Striped Data or Retrieved Page -Saved to SD - Simple Example
Posted: Sun Dec 13, 2015 8:10 amThe Following sketch can be used to transfer data from ESP to ESP or retrieve a remote page and strip HTML etc.
This is a simple adaptation of the existing Arduino code for drop in use on ESP.......
This is a simple adaptation of the existing Arduino code for drop in use on ESP.......
Code: Select all
//
// This has been adapted for the ESP8266 to allow the retrieval of any specific data
// from any specific resource, just supply the URI.
// Supply Port IP URL and search String data to strip headers or even ALL HTML
//
// In this example...(I am hosting and collecting from isolated units to provide Data to Web)
// this strips the All the HTML from a Google scripted chart and provides the RAW Chart Data
//
// Provide a routine specifically inside your own sketch and edit the search String.....
// This can also function as SPIFFS/SD to SPIFFS/SD for the ESP-AP connected devices.....
//
// This is the simple way, you will need to fine tune the "Stripping Searches" to your needs.............
//
// Gets a file from the Internet and saves it to the SD card
// Removes the incoming HTTP header, saves the file only
// This example gets the XML cricket score from synd.cricbuzz.com **** From Original Sketch !!!
//
// References - Arduino Example sketches from IDE by David A. Mellis et al.:
// -- File --> Examples --> Ethernet --> WebClient
// http://www.arduino.cc/en/Tutorial/WebClient
// -- File --> Examples --> SD --> ReadWrite
// http://www.arduino.cc/en/Tutorial/ReadWrite
//
// Author: W.A. Smith Date: 10 June 2015 <--- Original Arduino Sketch
// http://startingelectronics.org/software/arduino/save-web-file-to-SD-card/
//
/*
The data here has been stripped by the sketch from the Hosted Google Chart page.......
Headers are Optional, add 1 more loop to the search for "["
'Time / GMT', 'InTmp', 'InHum', 'ExTmp', 'ExHum', 'SySVcc', 'DSTemp0', 'DSTemp1', 'DSTemp2', 'DSTemp3', 'DSTemp4'
'13 Dec - 11:49:25',16.80,38.40,15.50,40.10,3.43,15.56,-0.06,15.63,13.38,16.56
'13 Dec - 11:50:25',16.80,38.30,15.50,40.00,3.43,15.56,0.00,15.63,13.44,16.56
'13 Dec - 11:51:25',16.80,38.50,15.50,40.10,3.43,15.50,0.00,15.63,13.44,16.56
'13 Dec - 11:52:25',16.80,38.40,15.50,40.20,3.43,15.50,0.06,15.69,13.44,16.56
'13 Dec - 11:53:25',16.80,38.50,15.50,40.10,3.42,15.50,0.06,15.63,13.44,16.56
'13 Dec - 11:54:25',16.80,38.50,15.50,40.10,3.43,15.50,0.06,15.69,13.38,16.56
.
.
.
.
*/
#include <SPI.h>
#include <WiFiClient.h>
#include <SD.h>
#include <ESP8266WiFi.h>
IPAddress server(192, 168, 1, 5); // This is serving the data from 5 DS18B20's and 2 DHT22's
WiFiClient client;
const char* ssid = "Your-SSID";
const char* password = "Your-Password";
boolean currentLineIsBlank = true;
File theFile;
void setup() {
Serial.begin(115200);
Serial.println("");
WiFi.begin(ssid, password);
Serial.print("Connecting to ");
Serial.println(ssid);
// Wait for connection
uint8_t i = 0;
while (WiFi.status() != WL_CONNECTED && i++ < 20) {//wait 10 seconds
delay(500);
}
if(i == 21){
Serial.print("Could not connect to");
Serial.println(ssid);
while(1) delay(500);
}
Serial.print("Connected! IP address: ");
Serial.println(WiFi.localIP());
Serial.print(F("Initializing SD card..."));
if (!SD.begin(15)) {
Serial.println(F(" initialization failed!"));
return;
}
if (SD.exists("chartD.txt")){SD.remove("chartD.txt");}// change file name to write to a fresh file here
Serial.println(F(" initialization done."));
Serial.println("connecting...");
// The Start of the Routine to clollect the data...........
// if you get a connection, report back via serial:
if (client.connect(server, 87)) { // Connect to IP and PORT !!!!
Serial.println("connected");
// Make a HTTP request:
client.println("GET /graphic HTTP/1.1"); // change resource to get here, raw - csv - file - PAGE....
client.println();
}
else {
// didn't get a connection to the server:
Serial.println("connection failed");
}
// open the file for writing
Serial.println("Creating file.");
theFile = SD.open("chartD.txt", FILE_WRITE); // change file name to write to here
if (!theFile) {
Serial.println("Could not create file");
while (1);
}
}
void loop() {
// if there are incoming bytes available
// from the server, read them and print them:
if (client.available()) {
char c = client.read();
if (c == '<') { // <HTML> First Tag.....
// Use a marker for self constructed formats, I am using this as it works for stripping header header and my files
c = client.read(); // get file byte to push past tag......not really needed but...Belt & Braces....
for (int i=0;i<3;i++){ // DE-Select the Headers by adding 1......
String dlinew = client.readStringUntil('['); // Strip Google code for chart data extraction
}
// end of HTTP header & Google code, now save requested file
while (client.available()) {
// stay in this loop until the file has been received
String dlinew = client.readStringUntil('[');
String linew = client.readStringUntil(']'); // get data
theFile.println(linew); // save data to file
}
}
}
// if the server's disconnected, stop the client:
if (!client.connected()) {
Serial.println();
Serial.println("disconnecting.");
client.stop();
theFile.close();
Serial.println("Finished writing to file");
// do nothing... Use this as Function in your sketch, Call void getfile() {copy the loop + section from Setup}
delay(-1);
}
}