Merge pull request #5 from sandeepmistry/websocket

Add initial WebSocket client

Author: mbanzi

ArduinoHttpClient.h

@@ -6,5 +6,6 @@
 #define ArduinoHttpClient_h
 
 #include "HttpClient.h"
+#include "WebSocketClient.h"
 
 #endif

HttpClient.cpp

@@ -439,15 +439,15 @@ int HttpClient::responseStatusCode()
                 delay(kHttpWaitForDataDelay);
             }
         }
-        if ( (c == '\n') && (iStatusCode < 200) )
+        if ( (c == '\n') && (iStatusCode < 200 && iStatusCode != 101) )
         {
             // We've reached the end of an informational status line
             c = '\0'; // Clear c so we'll go back into the data reading loop
         }
     }
     // If we've read a status code successfully but it's informational (1xx)
     // loop back to the start
-    while ( (iState == eStatusCodeRead) && (iStatusCode < 200) );
+    while ( (iState == eStatusCodeRead) && (iStatusCode < 200 && iStatusCode != 101) );
 
     if ( (c == '\n') && (iState == eStatusCodeRead) )
     {

WebSocketClient.cpp

@@ -0,0 +1,371 @@
+// (c) Copyright Arduino. 2016
+// Released under Apache License, version 2.0
+
+#include "b64.h"
+
+#include "WebSocketClient.h"
+
+WebSocketClient::WebSocketClient(Client& aClient, const char* aServerName, uint16_t aServerPort)
+ : HttpClient(aClient, aServerName, aServerPort),
+   iTxStarted(false),
+   iRxSize(0)
+{
+}
+
+WebSocketClient::WebSocketClient(Client& aClient, const String& aServerName, uint16_t aServerPort) 
+ : HttpClient(aClient, aServerName, aServerPort),
+   iTxStarted(false),
+   iRxSize(0)
+{
+}
+
+WebSocketClient::WebSocketClient(Client& aClient, const IPAddress& aServerAddress, uint16_t aServerPort)
+ : HttpClient(aClient, aServerAddress, aServerPort),
+   iTxStarted(false),
+   iRxSize(0)
+{
+}
+
+int WebSocketClient::begin(const char* aPath)
+{
+    // start the GET request
+    beginRequest();
+    connectionKeepAlive();
+    int status = get(aPath);
+
+    if (status == 0)
+    {
+        uint8_t randomKey[13];
+        char base64RandomKey[21];
+
+        // create a random key for the connection upgrade
+        for (int i = 0; i < (int)sizeof(randomKey); i++)
+        {
+            randomKey[i] = random(0x01, 0xff);
+        }
+        memset(base64RandomKey, 0x00, sizeof(base64RandomKey));
+        b64_encode(randomKey, sizeof(randomKey), (unsigned char*)base64RandomKey, sizeof(base64RandomKey));
+
+        // start the connection upgrade sequence
+        sendHeader("Upgrade", "websocket");
+        sendHeader("Connection", "Upgrade");
+        sendHeader("Sec-WebSocket-Key", base64RandomKey);
+        sendHeader("Sec-WebSocket-Version", "13");
+        endRequest();
+
+        status = responseStatusCode();
+
+        if (status > 0)
+        {
+            skipResponseHeaders();
+        }
+    }
+
+    iRxSize = 0;
+
+    // status code of 101 means success
+    return (status == 101) ? 0 : status;
+}
+
+int WebSocketClient::begin(const String& aPath)
+{
+    return begin(aPath.c_str());
+}
+
+int WebSocketClient::beginMessage(int aType)
+{
+    if (iTxStarted)
+    {
+        // fail TX already started
+        return 1;
+    }
+
+    iTxStarted = true;
+    iTxMessageType = (aType & 0xf);
+    iTxSize = 0;
+
+    return 0;
+}
+
+int WebSocketClient::endMessage()
+{
+    if (!iTxStarted)
+    {
+        // fail TX not started
+        return 1;
+    }
+
+    // send FIN + the message type (opcode)
+    HttpClient::write(0x80 | iTxMessageType);
+
+    // the message is masked (0x80)
+    // send the length
+    if (iTxSize < 126)
+    {
+        HttpClient::write(0x80 | (uint8_t)iTxSize);
+    }
+    else if (iTxSize < 0xffff)
+    {
+        HttpClient::write(0x80 | 126);
+        HttpClient::write((iTxSize >> 8) & 0xff);
+        HttpClient::write((iTxSize >> 0) & 0xff);
+    }
+    else
+    {
+        HttpClient::write(0x80 | 127);
+        HttpClient::write((iTxSize >> 56) & 0xff);
+        HttpClient::write((iTxSize >> 48) & 0xff);
+        HttpClient::write((iTxSize >> 40) & 0xff);
+        HttpClient::write((iTxSize >> 32) & 0xff);
+        HttpClient::write((iTxSize >> 24) & 0xff);
+        HttpClient::write((iTxSize >> 16) & 0xff);
+        HttpClient::write((iTxSize >> 8) & 0xff);
+        HttpClient::write((iTxSize >> 0) & 0xff);
+    }
+
+    uint8_t maskKey[4];
+
+    // create a random mask for the data and send
+    for (int i = 0; i < (int)sizeof(maskKey); i++)
+    {
+        maskKey[i] = random(0xff);
+    }
+    HttpClient::write(maskKey, sizeof(maskKey));
+
+    // mask the data and send
+    for (int i = 0; i < (int)iTxSize; i++) {
+        iTxBuffer[i] ^= maskKey[i % sizeof(maskKey)];
