Postgresql in heroku
in blog on speech-recognition, Annyang, javascript
$ heroku pg:info
$ heroku pg:psql
create table cushion (
uuid varchar(16),
ts timestamp,
ch0 smallint,
ch1 smallint,
ch2 smallint,
ch3 smallint,
ch4 smallint,
ch5 smallint,
ch6 smallint,
ch7 smallint,
ch8 smallint,
ch9 smallint,
ch10 smallint,
ch11 smallint,
ch12 smallint,
ch13 smallint,
ch14 smallint,
ch15 smallint,
ch16 smallint,
ch17 smallint,
ch18 smallint,
ch19 smallint,
ch20 smallint,
ch21 smallint,
ch22 smallint,
ch23 smallint,
ch24 smallint,
ch25 smallint,
ch26 smallint,
ch27 smallint,
ch28 smallint,
ch29 smallint,
ch30 smallint
);
create index iuuid on cushion(uuid);
https://lastminuteengineers.com/esp32-arduino-ide-tutorial/
https://randomnerdtutorials.com/esp32-access-point-ap-web-server/
https://arduinojson.org/v6/example/generator/
#include <WiFi.h>
#define LED 2
String ssid = "ESP32-AP-" + String(random(1111,9999));
String password = "1234567890";
WiFiServer server(80);
String header;
char* S2C(String s){
if(s.length()!=0){
char *p = const_cast<char*>(s.c_str());
return p;
}
}
void _initAP()
{
Serial.println("softAP mode. ");
pinMode(LED,OUTPUT);
WiFi.softAP(S2C(ssid), S2C(password));
IPAddress IP = WiFi.softAPIP();
Serial.print("AP IP address: ");
Serial.println(IP);
server.begin();
}
void setup() {
Serial.begin(115200);
_initAP();
}
void _softAP()
{
WiFiClient client = server.available(); // Listen for incoming clients
if (client) { // If a new client connects,
Serial.println("New Client."); // print a message out in the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected()) { // loop while the client's connected
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
header += c;
if (c == '\n') { // if the byte is a newline character
if (currentLine.length() == 0) {
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println("Connection: close");
client.println();
String payload = "";
payload += "<!DOCTYPE html>";
payload += "<html>";
payload += "<body>";
payload += "Helloworld";
payload += "</body>";
payload += "</html>\n\n";
client.print(S2C(payload));
/*
client.println("<!DOCTYPE html><html>");
client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
client.println("<link rel=\"icon\" href=\"data:,\">");
client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");
client.println(".button { background-color: #4CAF50; border: none; color: white; padding: 16px 40px;");
client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");
client.println(".button2 {background-color: #555555;}</style></head>");
client.println("<body><h1>ESP32 Web Server</h1>");
client.println("</body></html>");
client.println();
*/
} else { // if you got a newline, then clear currentLine
currentLine = "";
}
} else if (c != '\r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
}
}
header = "";
client.stop();
Serial.println("Client disconnected.");
Serial.println("");
}
}
void loop(){
_softAP();
}
https://github.com/prampec/IotWebConf
https://randomnerdtutorials.com/decoding-and-encoding-json-with-arduino-or-esp8266/
https://arduinojson.org/v5/assistant/
