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.

Diff: RdWebServer.cpp

Revision:
1:75bb184de749
Parent:
0:b5b4d07f7827
Child:
2:9d8793c23b46
--- a/RdWebServer.cpp	Wed Sep 18 21:36:50 2013 +0000
+++ b/RdWebServer.cpp	Thu Sep 19 12:06:18 2013 +0000
@@ -1,5 +1,8 @@
 #include "RdWebServer.h"
 
+#define MAX_CMDSTR_LEN 100
+#define MAX_ARGSTR_LEN 100
+
 RdWebServer::RdWebServer()
 {
     _serverIsListening = false;
@@ -43,6 +46,43 @@
     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()
 {
@@ -82,15 +122,29 @@
                         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(buffer,strlen(buffer));
+                            client.send(cmdStr,strlen(cmdStr));
                             clientIsConnected = false;
-                            printf("echo back done.\n\r");
+                            printf("done.\n\r");
                         }
                         break;
                 }
@@ -103,3 +157,8 @@
     }
 }
 
+void RdWebServer::addCommand(char* pCmdStr, CmdCallbackType callback)
+{
+    _commands.push_back(new RdWebServerCmdDef(pCmdStr, callback));
+}
+