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Http Post and Get fail with multiple values


(m) #1

Im trying to post data from a dht22 to my emoncms server. I was able to post a single value with http post but when I try two values it fails. And when I try http get it fails. Here are the codes and results in the Serial Monitor:

  1. Http Post successful with 1 parameter, Temp:
    void start_test () {
    //For DHT22 Grove Pro
    float h = dht.readHumidity();
    float t = dht.readTemperature();
    dtostrf(t, 4, 2, dataString); //convert flat to char
    Serial.println(dataString);
    }

    void httppost () {
    esp.println(“AT+CIPSTART=“TCP”,”" + server + “”,80");//start a TCP connection.
    if( esp.find(“OK”)) {
    Serial.println(“TCP connection ready”);
    }

    // //CODE USED TO BUILD COMPLETE STRING
    String nodeData=“node=fortnite&data={“a”:”;
    String nodeWithJson=nodeData + dataString + “}”; //COMBINE STRING OBJECT WITH CHAR[]
    String apiKeyString="&apikey=";
    apiKeyString.concat(EMON_APIKEY); //JOIN PARAMETER LITERAL STRING => String Object
    String finalData=nodeWithJson+apiKeyString; //COMBINE BOTH PREVIOUS STRING OBJECTS
    Serial.println(“finalData”);
    Serial.println(finalData);
    delay(1000);
    String postRequest=“POST " + uri + " HTTP/1.1\r\n”+“Host: " + server + “\r\n” + “Accept: " + “/” + "\r\n”+“Content-Length: " + finalData.length() + “\r\n” + “Content-Type: application/x-www-form-urlencoded\r\n”+”\r\n” + finalData;
    Serial.println(“postRequest”);
    Serial.println(postRequest);
    …more code
    }

This is the Post Request:
&node=fortnite&data={"a":28.00}&apikey=mykey

And I get http 200 OK.

  1. This is the Post code that fails with a second parameter, Humidity:

    void start_test () {
    //For DHT22 Grove Pro
    float h = dht.readHumidity();
    float t = dht.readTemperature();
    dtostrf(t, 4, 2, tempString); //convert flat to char
    dtostrf(h, 4, 2, humString); //convert flat to char
    strcpy(dataString,tempString);
    strcat(dataString,humString);
    Serial.println(dataString);
    }

    void httppost () {
    esp.println(“AT+CIPSTART=“TCP”,”" + server + “”,80");//start a TCP connection.
    if( esp.find(“OK”)) {
    Serial.println(“TCP connection ready”);
    }

    // //CODE USED TO BUILD COMPLETE STRING
    String nodeData1="&node=fortnite&data={“t”:";
    String nodeData2=nodeData1 + tempString;
    String nodeData3=nodeData2 + “,“h”:”;
    String nodeData4=nodeData3 + humString;
    String nodeData5=nodeData4 + “}”;
    String apiKeyString="&apikey=";
    apiKeyString.concat(EMON_APIKEY); //JOIN PARAMETER LITERAL STRING => String Object
    String finalData=nodeData5+apiKeyString; //COMBINE BOTH PREVIOUS STRING OBJECTS
    Serial.println(finalData.length());
    Serial.println(finalData);
    delay(1000);
    String postRequest=“POST " + uri + " HTTP/1.1\r\n”+“Host: " + server + “\r\n” + “Accept: " + “/” + "\r\n”+“Content-Length: " + finalData.length() + “\r\n” + “Content-Type: application/x-www-form-urlencoded\r\n”+”\r\n” + finalData;
    Serial.println(“postRequest”);
    Serial.println(postRequest);
    …more code
    }

This is the Post Request:

&node=fortnite&data={"t":28.40,"h":69.20}&apikey=mykey

2.b I even tried the url directly and it works fine:

http://santiapps.com/emoncms/input/post?node=fortnite&data={"t":26.60,"h":49.70}&apikey=mykey

Here is the image of it in my browser
3. I tried this GET request also but it returns a 400 http error:

#include "SoftwareSerial.h"
#include "DHT.h"
#define DHTPIN A1     // what pin we're connected to
#define DHTTYPE DHT22   // DHT 22  (AM2302)
DHT dht(DHTPIN, DHTTYPE);

