a. Create 2 files, namely server.c and client.c.

When server.c is first run, it will prompt the user to type in how many clients to serve (range 1-5).

When client.c is first run, it prompts the user to type in a username. This username is then sent to the server, to check whether it already exists or not. If it already exists, it will ask for another prompt to type in the username until it is received by the server.

b. When all the clients needed by the server have been collected, each client will start to be given a prompt to type in the required service, namely Container Name, Image Used, Container Startup Command, and Volume. The order in which clients send service requests to the server is determined by the time they register. Example: If username ragnar registers first, followed by username towel, then ragnar will send the request first, followed by towel, and so on.

c. After all service requests from the client are collected, the server then combines them into a docker compose file. Then run the docker compose file that was created earlier

d. Not until there, after the previous docker compose is finished running, client.c will ask for another prompt from the user. The prompt given is in accordance with point (b). If each client does the same thing at point (b), then the server will generate a new docker compose file. Then the container that has been run before will be destroyed, which will then be replaced by the latest service that has been requested from the client earlier.

so, i have made a code untill b. but i think i didn’t finish the a because my server file isn’t checking a name that already exist. and for the b, it having an error, after i finish filling the first client service the second client is not outputing the service request, just a username. and in the server prompt the output format still not correct. lastly for the b and c i still not work for it either,so can anyone help me please. i’m so appreciating your answers.

SERVER.C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>

#define MAX_CLIENTS 5
#define MAX_REQUEST_LEN 256

// Struktur pesan untuk komunikasi dengan clients
struct message {
    long mtype;
    char mtext[MAX_REQUEST_LEN];
};

// Struktur untuk menyimpan informasi layanan dari setiap client
struct service_request {
    char username[MAX_REQUEST_LEN];
    char container_n// Struktur untuk menyimpan informasi layanan dari setiap client
struct service_request {
    char uame[MAX_REQUEST_LEN];
    char image_used[MAX_REQUEST_LEN];
    char start_command[MAX_REQUEST_LEN];
    char volume[MAX_REQUEST_LEN];
};

// Fungsi untuk mengirim pesan ke client
void send_message(int msqid, struct message *msg) {
    if (msgsnd(msqid, msg, MAX_REQUEST_LEN, 0) == -1) {
        perror("msgsnd");
        exit(1);
    }
}

// Fungsi untuk menerima pesan dari client
void receive_message(int msqid, struct message *msg) {
    if (msgrcv(msqid, msg, MAX_REQUEST_LEN, 1, 0) == -1) {
        perror("msgrcv");
        exit(1);
    }
}

// Fungsi untuk set status server
void set_server_status(int status) {
    FILE *fp = fopen("server_status.txt", "w");
    if (fp == NULL) {
        perror("Failed to open server status file");
        exit(1);
    }
    fprintf(fp, "%d", status);
    fclose(fp);
}

// Fungsi untuk mendapatkan status server
int get_server_status() {
    FILE *fp = fopen("server_status.txt", "r");
    if (fp == NULL) {
        perror("Failed to open server sperror("Failed ttatus file");
        exit(1);
    }
    int status;
    fscanf(fp, "%d", &status);
    fclose(fp);
    return status;
}

int main() {
    key_t key;
    int msqid;
    struct message msg;
    struct service_request requests[MAX_CLIENTS]; // Array untuk menyimpan informasi permintaan layanan dari setiap client
    int num_clients = 0;

    // Set status server menjadi berjalan
    set_server_status(1);

    // Buat key untuk message queue
    if ((key = ftok("server.c", 'B')) == -1) {
        perror("ftok");
        exit(1);
    }

    // Buat message queue
    if ((msqid = msgget(key, 0644 | IPC_CREAT)) == -1) {
        perror("msgget");
        exit(1);
    }

    printf("Server is running...n");

    // Menerima jumlah klien yang akan dilayani
    printf("Enter the number of clients to serve (1-5): ");
    scanf("%d", &num_clients);

    // Batasi jumlah klien
    if (num_clients < 1 || num_clients > MAX_CLIENTS) {
        printf("Invalid number of clients. Exiting...n");
        exit(1);
    }

    // Menerima nama pengguna dari setiap klien
    int client_count = 0;
    while (client_count < num_clients) {
        receive_message(msqid, &msg);
        int i;
        for (i = 0; i < client_count; i++) {
            if (strcmp(requests[i].username, msg.mtext) == 0) {
                strcpy(msg.mtext, "exists");
                send_message(msqid, &msg);
                break;
            }
        }
        if (i == client_count) {
            strcpy(requests[client_count].username, msg.mtext);
            client_count++;
            strcpy(msg.mtext, "accepted");
            send_message(msqid, &msg);
        }
    }

    printf("All client usernames accepted.n");