+    }
+
+    size_t txSize = iTxSize;
+
+    iTxStarted = false;
+    iTxSize = 0;
+
+    return (HttpClient::write(iTxBuffer, txSize) == txSize) ? 0 : 1;
+}
+
+size_t WebSocketClient::write(uint8_t aByte)
+{
+    return write(&aByte, sizeof(aByte));
+}
+
+size_t WebSocketClient::write(const uint8_t *aBuffer, size_t aSize)
+{
+    if (iState < eReadingBody)
+    {
+        // have not upgraded the connection yet
+        return HttpClient::write(aBuffer, aSize);
+    }
+
+    if (!iTxStarted)
+    {
+        // fail TX not   started
+        return 0;
+    }
+
+    // check if the write size, fits in the buffer
+    if ((iTxSize + aSize) > sizeof(iTxBuffer))
+    {
+        aSize = sizeof(iTxSize) - iTxSize;
+    }
+
+    // copy data into the buffer
+    memcpy(iTxBuffer + iTxSize, aBuffer, aSize);
+
+    iTxSize += aSize;
+    
+    return aSize;
+}
+
+int WebSocketClient::parseMessage()
+{
+    flushRx();
+
+    // make sure 2 bytes (opcode + length)
+    // are available
+    if (HttpClient::available() < 2)
+    {
+        return 0;
+    }
+
+    // read open code and length
+    uint8_t opcode = HttpClient::read();
+    int length = HttpClient::read();
+
+    if ((opcode & 0x0f) == 0)
+    {
+        // continuation, use previous opcode and update flags
+        iRxOpCode |= opcode;
+    }
+    else
+    {
+        iRxOpCode = opcode;
+    }
+
+    iRxMasked = (length & 0x80);
+    length &= 0x7f;
+
+    // read the RX size
+    if (length < 126)
+    {
+        iRxSize = length;
+    }
+    else if (length == 126)
+    {
+        iRxSize = (HttpClient::read() << 8) | HttpClient::read();
+    }
+    else
+    {
+        iRxSize = ((uint64_t)HttpClient::read() << 56) | 
+                    ((uint64_t)HttpClient::read() << 48) | 
+                    ((uint64_t)HttpClient::read() << 40) | 
+                    ((uint64_t)HttpClient::read() << 32) | 
+                    ((uint64_t)HttpClient::read() << 24) | 
+                    ((uint64_t)HttpClient::read() << 16) | 
+                    ((uint64_t)HttpClient::read() << 8)  |
+                    (uint64_t)HttpClient::read(); 
+    }
+
+    // read in the mask, if present
+    if (iRxMasked)
+    {
+        for (int i = 0; i < (int)sizeof(iRxMaskKey); i++)
+        {
+            iRxMaskKey[i] = HttpClient::read();
+        }
+    }
+
+    iRxMaskIndex = 0;
+
+    if (TYPE_CONNECTION_CLOSE == messageType())
+    {
+        flushRx();
+        stop();
+        iRxSize = 0;
+    }
+    else if (TYPE_PING == messageType())
+    {
+        beginMessage(TYPE_PONG);
+        while(available())
+        {
+            write(read());
+        }
+        endMessage();
+
+        iRxSize = 0;
+    }
+    else if (TYPE_PONG == messageType())
+    {
+        flushRx();
+        iRxSize = 0;
+    }
+
+    return iRxSize;
+}
+
+int WebSocketClient::messageType()
+{
+    return (iRxOpCode & 0x0f);
+}
+
+bool WebSocketClient::isFinal()
+{
+    return ((iRxOpCode & 0x80) != 0);
+}
+
+String WebSocketClient::readString()
+{
+    int avail = available();
+    String s;
+
+    if (avail > 0)
+    {
+        s.reserve(avail);
+
+        for (int i = 0; i < avail; i++)
+        {
+            s += (char)read();
+        }
+    }
+
+    return s;
+}
+
+int WebSocketClient::ping()
+{
+    uint8_t pingData[16];
+
+    // create random data for the ping
+    for (int i = 0; i < (int)sizeof(pingData); i++)
+    {
+        pingData[i] = random(0xff);
+    }
+
+    beginMessage(TYPE_PING);
+    write(pingData, sizeof(pingData));
+    return endMessage();
+}
+
+int WebSocketClient::available()
+{
+    if (iState < eReadingBody)
+    {
+        return HttpClient::available();
+    }
+
+    return iRxSize;
+}
+
+int WebSocketClient::read()
+{
+    byte b;
+
+    if (read(&b, sizeof(b)))
+    {
+        return b;
+    }
+
+    return -1;
+}
+
+int WebSocketClient::read(uint8_t *aBuffer, size_t aSize)
+{
+    int readCount = HttpClient::read(aBuffer, aSize);
+
+    if (readCount > 0)
+    {
+        iRxSize -= readCount;
+
+        // unmask the RX data if needed
+        if (iRxMasked)
+        {
+            for (int i = 0; i < (int)aSize; i++, iRxMaskIndex++) {
+                aBuffer[i] ^= iRxMaskKey[iRxMaskIndex % sizeof(iRxMaskKey)];
+            }
+        }
+    }
+
+    return readCount;
+}
+
+int WebSocketClient::peek()
+{
+    int p = HttpClient::peek();
+
+    if (p != -1 && iRxMasked)
+    {
+        // unmask the RX data if needed
+        p = (uint8_t)p ^ iRxMaskKey[iRxMaskIndex % sizeof(iRxMaskKey)];
+    }
+
+    return p;
+}
+
+void WebSocketClient::flushRx()
+{
+    while(available())
+    {
+        read();
+    }
+}