Downloading text file from SD card
Posted: Wed Oct 31, 2018 4:21 amHi, I have a few sensors attached to my nodeMCU and i have successfully stored the values in a few text files in a SDcard connected via a sdcard reader. The files are named "1.txt" and "2.txt" I'm using a router that isnt connected to the internet to help connect the nodemcu to the laptop.
How do I display on a website a directory of all the files available inside the sdcard (like the listfiles example) and download the text files over the internet?
I have tried to display a directory to a website using the code below but it it always tells me that 'client' isnt declared in this scope. I'm not sure how to download the file either. I was thinking of the user using 192.168.x.xxx/dir to see the files he could download and when he sees a file named "1.txt" , typing 192.168.x.xxx/1.txt or 192.168.x.xxx/2.txt will download the respective files to his computer.
How do I display on a website a directory of all the files available inside the sdcard (like the listfiles example) and download the text files over the internet?
I have tried to display a directory to a website using the code below but it it always tells me that 'client' isnt declared in this scope. I'm not sure how to download the file either. I was thinking of the user using 192.168.x.xxx/dir to see the files he could download and when he sees a file named "1.txt" , typing 192.168.x.xxx/1.txt or 192.168.x.xxx/2.txt will download the respective files to his computer.
Code: Select all
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <SPI.h>
#include <SD.h>
File root;
const char* ssid = "-----";
const char* password = "------";
WiFiServer server(80);
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(9600);
//while (!Serial) {
// wait for serial port to connect. Needed for native USB port only
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
// Start the server
server.begin();
Serial.println("Server started");
// Print the IP address
Serial.print("Connection IP: ");
Serial.print("http://");
Serial.print(WiFi.localIP());
Serial.println("/");
// }
Serial.print("Initializing SD card...");
if (!SD.begin(15)) {
Serial.println("initialization failed!");
return;
}
Serial.println("initialization done.");
}
void loop() {
WiFiClient client = server.available();
if (!client) {
return;
}
// Wait until the client sends some data
Serial.println("new client");
while (!client.available()) {
delay(1);
}
// Read the first line of the request
String request = client.readStringUntil('\r');
Serial.println(request);
client.flush();
// Match the request
if (request.indexOf("/dir") != -1)
{
root = SD.open("/");
printDirectory(root, 0);
}
}
void printDirectory(File dir, int numTabs) {
while (true) {
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println(""); // do not forget this one
client.println("<!DOCTYPE HTML>");
client.println("<html>");
File entry = dir.openNextFile();
if (! entry) {
// no more files
break;
}
for (uint8_t i = 0; i < numTabs; i++) {
client.print(':');
}
client.print(entry.name());
if (entry.isDirectory()) {
client.println("/");
printDirectory(entry, numTabs + 1);
} else {
// files have sizes, directories do not
client.print("\t\t");
client.println(entry.size(), DEC);
}
entry.close();
}
client.println("</html>");
}