Rob Dobson / RdWebServer

A simple web server mainly based on ideas from Jasper Schuurmans Netduino web server

Dependents:   RdBlindsServer SpideyWallWeb RdGasUseMonitor

A fast and reliable web server for MBED! http://robdobson.com/2015/08/a-reliable-mbed-webserver/

It has a very neat way to implement REST commands and can serve files from local storage (on LPC1768 for instance) and from SD cards. It also has a caching facility which is particularly useful for serving files from local storage.

The server can be run in the main() thread (and has a sub-2ms response time if this is done) or in a mbed-rtos thread which increases the response time to (a still respectable) 30ms or so.

The latest project that uses this is here - https://developer.mbed.org/users/Bobty/code/SpideyWallWeb/

int main (void)
{
    // Ethernet interface
    EthernetInterface::init();

    // Connect ethernet
    EthernetInterface::connect();

    // Init the web server
    pc.printf("Starting web server\r\n");
    char* baseWebFolder = "/sd/";  // should be /sd/ for SDcard files - not used for local file system
    RdWebServer webServer;
    
    // Add commands to handle the home page and favicon
    webServer.addCommand("", RdWebServerCmdDef::CMD_LOCALFILE, NULL, "index.htm", true);
    webServer.addCommand("favicon.ico", RdWebServerCmdDef::CMD_LOCALFILE, NULL, NULL, true);
    
    // Add the lightwall control commands
    webServer.addCommand("name", RdWebServerCmdDef::CMD_CALLBACK, &lightwallGetSystemName);
    webServer.addCommand("clear", RdWebServerCmdDef::CMD_CALLBACK, &lightwallClear);
    webServer.addCommand("rawfill", RdWebServerCmdDef::CMD_CALLBACK, &lightwallRawFill);
    webServer.addCommand("fill", RdWebServerCmdDef::CMD_CALLBACK, &lightwallFill);
    webServer.addCommand("showleds", RdWebServerCmdDef::CMD_CALLBACK, &lightwallShowLeds);
    
    // Start the server
    webServer.init(WEBPORT, &led4, baseWebFolder);
    webServer.run();

}

// Get system name - No arguments required
char* lightwallGetSystemName(int method, char*cmdStr, char* argStr, char* msgBuffer, int msgLen, 
                int contentLen, unsigned char* pPayload, int payloadLen, int splitPayloadPos)
{
    // Perform any required actions here ....

    // ...

    // Return the system name
    return systemName;
}

This server was originally based on a Netduino web server from Jasper Schuurmans but has been optimised for speed.

RdWebServer.cpp

Committer:
Bobty
Date:
2013-09-19
Revision:
1:75bb184de749
Parent:
0:b5b4d07f7827
Child:
2:9d8793c23b46

File content as of revision 1:75bb184de749:

#include "RdWebServer.h"

#define MAX_CMDSTR_LEN 100
#define MAX_ARGSTR_LEN 100

RdWebServer::RdWebServer()
{
    _serverIsListening = false;
    _pStatusLed = NULL;
}

RdWebServer::~RdWebServer()
{
}

bool RdWebServer::init(int port, DigitalOut* pStatusLed)
{
    _port = port;
    _pStatusLed = pStatusLed;
        
//    _socketSrv.set_blocking(true);


    //setup tcp socket
    if(_socketSrv.bind(port)< 0) 
    {
        printf("tcp server bind failed.\n\r");
        return false;
    }
    else 
    {
        printf("tcp server bind successed.\n\r");
        _serverIsListening = true;
    }

    if(_socketSrv.listen(1) < 0)
    {
        printf("tcp server listen failed.\n\r");
        return false;
    }
    else 
    {
        printf("tcp server is listening...\n\r");
    }
    
