ESP8266 Community Forum

- Thu Oct 08, 2015 10:00 am #30882 Hello everyone,

I have been playing with the ESP8266 and it is really cool. Lately I am trying to interface with Thingspeak.com, which was partly successful. As I am not that familiar with http POST and GET requests I am somewhat flying blindly.

I was able to upload data to thingspeak, basically using the example from arduinoesp.com. Now, I am trying to read values from thingspeak via talkbackin order to control my device.

So what I need is to execute a command like this:

Code: Select allGET https://api.thingspeak.com/talkbacks/11111/commands/18?api_key=XXXXXX

or this:

Code: Select allPOST https://api.thingspeak.com/talkbacks/11111/commands/execute
     api_key=XXXXXXX

and get the returned value. I tried a couple of things, but could not get it to work. The internet mostly talks about uploading data to thingspeak, however was not able to find an example for the opposite direction.

Any ideas would be really helpful!

Thanks,
Tommi

- Tue Dec 08, 2015 5:10 pm #36020 any success with reading from thingspeak?

- Tue Dec 08, 2015 11:06 pm #36037 I have been using the following the following arduino code with thing speak for the basic interpreter project.

Posting to thingspeak.

Code: Select allFetchWebUrl(String("api.thingspeak.com/update?key=" + Param0 + "&field" + Param1 + "=" + Param2));

Reading a filed from thingspeak

Code: Select allMyOut =  FetchWebUrl(String("api.thingspeak.com/channels/" + Param1 + "/field/" + Param2 + "/last.xml?api_key=" + Param0));
    MyOut = MyOut.substring(MyOut.indexOf(String("<field" + Param2 + ">") ) + 8, MyOut.indexOf(String("</field" + Param2 + ">")));

function to fetch a url.

Code: Select all#include <WiFiClient.h>
WiFiClient client;

String FetchWebUrl(String URLtoGet)
{
  String str = "             ";
  String ServerToConnectTo = URLtoGet.substring(0, URLtoGet.indexOf("/"));
  String PageToGet = URLtoGet.substring(URLtoGet.indexOf("/"));
  // ServerToConnectTo ;
  //PageToGet = URLtoGet.substring(URLtoGet.indexOf("/"));

  Serial.println(ServerToConnectTo);
  Serial.println(PageToGet);


  if (client.connect(ServerToConnectTo.c_str() , 80))
  {
    client.print(String("GET " + PageToGet + " HTTP/1.1\r\nHost: " +  ServerToConnectTo + "\r\n\r\n"));
    delay(300);
    while (client.available())
    {
      delay(0);
      if (str.endsWith(String("\r\n\r\n")))  str = "";

      str.concat( (const char)client.read());
      delay(0);
    }



    client.stop();
    return str.substring(0, str.indexOf(String(String(char(10)) + "0" )  ));
  }
  client.stop();
  return "";
}

Serial terminal in the chrome browser see https://serialTerminal.com

http://esp8266basic.com
A BASIC interpreter for your ESP

Working now on Autodrop3d. A 3d printer with automatic part ejection system. https://autodrop3d.com