Single instance HTTP Server using WiFly Interface.

Dependents:   WiFlyHTTPServerSample MultiThreadingHTTPServer

This is my implementation for a HTTP Server using the WiFly Interface. Please note that this is still under development.

It may still contain several bugs. I have tested it using a 1768 on an application board plus RN-XV board.

Currently there is only a FileSystem implemented. Also it is limited to GET request.

I try to extend it further so it will be more useful.

Btw, it does NOT work with RTOS, which seems not to be the Problem of my library.

Do not Forget to Import the WiFly Interface into your Project when using this library.

Change History:

REV5: - added support for basic RPC GET request functionality.

REV4: - added argument parsing from the request uri. - documentation extended and updated.

Revision:
0:7a2421e63e74
Child:
1:6b7472d5e9ee
diff -r 000000000000 -r 7a2421e63e74 HTTPConnection.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/HTTPConnection.cpp	Sun May 26 20:13:28 2013 +0000
@@ -0,0 +1,219 @@
+/* HTTPConnection.cpp */
+
+#include "mbed.h"
+#include "HTTPConnection.h"
+
+#include <vector>
+using std::vector;
+
+using std::string;
+
+#if (1 && !defined(TARGET_LPC11U24))
+#define INFO(x, ...) std::printf("[HttpConnection : INFO]"x"\r\n", ##__VA_ARGS__);
+#define WARN(x, ...) std::printf("[HttpConnection : WARN]"x"\r\n", ##__VA_ARGS__);
+#define ERR(x, ...) std::printf("[HttpConnection : ERR]"x"\r\n", ##__VA_ARGS__);
+#else
+#define INFO(x, ...)
+#define WARN(x, ...)
+#define ERR(x, ...)
+#endif
+
+
+
+
+HTTPConnection::HTTPConnection()
+{
+}
+
+
+HTTPConnection::~HTTPConnection()
+{
+    close();
+}
+
+void HTTPConnection::close()
+{
+    m_Msg.headers.clear();
+}
+
+int HTTPConnection::poll()
+{
+    static char buffer[256] = {};
+    static char echoHeader[256] = {};
+
+    
+    int rcvd= 0;
+    INFO("[HTTPConnection]Waiting for new data in connection");
+    //  Try receiving request line
+    rcvd = receiveLine(buffer, 255, 3000); 
+    if (rcvd == -1) {
+        //  there was an error, probably the connection was closed, so close this connection as well
+        INFO("No more data available. Will close this connection now.");
+        close();
+        return -1;
+    }
+
+    //  The Request has not yet been received so try it
+    rcvd = parse(buffer);
+    if (rcvd == -1) {
+        //  Invalid content received, so close the connection
+        INFO("Invalid message received, so sending negative response and closing connection !");
+        sprintf(echoHeader,"HTTP/1.1 400 NOK\n\rContent-Length: %d\n\rContent-Type: text\n\rConnection: Close\n\r\n\r",strlen(buffer));
+        m_Tcp.set_blocking(true, 1500);
+        m_Tcp.send(echoHeader,strlen(echoHeader));
+        m_Tcp.send(buffer,strlen(buffer));
+        close();
+        rcvd = -1;
+        return -1;
+    }
+    //  The request has been received, try receive the body
+    while(rcvd > 0) {
+        rcvd = receiveLine((char*)buffer, 255, 3000); 
+        //  First check if we received an empty line. This would indicate the end of the message or message body.
+        if (rcvd < 0) {
+            //  there was an empty line, so we can start with performing the request
+            INFO("Request Header was received completely. Performing request.");
+            rcvd = 0;
+            break;
+        }
+        else {
+            //  add message body
+            if (parseHeader(buffer) == 0) {
+            }
+            else {
+                WARN("Invalid message header received !");
+            }
+        }
+    }             
+    if (rcvd == 0) {
+        sprintf(echoHeader,"HTTP/1.1 200 OK\n\rContent-Length: %d\n\rContent-Type: text\n\rConnection: Close\n\r\n\r",strlen(buffer));
+        m_Tcp.set_blocking(true);
