WiFi_Data_Transfer.ino

#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <SD.h>

// WiFi credentials
const char* ssid = "Your_SSID";
const char* password = "Your_PASSWORD";

// S3 credentials and bucket details
const char* bucketName = "your-bucket-name";
const char* region = "your-region"; // e.g., "us-east-1"
const char* accessKey = "your-access-key";
const char* secretKey = "your-secret-key";
const char* fileName = "/data.txt"; // File on SD card to upload

// AWS S3 endpoint
const char* host = "s3.amazonaws.com";
const int httpsPort = 443;

// SD card details
#define SD_CS_PIN 5 // Adjust based on your SD card module wiring

void setup() {
  Serial.begin(115200);

  // Initialize WiFi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("WiFi connected!");

  // Initialize SD card
  if (!SD.begin(SD_CS_PIN)) {
    Serial.println("SD card initialization failed!");
    while (1);
  }
  Serial.println("SD card initialized.");

  // Upload file to S3
  if (uploadFileToS3(fileName)) {
    Serial.println("File uploaded successfully!");
  } else {
    Serial.println("File upload failed.");
  }
}

bool uploadFileToS3(const char* filePath) {
  File file = SD.open(filePath);
  if (!file) {
    Serial.println("Failed to open file for reading.");
    return false;
  }

  // Calculate file size
  size_t fileSize = file.size();

  // Read file contents
  String fileContent = "";
  while (file.available()) {
    fileContent += (char)file.read();
  }
  file.close();

  // Prepare S3 signature (use your preferred method for generating the signature)
  String signature = generateS3Signature(filePath, fileSize);

  // Create HTTPS client
  WiFiClientSecure client;
  client.setInsecure();

  if (!client.connect(host, httpsPort)) {
    Serial.println("Connection to S3 failed!");
    return false;
  }

  // HTTP PUT request to upload the file
  String url = String("/") + bucketName + filePath;
  client.println("PUT " + url + " HTTP/1.1");
  client.println("Host: " + String(host));
  client.println("Content-Type: text/plain");
  client.println("Content-Length: " + String(fileSize));
  client.println("Authorization: " + signature);
  client.println("x-amz-date: 20241122T000000Z");
  client.println();
  client.print(fileContent);

  // Wait for response
  while (client.connected()) {
    String line = client.readStringUntil('\n');
    if (line == "\r") break;
  }

  // Check HTTP response
  String response = client.readString();
  Serial.println("S3 Response:");
  Serial.println(response);

  return response.indexOf("200 OK") != -1;
}

String generateS3Signature(const char* filePath, size_t fileSize) {
  // Add logic to generate S3 signature (HMAC-SHA256)
  // This is a placeholder. Use an external library or service to create the signature.
  return "AWS4-HMAC-SHA256 Placeholder_Signature";
}

void loop() {
  // Do nothing
}