    // Menerima permintaan layanan dari klien yang telah mendaftar
    for (int i = 0; i < num_clients; i++) {
        receive_message(msqid, &msg);
        printf("Received service request from client %s:n", requests[i].username);
        printf("Container Name: %sn", msg.mtext);
        strcpy(requests[i].container_name, msg.mtext);

        receive_message(msqid, &msg);
        printf("Image Used: %sn", msg.mtext);
        strcpy(requests[i].image_used, msg.mtext);

        receive_message(msqid, &msg);
        printf("Start Command: %sn", msg.mtext);
        strcpy(requests[i].start_command, msg.mtext);

        receive_message(msqid, &msg);
        printf("Volume: %sn", msg.mtext);
        strcpy(requests[i].volume, msg.mtext);
    }

    // Set status server menjadi tidak berjalan
    set_server_status(0);

    // Tampilkan layanan yang diminta berdasarkan username
    printf("Service requests:n");
    for (int i = 0; i < num_clients; i++) {
        printf("Username: %sn", requests[i].username);
        printf("Container Name: %sn", requests[i].container_name);
        printf("Image Used: %sn", requests[i].image_used);
        printf("Start Command: %sn", requests[i].start_command);
        printf("Volume: %sn", requests[i].volume);
        printf("----------------------------------------n");
    }

    return 0;
}

CLIENT.C
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <string.h>

#define MAX_REQUEST_LEN 256

// Struktur pesan untuk komunikasi dengan server
struct message {
    long mtype;
    char mtext[MAX_REQUEST_LEN];
};

// Struktur untuk menyimpan informasi permintaan layanan
struct service_request {
    char container_name[MAX_REQUEST_LEN];
    char image_used[MAX_REQUEST_LEN];
    char start_command[MAX_REQUEST_LEN];
    char volume[MAX_REQUEST_LEN];
};

// Fungsi untuk mengirim pesan ke server
void send_message(int msqid, char *message) {
    struct message msg;
    msg.mtype = 1;
    strcpy(msg.mtext, message);
    if (msgsnd(msqid, &msg, MAX_REQUEST_LEN, 0) == -1) {
        perror("msgsnd");
        exit(1);
    }
}

// Fungsi untuk menerima pesan dari server
void receive_message(int msqid, struct message *msg) {
    if (msgrcv(msqid, msg, MAX_REQUEST_LEN, 1, 0) == -1) {
        perror("msgrcv");
        exit(1);
    }
}

// Fungsi untuk mencetak pesan koneksi terputus
void print_disconnected() {
    printf("Connection terminated.n");
}

// Fungsi untuk memeriksa apakah server berjalan
int is_server_running() {
    key_t key;
    int msqid;

    if ((key = ftok("server.c", 'B')) == -1) {
        return 0; // Gagal mendapatkan key, server mungkin tidak berjalan
    }

    // Coba mengakses message queue
    if ((msqid = msgget(key, 0644)) == -1) {
        return 0; // Gagal mengakses message queue, server mungkin tidak berjalan
    }

    return 1; // Server berjalan
}

int main() {
    key_t key;
    int msqid;
    struct message msg;
    struct service_request request; // Deklarasi struct service_request

    // Buat key untuk message queue
    if ((key = ftok("server.c", 'B')) == -1) {
        perror("ftok");
        exit(1);
    }

    // Dapatkan message queue ID
    if ((msqid = msgget(key, 0644 | IPC_NOWAIT)) == -1) {
        // Jika tidak dapat terhubung ke server
        print_disconnected();
        exit(1);
    }

    // Dapatkan status server
    int server_running = is_server_running();

    // Jika server tidak berjalan, keluarkan pesan dan hentikan program
    if (!server_running) {
        print_disconnected();
        exit(1);
    }

    // Input dan kirim username ke server
    do {
        printf("Enter your username: ");
        scanf("%s", msg.mtext);

        send_message(msqid, msg.mtext);
        receive_message(msqid, &msg);

        if (strcmp(msg.mtext, "exists") == 0) {
            printf("Username already exists. Please enter a different username.n");
        }
    } while (strcmp(msg.mtext, "exists") == 0);

    printf("Username accepted.n");

    // Meminta input permintaan layanan
    printf("Enter container name: ");
    scanf("%s", request.container_name);

    printf("Enter image used: ");
    scanf("%s", request.image_used);

    printf("Enter start command: ");
    scanf("%s", request.start_command);

    printf("Enter volume: ");
    scanf("%s", request.volume);

    // Kirim permintaan layanan ke server
    send_message(msqid, request.container_name);
    send_message(msqid, request.image_used);
    send_message(msqid, request.start_command);
    send_message(msqid, request.volume);

    printf("Service request sent.n");

    return 0;
}