+        m_Tcp.send_all(echoHeader,strlen(echoHeader));
+        m_Tcp.send_all(buffer,strlen(buffer));
+        
+        /// INSERT PRCESSING OF REQUESST HERE
+        /// END OF PROCESSING REQUEST
+        
+        //  Do not close the connection, it may be reused
+    }
+    INFO("Leaving poll function!");
+    return rcvd;
+}
+
+int HTTPConnection::receiveLine(char* szLine, int nMaxLen, int nTimeout, char cLineTerm)
+{
+    if ((szLine == NULL) || (nMaxLen == 0))
+        return -1;
+    
+    m_Tcp.set_blocking(false);
+    
+    Timer tm;
+    int i;
+    
+    //  Try to receive up to the max number of characters
+    for (i = 0 ; i < nMaxLen-1 ; i++) {
+        int c;
+        c = m_Tcp.receive_all( szLine + i, 1 );
+        //  Check that - if no character was currently received - the timeout period is reached.
+        if ((c == 0) || (c==-1)) {
+            //  no character was read, so check if operation timed out
+            if (tm.read_ms() > nTimeout) {
+                //  Operation timed out
+                INFO("Timeout occured in function 'receiveLine'.");
+                return -1;
+            }
+        }
+        
+        //  Check if line terminating character was received
+        if (szLine[i] == cLineTerm)
+            break;
+    }
+    //  Terminate with \0
+    szLine[i] = 0;
+
+    //  Trim for '\r' linefeed at the end
+    if( (i >0) && (szLine[i-1] == '\r')) {
+        i--;
+        szLine[i] = 0;
+    }
+    INFO("receiveLine : \"%s\".", szLine);
+    
+    //  return number of characters received in the line or return -2 if an empty line was received
+    if ((i == 0) || ((i==1) &&(szLine[0] == '\r')))
+    {
+        //  empty line received, so return -2
+        return -2;
+    }
+    return i;    
+}
+
+int HTTPConnection::parse(const char* buffer)
+{
+    if ((buffer == NULL) || (strlen(buffer) < 4)) {
+        ERR("Buffer content is invalid or too short.");
+        return -1;
+    }
+    
+    vector<std::string> args;
+    args.clear();
+    
+    //  decompose string into a list of arguments
+    char s = 0; // current starting char
+    static char buff[255] = {};
+    for (int i = 0 ; i < strlen(buffer)+1 ; i++) {
+        if ((buffer[i] == ' ') || (buffer[i] == '\n') || (buffer[i] == 0)) {
+            // new arg found
+            strncpy(buff, &buffer[s], i-s);
+            buff[i-s] = 0;
+            INFO("Found argument \"%s\"", buff);
+            args.push_back(std::string(buff));
+            s = i+1;
+        }
+    }
+        
+    if (args.at(0) == "GET") {
+        m_Msg.request = HTTP_RT_GET;
+        m_Msg.uri = args[1];
+        m_Msg.version = args[2];    
+    }
+    else {
+        if (args.at(0) == "POST") {
+            m_Msg.request = HTTP_RT_GET;
+            m_Msg.uri = args[1];
+            m_Msg.version = args[2];    
+        }
+        else {
+            INFO("unhandled message.");
+        }
+    }
+    args.clear();
+    
+    return 1;
+}
+
+
+int HTTPConnection::parseHeader(const char *buffer)
+{
+    if ((strlen(buffer) <3) || (buffer == NULL))
+        return -1;
+        
+    //  decompose string into a touple of <field name> : <field value>
+    static char fieldname[256] = {};
+    static char fieldvalue[256] = {};
+    for (int i = 0 ; i < strlen(buffer)+1 ; i++) {
+        if (buffer[i] == ':') {
+            //  touple found
+            strncpy(fieldname, buffer, i);
+            fieldname[i] = 0;
+            strcpy(fieldvalue, &buffer[i+1]);
+    
+//            m_Msg.headers[fieldname] = fieldvalue;
+            
+            INFO("Header name=\"%s\" : value=\"%s\".", fieldname, fieldvalue);            
+            return 0;
+        }
+    }
+    
+    ERR("Did not recieve a valid header : \"%s\".", buffer);
+    return -1;
+}