E12. Credentials, Reconnect and SoftAP Provisioning

#include <WiFi.h>                         // the Wi-Fi commands

String ssid = "YOUR_WIFI_SSID";           // your Wi-Fi network name
String password = "YOUR_WIFI_PASSWORD";   // your Wi-Fi password

void setup() {                            // runs once
  Serial.begin(115200);                   // start Serial at the ESP32 speed

  WiFi.begin(ssid, password);             // start joining the network
  Serial.print("Trying Wi-Fi");           // tell the user we are trying
  int tries = 0;                          // how many times we have checked
  while (WiFi.status() != WL_CONNECTED && tries < 20) { // not joined AND under 20 tries
    delay(500);                           // wait half a second
    Serial.print(".");                    // print a dot each time
    tries = tries + 1;                    // count this try
  }
  Serial.println();                       // end the line of dots

  if (WiFi.status() == WL_CONNECTED) {    // did we join?
    Serial.print("Joined. IP address: "); // yes - say so
    Serial.println(WiFi.localIP());       // and show the address
  } else {                                // no - we gave up
    WiFi.softAP("ESP32-Setup");           // make our own network (no password)
    Serial.print("Could not join. Connect to ESP32-Setup, address: "); // tell the user
    Serial.println(WiFi.softAPIP());      // usually 192.168.4.1
  }
}

void loop() {                             // nothing to repeat in this sketch
}

#include <WiFi.h>                         // the Wi-Fi commands
#include <WebServer.h>                    // the web server commands

WebServer server(80);                     // a web server on port 80

void sendForm() {                         // runs when a browser asks for /
  String page = "<h1>Wi-Fi setup</h1>";   // a heading
  page += "<form method='POST' action='/save'>"; // a form that sends to /save
  page += "<p>Network name <input name='ssid'></p>"; // a box called ssid
  page += "<p>Password <input name='password'></p>"; // a box called password
  page += "<button>Send</button>";        // the send button
  page += "</form>";                      // end of the form
  server.send(200, "text/html", page);    // send the page to the browser
}

void handleSave() {                       // runs when the form is sent to /save
  Serial.print("Network name: ");         // a label
  Serial.println(server.arg("ssid"));     // what was typed in the ssid box
  Serial.print("Password: ");             // a label
  Serial.println(server.arg("password")); // what was typed in the password box
  server.send(200, "text/html", "<h1>Received - thank you</h1>"); // reply to the phone
}

void setup() {                            // runs once
  Serial.begin(115200);                   // start Serial at the ESP32 speed
  WiFi.softAP("ESP32-Setup");             // make our own network
  Serial.print("Join ESP32-Setup and open http://"); // tell the user what to do
  Serial.println(WiFi.softAPIP());        // usually 192.168.4.1

  server.on("/", sendForm);               // path / shows the form
  server.on("/save", handleSave);         // path /save reads the form
  server.begin();                         // start the web server
}

void loop() {                             // runs over and over
  server.handleClient();                  // answer any browser that is asking
}