String ssid ="myssid";
String password="mypwd";
String server = "santiapps.com"; // www.example.com
String uri = "/emoncms/input/post";
#define EMON_APIKEY F("mykey")

byte dat [5];
String temp ,hum;
String data;
char dataString[20];
char tempString[20];
char humString[20];

SoftwareSerial esp(6, 7);// RX, TX

void setup() {
  esp.begin(9600);
  Serial.begin(9600);
  Serial.println("setup");
  reset();
  connectWifi();
}

void reset() {
  Serial.println("reset");
  esp.println("AT+RST");
  delay(1000);
  if(esp.find("OK") ) Serial.println("Module Reset");
}

void connectWifi() {
  Serial.println("connect to wifi");  
  String cmd = "AT+CWJAP=\"" +ssid+"\",\"" + password + "\"";
  esp.println(cmd);
  delay(400);
  while (esp.available()){
     String inData = esp.readStringUntil('\n');
     Serial.println("Got reponse from ESP8266: " + inData);
  }

  if(esp.find("OK")) {
    Serial.println("Connected!");
  } else {
    connectWifi();
    Serial.println("Cannot connect to wifi"); }
}

void start_test () {
  //For DHT22 Grove Pro
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  dtostrf(t, 4, 2, tempString);  //convert flat to char  
  dtostrf(h, 4, 2, humString);  //convert flat to char
  strcpy(dataString,tempString);
  strcat(dataString,humString);
  Serial.println(dataString);
}

void loop(){
  Serial.println("loop");
  start_test();
  httppost();
  delay(100000);//100k ms = 100s or ~ 1.8m
}

void httppost () {
  esp.println("AT+CIPSTART=\"TCP\",\"" + server + "\",80");//start a TCP connection.
  if( esp.find("OK")) {
    Serial.println("TCP connection ready");
  }

//  //CODE USED TO BUILD COMPLETE STRING
  String nodeData1="/emoncms/input/post.json?node=fortnite&json={\"t\":";
  String nodeData2=nodeData1 + tempString;
  String nodeData3=nodeData2 + ",\"h\":";
  String nodeData4=nodeData3 + humString;
  String nodeData5=nodeData4 + "}";
  String apiKeyString="&apikey="; 
  apiKeyString.concat(EMON_APIKEY); //JOIN PARAMETER LITERAL STRING => String Object
  String finalData=nodeData5+apiKeyString; //COMBINE BOTH PREVIOUS STRING OBJECTS
  Serial.println(finalData); 
  delay(1000);
  String getRequest="GET " + finalData + " HTTP/1.0\r\n"+"Host: " + server + "\r\n" + "Connection: keep-alive\r\n\r\n";
  String requestLength = String(getRequest.length());
  Serial.println("getRequest");
  Serial.println(getRequest);

  String sendCmd = "AT+CIPSEND=";//determine the number of caracters to be sent.
  esp.print(sendCmd);
  esp.println(requestLength);
  delay(1000);
  if(esp.find(">")) { 
    Serial.println("Sending.."); 
    esp.print(getRequest);
    if(esp.find("SEND OK")) { 
      Serial.println("Packet sent");
      while (esp.available()) {
        String tmpResp = esp.readString();
        Serial.println(tmpResp);
      }
      // close the connection
      esp.println("AT+CIPCLOSE");
    }
  }
}

And here is the get request:

setup
reset
connect to wifi
Got reponse from ESP8266: AT+CWJAP="myssid","mypwd"

Got reponse from ESP8266: WIFI DISCONNEC
connect to wifi
Got reponse from ESP8266: AT+CWJAP="myssid","mypwd"

Got reponse from ESP8266: busy p...

Connected!
Cannot connect to wifi
loop
29.5051.60
TCP connection ready
/emoncms/input/post.json?node=fortnite&json={"t":29.50,"h":51.60}&apikey=mykey
getRequest
 HTTP/1.0
Host: santiapps.com
Connection: keep-alive

Sending..
Packet sent

+IPD,311:HTTP/1.1 400 Bad Request
Server: nginx
Date: Mon, 08 Oct 2018 02:00:11 GMT
C

Im not sure what is wrong with the post or get request that is making those fail.