University of Plymouth - Stages 1, 2 and 3 / Mbed OS Task671-mbedos-FZ429-TCP-dynamic

Simple TCP/IP Server (dynamic web page)

Dependents:   TASKHTML

main.cpp

Committer:
noutram
Date:
2019-12-04
Revision:
4:094d7d0f9a1f
Parent:
3:265121e8c2cc

File content as of revision 4:094d7d0f9a1f:

#include "mbed.h"
#include "EthernetInterface.h"
#include "TCPServer.h"
#include "TCPSocket.h"
#include <iostream>
#include <string> 

#define HTTP_STATUS_LINE "HTTP/1.0 200 OK"
#define HTTP_HEADER_FIELDS "Content-Type: text/html; charset=utf-8"
#define HTTP_MESSAGE_BODY1 ""                                    \
"<html>" "\r\n"                                                  \
"  <body style=\"display:flex;text-align:center\">" "\r\n"       \
"    <div style=\"margin:auto\">" "\r\n"                         \
"      <h1>Hello World</h1>" "\r\n"                              \
"      <p>The LDR value is "                                     

#define HTTP_MESSAGE_BODY2 ""                                    \
       "</p>" "\r\n"                                             \
"    </div>" "\r\n"                                              \
"  </body>" "\r\n"                                               \
"</html>"

#define HTTP_RESPONSE HTTP_STATUS_LINE "\r\n"   \
                      HTTP_HEADER_FIELDS "\r\n" \
                      "\r\n"                    \
                      HTTP_MESSAGE_BODY "\r\n"

#define IP        "10.0.0.10"
#define NETMASK   "255.0.0.0"
#define GATEWAY   "10.0.0.1"

AnalogIn ldr(PA_0);


int main()
{
    printf("Basic HTTP server example\n");
    
    //Configure an ethernet connection
    EthernetInterface eth;
    eth.set_network(IP, NETMASK, GATEWAY);
    eth.connect();
    printf("The target IP address is '%s'\n", eth.get_ip_address());
    
    //Now setup a web server
    TCPSocket srv;           //TCP/IP Server
    TCPSocket* clt_sock;      //Socket for communication
    SocketAddress clt_addr;  //Address of incoming connection
    
    /* Open the server on ethernet stack */
    srv.open(&eth);
    
    /* Bind the HTTP port (TCP 80) to the server */
    srv.bind(eth.get_ip_address(), 80);
    
    /* Can handle 5 simultaneous connections */
    srv.listen(5);
    
    while (true) {
        using namespace std;
        //Block and wait on an incoming connection
        clt_sock=srv.accept();
        printf("accept %s:%d\n", clt_addr.get_ip_address(), clt_addr.get_port());
        
        //Uses a C++ string to make it easier to concatinate
        string response;
        //This is a C string
        char ldr_str[64];
        
        //Read the LDR value
        float u = ldr;
        
        //Convert to a C String
        sprintf(ldr_str, "%5.3f", u );
        printf("LDR: %5.3f\n\r", u);
        
        //Build the C++ string response
        response = HTTP_MESSAGE_BODY1;
        response += ldr_str;
        response += HTTP_MESSAGE_BODY2;
        
        //Send static HTML response (as a C string)
        clt_sock->send(response.c_str(), response.size()+6);    
        
        clt_sock->close();
        wait_us(100000);
    }
}