Wemos to InfluxDB via Wifi

This is a simple example of how to send data from a Wemos board to InfluxDB  throught wifi.

Tested with Wemos D1 R2 and Arduino IDE.

You should change ssid, password to your wifi.
Also InfluxDB database name and data you are using.

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```c
#include <Arduino.h>

#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#include <ESP8266HTTPClient.h>

#define USE_SERIAL // Comment this line for no serial

const char* ssid = "Your_SSID";
const char* password = "Your_Pass";

ESP8266WiFiMulti WiFiMulti;

void setup()
{
    #ifdef USE_SERIAL
    Serial.begin( 115200 );
    #endif

    WiFi.mode( WIFI_STA );
    WiFiMulti.addAP( ssid, password );
}

void loop()
{
    if( WiFiMulti.run() == WL_CONNECTED ) // wait for WiFi connection
    {
        int sensorValue = analogRead( A0 );
       
        // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 3.2V):
        float voltage = sensorValue * (3.2/1023.0);
       
        #ifdef USE_SERIAL
        Serial.println( voltage );
        #endif
       
        HTTPClient http;

        #ifdef USE_SERIAL
        Serial.print( "[HTTP] begin...\n" );
        #endif
       
        // Start writting to influxbd database: mydb
        // Set database, IP and Port you are using
        http.begin( "http://192.168.1.33:8086/write?db=mydb" );
  
        // Send data to influxbd
        // Set data you are using
        int httpCode = http.POST( "Volts,Bat=Lead-Acid,Ser=pruebas value="+String(voltage) );
       
        #ifdef USE_SERIAL
        if(httpCode == 204) // Data Succesfully Written
        {
            Serial.printf( "Data Succesfully Written... code: %d\n", httpCode );

        }
        else // Data Failed
        {
            Serial.printf( "Data Failed... code: %d\n", httpCode );
            Serial.printf( "Error: %s\n", http.errorToString(httpCode).c_str() );
        }
        #endif
       
        http.end();
    }

    delay( 10000 ); // Wait for 10 seconds
}
```

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