ESP8266 Cant to connect to client - c

Question

I have a very simple mysql database, which can receive new values via a simple command:
http://7751b6b1.ngrok.io/ethernet/data.php?movement=test
If I enter that in my browser "test" gets write to the databank. Now I want to write to that database via my ESP8266:
#include "ESP8266WiFi.h"
//General Definition
const char server[] = "https://7751b6b1.ngrok.io";
//localhost into server via ngrok
const char* MY_SSID = "Gastzugang";
const char* MY_PWD = "12345678";
String mov; //create Text string
WiFiClient client; //Create Wifi client
//Setup
void setup()
{
Serial.begin(115200);
Serial.println("Connecting to "+*MY_SSID);
WiFi.begin(MY_SSID, MY_PWD);
Serial.println("going into wl connect");
int PIR_output=16; // output of pir sensor
while (WiFi.status() != WL_CONNECTED) //not connected, ...waiting to
connect
{
delay(1000);
Serial.print(".");
}
Serial.println("wl connected");
Serial.println("");
Serial.println("Credentials accepted! Connected to wifi\n ");
Serial.println("");
}
void loop() {
if(digitalRead(16) == HIGH) // reading the data from the pir sensor
{
mov = "1";
Serial.println("1");
}
else {
mov = "0" ;
Serial.println("0");
}
if (client.connect(server, 8095)) { //Connecting at the IP address and port
Serial.println("connected to server");
WiFi.printDiag(Serial);
client.println("Get /ethernet/data.php?");
//Connecting and Sending values to database
client.print("movement=");
client.print(mov);
client.stop();
}
else {
// if you didn't get a connection to the server:
Serial.println("connection failed");
}
delay(50);
}
Sensor reading and Wifi connection works wells but I end up with "connection failed".
Can anyone spot the error?
Edit: Updated Code
#include "ESP8266WiFi.h"
//General Definition
const char server[] = "http://b90e9280.ngrok.io"; //localhost?
const char* MY_SSID = "Gastzugang";
const char* MY_PWD = "12345678";
String mov; //create Text string
WiFiClient client; //Create Wifi client
//Setup
void setup()
{
Serial.begin(115200);
Serial.println("Connecting to "+*MY_SSID);
WiFi.begin(MY_SSID, MY_PWD);
Serial.println("going into wl connect");
int PIR_output=16; // output of pir sensor
while (WiFi.status() != WL_CONNECTED) //not connected, ...waiting to
connect
{
delay(1000);
Serial.print(".");
}
Serial.println("wl connected");
Serial.println("");
Serial.println("Credentials accepted! Connected to wifi\n ");
Serial.println("");
}
void loop() {
//here sensor reading einfügen
if (client.connect(server, 80)) { //Connecting at the IP address and port
Serial.println("connected to server");
WiFi.printDiag(Serial);
client.println("Get /ethernet/data.php?"); //making a http request
Serial.println("Get /ethernet/data.php?");
//Connecting and Sending values to database
if(digitalRead(16) == HIGH) // reading the data from the pir sensor
{
mov = "1";
client.println("movement=1");
Serial.println("movement=1");
}
else {
mov = "0" ;
client.println("movement=0");
Serial.println("movement=0");
}
delay(5000);
client.stop();
}
else {
// if you didn't get a connection to the server:
Serial.println("connection failed");
}
delay(50);
}

