Unable to http post/get to thingspeak

Projects Networking, Protocols, and Devices
1

I have this code that I have used for a while to post data from an Arduino/WiFiBee vr1 shield with some sensors to a server with some simple PHP POST file that saves it to a mysql db.

I changed the part where the POST gets made, over to a GET in order to send the data to thingspeak where i have some other data stores. This is the part where the data send fails. I can post the entire code but I believe this is where the issue is. The block labeled Send Request is what I changed from the previous working code. I commented out the encoded form because that is for POST only.

In the SM I get the following:

Main Al⸮⸮⸮⸮ɩHj

Sampling UV
The UV voltage value:1207.27 mV
UVIndex is:
1853.16

Sampling MQ2
MQ2 Sensor_volt = 0.05
RS_ratio = 101.40
Rs/R0 = 1267.50

printing co2...
255 134 1 150 72 0 0 0 155
32
Temperature: 32 CO2: 406
Free memory: 245
Already joined network
DeviceID: Wifly-WebClient2
Reporting to cloud...

open thingspeak.com 80
Connected to thingspeak.com

Posted successfully

It seems to post successfully but the data doesnt get posted.

void reportToCloud() {
  data = "";
  Serial.println("Reporting to cloud...");
   if (wifly.available() > 0) {
  char ch = wifly.read();
  Serial.write(ch);
  if (ch == '\n') {
      /* add a carriage return */ 
      Serial.write('\r');
  }
   }
   
   if (wifly.open(site, 80)) {
       Serial.print("Connected to ");
       Serial.println(site);
  
        // Set data to send
        static char outstr1[15];
        static char outstr2[15];
        static char outstr3[15];
        static char outstr4[15];
    
        String dataString1 = dtostrf(uvindex, 8, 2, outstr1);
        String dataString2 = dtostrf(mq2ratio, 8, 2, outstr2);
        String dataString3 = dtostrf(CO2PPM, 8, 2, outstr3);
        String dataString4 = dtostrf(temperature, 8, 2, outstr4);
        data = String("uvindex=" + dataString1 + "&mq2=" + dataString2 + "&age=" + dataString3 + "&name=" + dataString4);    
        Serial.print(data); //name = temp && age = co2
        //Reset all values
        uvindex = 0;
        mq2ratio = 0;
        CO2PPM = 0;
        temperature = 0;
        
        /* Send the request */
        String getData = "GET"+ HOST + "/update.json?api_key="+ API + "&"+ field3 +"="+ dataString4 +"&"+ field4 +"="+dataString3 + "HTTP/1.0";
        Serial.println(getData);
        /* Send the request */
        wifly.println(getData);
        wifly.println("Host: thingspeak.com"); // SERVER ADDRESS HERE TOO
        //wifly.println("Content-Type: application/x-www-form-urlencoded" );
        wifly.print("Content-Length: ");
        wifly.println(data.length());
        wifly.println();
        wifly.print(data);
        Serial.println("Posted successfully");
   } else {
       Serial.println(">>Failed to connect");
   }

   if (Serial.available() > 0) {
  wifly.write(Serial.read());
   }
   
   wifly.close();
}
2

Try a space after the first quote. If that doesn’t help, compare your code very carefully with a known good example, say here: Arduino - HTTP Request | Arduino Tutorial

Edit:

Same here. A missing space

3

Ok so i made your suggested corrections and have been testing but even before getting to the actual HTTP post Im working on getting the string right. I started printing the string after building it and noticed it wasnt printing in the SM AT ALL. So I started debugging it and got this far:

String getData = "GET /update?api_key=15KW7SVKY7L97FSF&field3=44";//&field4=99";// HTTP/1.1";

where ive truncated it after the first data point because the moment I include &field4=99, i start getting that empty Serial.println(getData). And if that string is blank then the HTTP request will obviously fail.

4

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