    return true;
}

bool RdWebServer::extractCmdArgs(char* buf, char* pCmdStr, int maxCmdStrLen, char* pArgStr, int maxArgStrLen)
{
    *pCmdStr = '\0';
    *pArgStr = '\0';
    int cmdStrLen = 0;
    int argStrLen = 0;
    if (buf == NULL)
        return false;
    char* pSlash1 = strchr(buf, '/');
    if (pSlash1 == NULL)
        return false;
    pSlash1++;
    while(*pSlash1)
    {
        if (cmdStrLen >= maxCmdStrLen-1)
            break;
        if ((*pSlash1 == '/') || (*pSlash1 == ' ') || (*pSlash1 == '\n'))
            break;
        *pCmdStr++ = *pSlash1++;
        *pCmdStr = '\0';
        cmdStrLen++;
    }
    if ((*pSlash1 == '\0') || (*pSlash1 == ' ') || (*pSlash1 == '\n'))
        return true;
    *pSlash1++;
    while(*pSlash1)
    {
        if (argStrLen >= maxArgStrLen-1)
            break;
        if ((*pSlash1 == ' ') || (*pSlash1 == '\n'))
            break;
        *pArgStr++ = *pSlash1++;
        *pArgStr = '\0';
        argStrLen++;
    }
    return true;
}
  
void RdWebServer::run()
{
    TCPSocketConnection client;
    bool clientIsConnected = false;

    //listening for http GET request
    while (isListening()) 
    {
        //blocking mode(never timeout)
        if(_socketSrv.accept(client)<0) 
        {
            printf("failed to accept connection.\n\r");
        }
        else
        {
            printf("connection success!\n\rIP: %s\n\r",client.get_address());
            clientIsConnected = true;
            if (_pStatusLed != NULL)
                *_pStatusLed = true;
            
            while(clientIsConnected) 
            {
                char buffer[1024] = {};
                switch(client.receive(buffer, 1023)) 
                {
                    case 0:
                        printf("recieved buffer is empty.\n\r");
                        clientIsConnected = false;
                        break;
                    case -1:
                        printf("failed to read data from client.\n\r");
                        clientIsConnected = false;
                        break;
                    default:
                        printf("Recieved Data: %d\n\r\n\r%.*s\n\r",strlen(buffer),strlen(buffer),buffer);
                        if(buffer[0] == 'G' && buffer[1] == 'E' && buffer[2] == 'T' ) 
                        {
                            printf("GET request incomming.\n\r");
                            char cmdStr[MAX_CMDSTR_LEN];
                            char argStr[MAX_ARGSTR_LEN];
                            if (extractCmdArgs(buffer+3, cmdStr, MAX_CMDSTR_LEN, argStr, MAX_ARGSTR_LEN))
                            {
                                printf("CmdStr %s\n\r", cmdStr);
                                printf("ArgStr %s\n\r", argStr);
                                for (std::vector<RdWebServerCmdDef*>::iterator it = _commands.begin() ; it != _commands.end(); ++it)
                                {
                                    if (strcasecmp((*it)->_pCmdStr, cmdStr) == 0)
                                    {
                                        printf("FoundCmd %s\n\r", cmdStr);
                                        ((*it)->_callback)(argStr);
                                    }
                                }
                            }
                            
                            //setup http response header & data
                            char echoHeader[256] = {};
                            sprintf(echoHeader,"HTTP/1.1 200 OK\n\rContent-Length: %d\n\rContent-Type: text\n\rConnection: Close\n\r\n\r",strlen(buffer));
                            client.send(echoHeader,strlen(echoHeader));
                            client.send(cmdStr,strlen(cmdStr));
                            clientIsConnected = false;
                            printf("done.\n\r");
                        }
                        break;
                }
            }
            printf("close connection.\n\rtcp server is listening...\n\r");
            client.close();
            if (_pStatusLed != NULL)
                *_pStatusLed = false;
        }
    }
}

void RdWebServer::addCommand(char* pCmdStr, CmdCallbackType callback)
{
    _commands.push_back(new RdWebServerCmdDef(pCmdStr, callback));
}