Answer 1

Documentation isn't clear on this, but WiFiClient only supports http, not https.
It's great that you're using https! But you'll need to use WiFiClientSecure instead of WifiClient.
You'll most likely want to verify the server's identity once you connect. You'll do that using the verify method on the client object. To do that you'll need to know the fingerprint of the certificate the web server uses.
So your code would look something like this:
#include "ESP8266WiFi.h"
//General Definition
#define SERVER_FINGERPRINT "C0 5D 08 5E E1 3E E0 66 F3 79 27 1A CA 1F FC 09 24 11 61 62"
const char server[] = "https://7751b6b1.ngrok.io";
//localhost into server via ngrok
const char* MY_SSID = "Gastzugang";
const char* MY_PWD = "12345678";
String mov; //create Text string
WiFiClientSecure client; //Create Wifi client
//Setup
void setup()
{
Serial.begin(115200);
Serial.println("Connecting to "+*MY_SSID);
WiFi.begin(MY_SSID, MY_PWD);
Serial.println("going into wl connect");
int PIR_output=16; // output of pir sensor
while (WiFi.status() != WL_CONNECTED) //not connected, ...waiting to
connect
{
delay(1000);
Serial.print(".");
}
Serial.println("wl connected");
Serial.println("");
Serial.println("Credentials accepted! Connected to wifi\n ");
Serial.println("");
}
void loop() {
if(digitalRead(16) == HIGH) // reading the data from the pir sensor
{
mov = "1";
Serial.println("1");
}
else {
mov = "0" ;
Serial.println("0");
}
if (client.connect(server, 8095)) { //Connecting at the IP address and port
Serial.println("connected to server");
if (client.verify(SERVER_FINGERPRINT, host)) {
Serial.println("certificate matches");
} else {
Serial.println("certificate doesn't match");
}
WiFi.printDiag(Serial);
client.println("Get /ethernet/data.php?");
//Connecting and Sending values to database
client.print("movement=");
client.print(mov);
client.stop();
}
else {
// if you didn't get a connection to the server:
Serial.println("connection failed");
}
delay(50);
}
The three important changes are:
- defining client to be WiFiClientSecure rather than WiFiClient
- adding a call to client.verify after the connection succeeds
- providing a constant server finger print to compare with
The fingerprint I provided won't work with your server. You'll need to find its fingerprint yourself. You can do this going to it with a web browser like Chrome and clicking on the "Secure" field in the address bar (in Chrome's case). Click on "Certificate", then expand "Details" in the view of the certificate. Scroll to the end and you'll see two fingerprints, SHA-256 and SHA-1. Copy the SHA-1 fingerprint and provide it as a string like the SERVER_FINGERPRINT I included.
You can skip verifying the certificate if you want but then you won't be certain you're actually connecting to the real server instead of a server impersonating it.
There's more info on WiFiClientSecure at Client Secure, including another example of how to find a server's fingerprint under Windows.
If you run into problems, I'd recommend stripping your program down to just the basics - WiFi connect and then WiFiClientSecure; don't worry about the PIR sensor or anything else. Once you get the stripped down version working with your server, transpose the changes you made back into the real program you're trying to get working.
Update
For your revised code, it's written right now as:
client.println("Get /ethernet/data.php?"); //making a http request
Serial.println("Get /ethernet/data.php?");
//Connecting and Sending values to database
if(digitalRead(16) == HIGH) // reading the data from the pir sensor
{
mov = "1";
client.println("movement=1");
Serial.println("movement=1");
}
else {
mov = "0" ;
client.println("movement=0");
Serial.println("movement=0");
}
delay(5000);
client.stop();
}
Try:
client.print("Get /ethernet/data.php?"); //making a http request
Serial.println("Get /ethernet/data.php?");
//Connecting and Sending values to database
if(digitalRead(16) == HIGH) // reading the data from the pir sensor
{
mov = "1";
client.print("movement=1");
Serial.println("movement=1");
}
else {
mov = "0" ;
client.print("movement=0");
Serial.println("movement=0");
}
client.println(" HTTP/1.1");
client.println("Host: 7751b6b1.ngrok.io");
delay(5000);
client.stop();
}
The way it's written now it cuts off the parameters in the URL with a newline, omits the "HTTP/1.1" tag at the end of the line and doesn't specify the virtual host you're trying to contact (may or may not be an issue depending on your server). It needs to send two lines to the web server, looking like:
GET /ethernet/data.php?movement=1 HTTP/1.1
HOST: 7751b6b1.ngrok.io