Abstracting reference to File from sending code

Author: witnessmenow

examples/ESP8266/ImageFromSD/ImageFromSD.ino

@@ -13,11 +13,14 @@
 #include <SPI.h>
 #include <SD.h>
 
+bool isMoreDataAvailable();
+byte getNextByte();
 
 // Initialize Wifi connection to the router
 char ssid[] = "xxxxxxxxxxxxxxxxxxxxxx";              // your network SSID (name)
 char password[] = "yyyyyyyy";                              // your network key
 
+File myFile;
 
 // Initialize Telegram BOT
 #define BOTtoken "XXXXXXXXX:XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"  // your Bot Token (Get from Botfather)
@@ -65,6 +68,14 @@ void setup() {
 
 }
 
+bool isMoreDataAvailable(){
+  return myFile.available();
+}
+
+byte getNextByte(){
+  return myFile.read();
+}
+
 void loop() {
 
   if (millis() > Bot_lasttime + Bot_mtbs)  {
@@ -76,11 +87,11 @@ void loop() {
       JsonObject& payload = jsonBuffer.createObject();
       payload["chat_id"] = bot.messages[0].chat_id;
 
-      File myFile = SD.open("box.jpg");
+      myFile = SD.open("box.jpg");
       if (myFile) {
         Serial.println("box.jpg:");
 
-        bot.sendImageFromFileToTelegram(&myFile, bot.messages[0].chat_id);
+        bot.sendImageFromFileToTelegram(bot.messages[0].chat_id, myFile.size(), isMoreDataAvailable, getNextByte);
         // close the file:
         myFile.close();
         } else {

src/UniversalTelegramBot.cpp

@@ -119,7 +119,7 @@ String UniversalTelegramBot::sendPostToTelegram(String command, JsonObject& payl
   return response;
 }
 
-String UniversalTelegramBot::sendImageFromFileToTelegram(File* file, String chat_id){
+String UniversalTelegramBot::sendImageFromFileToTelegram(String chat_id, int fileSize, MoreDataAvailable moreDataAvailableCallback, GetNextByte getNextByteCallback){
 
   Serial.println("sendImageFromFileToTelegram");
   String response = "";
@@ -153,7 +153,7 @@ String UniversalTelegramBot::sendImageFromFileToTelegram(File* file, String chat
     client->println("User-Agent: arduino/1.0");
     client->println("Accept: */*");
 
-    int contentLength = file->size() + start_request.length() + end_request.length();
+    int contentLength = fileSize + start_request.length() + end_request.length();
     Serial.println("Content-Length: " + String(contentLength));
     client->print("Content-Length: "); client->println(String(contentLength));
     client->println("Content-Type: multipart/form-data; boundary=" + boundry);
@@ -163,11 +163,11 @@ String UniversalTelegramBot::sendImageFromFileToTelegram(File* file, String chat
     Serial.print(start_request);
 
     Serial.println("Sending....");
-    char buffer[512];
+    byte buffer[512];
     int count = 0;
     char ch;
-    while (file->available()) {
-      buffer[count] = file->read();
+    while (moreDataAvailableCallback()) {
+      buffer[count] = getNextByteCallback();
       //client->write(ch);
       //Serial.write(ch);
       count++;

src/UniversalTelegramBot.h

@@ -34,6 +34,9 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 #define SSL_PORT 443
 #define HANDLE_MESSAGES 1
 
+typedef bool (*MoreDataAvailable)();
+typedef byte (*GetNextByte)();
+
 struct telegramMessage{
   String text;
   String chat_id;
@@ -49,7 +52,7 @@ class UniversalTelegramBot
     UniversalTelegramBot (String token, Client &client);
     String sendGetToTelegram(String command);
     String sendPostToTelegram(String command, JsonObject& payload);
-    String sendImageFromFileToTelegram(File* file, String chat_id);
+    String sendImageFromFileToTelegram(String chat_id, int fileSize, MoreDataAvailable moreDataAvailableCallback, GetNextByte getNextByteCallback);
     bool getMe();
     bool sendSimpleMessage(String chat_id, String text, String parse_mode);
     bool sendMessage(String chat_id, String text, String parse_mode);