This trivial adaptation of the Pachube sample for Netduino doesn't work. It doesn't barf, it just fails silently. I noticed that if you wait a little after the write, the socket reports 315 bytes in its Available
property, but attempting to read the data simply doesn't work - cb
contains zero and the unchanged buffer agrees.
Why can't I read this data? I suspect it's a server response that might well help me figure out what's wrong with the rest of the application.
Here's the code:
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using SecretLabs.NETMF.Hardware.NetduinoPlus;
using SecretLabs.NETMF.Hardware;
public class HelloPachubeSockets
{
static string apiKey = "wggHejZTKTvE6ZplSc5feSs1rQLeD4cYmi7WPYiG0VLIx_TC-isp8CI9vkKq3nQxadhydl3gUiSK8vS5SBd9JCCoXQG-g0N8FXYlYcNjEfJVMQJA-usgijpE1LRT-xw5";
static string feedId = "43974";
static double maxVoltage = 3.3;
static int maxAdcValue = 1023;
static int interval = 20000;
static Socket connection = null;
static Timer timer;
static AnalogInput voltagePort;
static OutputPort lowPort, highPort;
static IPEndPoint remoteEndPoint;
static double V = 0;
static void LogSensor(object state)
{
Debug.Print("time: " + DateTime.Now);
Debug.Print("memory available: " + Debug.GC(true));
try
{
connection = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
connection.SendTimeout = interval / 2;
connection.Connect(remoteEndPoint);
int rawValue = voltagePort.Read();
double value = (rawValue * maxVoltage) / maxAdcValue;
string sample = "voltage," + V.ToString("f");
V += 0.1;
Debug.Print("new message: " + sample);
byte[] contentBuffer = Encoding.UTF8.GetBytes(sample);
const string CRLF = "\r\n";
var requestLine = "PUT /v2/feeds/" + feedId + ".csv HTTP/1.1\r\n";
byte[] requestLineBuffer = Encoding.UTF8.GetBytes(requestLine);
var headers =
"Host: api.pachube.com\r\n" +
"X-PachubeApiKey: " + apiKey + CRLF +
"ContentType: text/csv\r\n" +
"ContentLength: " + contentBuffer.Length + CRLF +
CRLF;
byte[] headersBuffer = Encoding.UTF8.GetBytes(headers);
connection.Send(requestLineBuffer);
connection.Send(headersBuffer);
connection.Send(contentBuffer);
Thread.Sleep(400);
int a = connection.Available;
byte[] r = new byte[a];
int cb = connection.Receive(r, 0, a, SocketFlags.None);
connection.Close();
}
catch
{
Debug.Print("connection failed");
}
}
public static void Main()
{
voltagePort = new AnalogInput(Pins.GPIO_PIN_A1);
lowPort = new OutputPort(Pins.GPIO_PIN_A0, false);
highPort = new OutputPort(Pins.GPIO_PIN_A2, true);
remoteEndPoint = new IPEndPoint(Dns.GetHostEntry("api.pachube.com").AddressList[0], 80);
timer = new Timer(LogSensor, null, 0, interval);
Thread.Sleep(Timeout.Infinite);
}
}
As regards validity of the Pachube key, I checked with cURL and the key and feed details are right.
Looking at http://msdn.microsoft.com/en-us/library/w3xtz6a5.aspx#Y0, you shouldn't need to sleep to wait for a response on the socket as Receive is a blocking operation if the buffer is empty.
What if you tried simplifying your Receive code to something like:
Alternatively, you could explicitly attempt to read something like 256 bytes off of the socket, instead of the available number.