Arduino + Module SIM900 + PHP + Mysql - POST method problem

Question

Good afternoon to all!,

I am developing a project that consists in the communication of a module SIM900 with an application, and doing the interaction of the two will be a server WEB + Database.

The APP, Database and PHP page items are already working perfectly.

PROBLEM: I am having problem in the communication of module SIM900 by the POST method with the page that will make the "ADD" of the information in the Mysql database.

I was able to add the information to the database using the GET method (via URL)

AT+SAPBR=1,1

AT+HTTPINIT

AT+HTTPPARA="URL","site/add.php?variável1=xx&Variavel2=xx&Variavel3=xx"

AT+HTTPACTION=0

However for security reasons I have to use the POST method, and there is the problem... When I try to send the data anyway by Arduino+sim900 (AT+HTTPDATA,AT+CIPSEND or some other), simply "empty" information arrives to me on the site and consequently "empty" values are added in the database as in the image below:

Current code of the ADD.php page in the Database:

include("connect.php");

$link=Connection();

$Bateria=$_POST["Bateria"];
$Odometro=$_POST["Odometro"];
$Consumo=$_POST["Consumo"];
$Carro_Padrao=$_POST["Carro_Padrao"];

$query = "INSERT INTO `u984057597_app`.`SMS_Recebidos`(`timeStamp`,`Bateria`,`Odometro`,`Consumo`,`Carro_Padrao`) VALUES (DATE_SUB(now(), INTERVAL 3 HOUR),'".$Bateria."','".$Odometro."','".$Consumo."','".$Carro_Padrao."')"; 

mysql_query($query,$link);
mysql_close($link);

Has anyone had this same problem and managed to solve it? , is it necessary to have an extra command on the add.php page? (it receives the data from Arduino)

Thank you all from now on!

Answer 1

Problem solved!

The configuration that had entered the question was OK and did not require modifications (ADD.php page).

To solve the capture problem (POST method on the website) I had to make some modifications in the standard library of the module SIM900 of the supplier Tinysine, being them:

1- Modificar a linha 37 do arquivo GSM.cpp para o BaudRate 4800 (antigo era 9600).

2- Modificar a linha 4 do arquivo HWSerial.cpp para o BaudRate 4800(antigo era 9600).

3- Adicionar as seguintes sintaxes na programação do arduino:

ORIGINAL

numdata=inet.httpPOST("site", 80, "/arduino/add.php", "variavel=valor&variavel2=valor2",msg, 50);

MODIFIED

char temp_string[64];
char msg[100];
int numdata;
String valor = "Bateria=13.2V&Odometro=10250Km&Consumo=12.3Km/L&Carro_Padrao=A4";
valor.toCharArray(temp_string, 64);
numdata = inet.httpPOST("site", 80, "/arduino/add.php", temp_string, msg, 50);
delay(5000);

In this last step I had to make a kind of concatenation with conversion of variables and only in this way I could solve my problem in question.

Thanks for all your help!

Answer 2

Of:

$variavel1=$_GET["variavel1"];
$variavel2=$_GET["variavel2"];
$variavel3=$_GET["variavel3"];
$variavel4=$_GET["variavel4"];

To:

$variavel1=$_POST["variavel1"];
$variavel2=$_POST["variavel2"];
$variavel3=$_POST["variavel3"];
$variavel4=$_POST["variavel4"];

Also remember to change the method in the form: method=post.