the chat, the rest of the Clients must be informed by the server that the Client left.
+- All Clients must receive the messages sent by other Clients.
+- If a Client leaves the chat, the rest of the Clients must not disconnect.
+
+This project will help you learn about :
+
+- Manipulation of structures.
+- [Net-Cat](https://linuxize.com/post/netcat-nc-command-with-examples/)
+- [TCP/UDP](https://www.privateinternetaccess.com/blog/2018/12/tcp-vs-udp-understanding-the-difference/)
+  - TCP/UDP connection
+  - TCP/UDP socket
+- [Channels](https://tour.golang.org/concurrency/2)
+- [Goroutines](https://tour.golang.org/concurrency/1)
+- IP and [ports](https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers)
+
+### Hints
+
+- Try to find out more about the flags `-u`, `-p` and `-l`.
+
+### Instructions
+
+- Your project must be written in **Go**.
+- Your project must use TCP or UDP.
+- The code must respect the [**good practices**](https://public.01-edu.org/subjects/good-practices.en).
+- It is recommended that the code should present a **test file** for the server connection and the client connection.
+- You have to be able to handle the errors from server side and client side.
+
+### Usage
+
+Here is a simple example of a group chat :
+
+- Server side :
+
+```console
+student$ ./net-cat -p 8080
+listening on port 8080....
+
+```
+
+- Two Clients running at the same time
+
+- Client 2 :
+
+```console
+stuednt$ ./net-cat 192.168.1.123 8080
+wellcome, you are connected
+
+enter user name : client2
+your name is client2
+
+client2 joined the chat...
+client1 joined the chat...
+
+hello
+client2 at 18:12- hello
+client1 at 18:13- hello man
+how are you?
+client2 at 18:15- how are you?
+client1 left the chat...
+
+```
+
+- Client 1 :
+
+```console
+stuednt$ ./net-cat 192.168.1.123 8080
+wellcome, you are connected
+
+enter user name : client1
+your name is client1
+
+client2 joined the chat...
+client1 joined the chat...
+
+client2 at 18:12- hello
+hello man
+client1 at 18:13- hello man
+client2 at 18:15- how are you?
+^C
+```