TDLightTelegramBots/TelegramBots.wiki/FAQ.md

• How to get picture?
• How to display ChatActions like "typing" or "recording a voice message"?
• How to send photos?
• How do I send photos by file_id?
• How to use custom keyboards?
• How can I run my bot?
• How can I compile my project?
• Method sendMessage() (or other) is deprecated, what should I do?
• Is there any example for WebHook?
• How to use spring boot starter?

How to download photo?

To download a picture (or any other file), you will need the file_path of the file. Let start by finding the photo we want to download, the following method will extract the PhotoSize from a photo sent to the bot (in our case, we are taken the bigger size of those provided):

public PhotoSize getPhoto(Update update) {
    // Check that the update contains a message and the message has a photo
    if (update.hasMessage() && update.getMessage().hasPhoto()) {
        // When receiving a photo, you usually get different sizes of it
        List<PhotoSize> photos = update.getMessage().getPhoto();

        // We fetch the bigger photo
        return photos.stream()
                .max(Comparator.comparing(PhotoSize::getFileSize)).orElse(null);
    }

    // Return null if not found
    return null;
}

Once we have the photo we have to options: The file_path is already present or we need to get it, the following method will handle both of them and return the final file_path:

public String getFilePath(PhotoSize photo) {
    Objects.requireNonNull(photo);

    if (photo.hasFilePath()) { // If the file_path is already present, we are done!
        return photo.getFilePath();
    } else { // If not, let find it
        // We create a GetFile method and set the file_id from the photo
        GetFile getFileMethod = new GetFile();
        getFileMethod.setFileId(photo.getFileId());
        try {
            // We execute the method using AbsSender::execute method.
            File file = execute(getFileMethod);
            // We now have the file_path
            return file.getFilePath();
        } catch (TelegramApiException e) {
            e.printStackTrace();
        }
    }
    
    return null; // Just in case
}

Now that we have the file_path we can download it:

public java.io.File downloadPhotoByFilePath(String filePath) {
    try {
        // Download the file calling AbsSender::downloadFile method
        return downloadFile(filePath);
    } catch (TelegramApiException e) {
        e.printStackTrace();
    }

    return null;
}

The returned java.io.File object will be your photo

How to display ChatActions like "typing" or "recording a voice message"?

Quick example here that is showing ChactActions for commands like "/type" or "/record_audio"

if (update.hasMessage() && update.getMessage().hasText()) {

    String text = update.getMessage().getText();

    SendChatAction sendChatAction = new SendChatAction();
    sendChatAction.setChatId(update.getMessage().getChatId());

    if (text.equals("/type")) {
        // -> "typing"
        sendChatAction.setAction(ActionType.TYPING);
        // -> "recording a voice message"
    } else if (text.equals("/record_audio")) {
        sendChatAction.setAction(ActionType.RECORDAUDIO);
    } else {
        // -> more actions in the Enum ActionType
        // For information: https://core.telegram.org/bots/api#sendchataction
        sendChatAction.setAction(ActionType.UPLOADDOCUMENT);
    }

    try {
        Boolean wasSuccessfull = execute(sendChatAction);
    } catch (TelegramApiException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

How to send photos?

There are several method to send a photo to an user using sendPhoto method: With a file_id, with an url or uploading the file. In this example, we assume that we already have the chat_id where we want to send the photo:

    public void sendImageFromUrl(String url, String chatId) {
        // Create send method
        SendPhoto sendPhotoRequest = new SendPhoto();
        // Set destination chat id
        sendPhotoRequest.setChatId(chatId);
        // Set the photo url as a simple photo
        sendPhotoRequest.setPhoto(new InputFile(url));
        try {
            // Execute the method
            execute(sendPhotoRequest);
        } catch (TelegramApiException e) {
            e.printStackTrace();
        }
    }

    public void sendImageFromFileId(String fileId, String chatId) {
        // Create send method
        SendPhoto sendPhotoRequest = new SendPhoto();
        // Set destination chat id
        sendPhotoRequest.setChatId(chatId);
        // Set the photo url as a simple photo
        sendPhotoRequest.setPhoto(new InputFile(fileId));
        try {
            // Execute the method
            execute(sendPhotoRequest);
        } catch (TelegramApiException e) {
            e.printStackTrace();
        }
    }

    public void sendImageUploadingAFile(String filePath, String chatId) {
        // Create send method
        SendPhoto sendPhotoRequest = new SendPhoto();
        // Set destination chat id
        sendPhotoRequest.setChatId(chatId);
        // Set the photo file as a new photo (You can also use InputStream with a constructor overload)
        sendPhotoRequest.setPhoto(new InputFile(new File(filePath)));
        try {
            // Execute the method
            execute(sendPhotoRequest);
        } catch (TelegramApiException e) {
            e.printStackTrace();
        }
    }

How to send photo by its file_id?

In this example we will check if user sends to bot a photo, if it is, get Photo's file_id and send this photo by file_id to user.

// If it is a photo
if (update.hasMessage() && update.getMessage().hasPhoto()) {
    // Array with photos
    List<PhotoSize> photos = update.getMessage().getPhoto();
    // Get largest photo's file_id
    String f_id = photos.stream()
            .max(Comparator.comparing(PhotoSize::getFileSize))
            .orElseThrow().getFileId();
    // Send photo by file_id we got before
    SendPhoto msg = new SendPhoto()
            .setChatId(update.getMessage().getChatId())
            .setPhoto(new InputFile(f_id))
            .setCaption("Photo");
    try {
        execute(msg); // Call method to send the photo
    } catch (TelegramApiException e) {
        e.printStackTrace();
    }
}

How to use custom keyboards?

Custom keyboards can be appended to messages using the setReplyMarkup. In this example, we will build a simple ReplyKeyboardMarkup with two rows and three buttons per row, but you can also use other types like ReplyKeyboardHide, ForceReply or InlineKeyboardMarkup:

    public void sendCustomKeyboard(String chatId) {
        SendMessage message = new SendMessage();
        message.setChatId(chatId);
        message.setText("Custom message text");

        // Create ReplyKeyboardMarkup object
        ReplyKeyboardMarkup keyboardMarkup = new ReplyKeyboardMarkup();
        // Create the keyboard (list of keyboard rows)
        List<KeyboardRow> keyboard = new ArrayList<>();
        // Create a keyboard row
        KeyboardRow row = new KeyboardRow();
        // Set each button, you can also use KeyboardButton objects if you need something else than text
        row.add("Row 1 Button 1");
        row.add("Row 1 Button 2");
        row.add("Row 1 Button 3");
        // Add the first row to the keyboard
        keyboard.add(row);
        // Create another keyboard row
        row = new KeyboardRow();
        // Set each button for the second line
        row.add("Row 2 Button 1");
        row.add("Row 2 Button 2");
        row.add("Row 2 Button 3");
        // Add the second row to the keyboard
        keyboard.add(row);
        // Set the keyboard to the markup
        keyboardMarkup.setKeyboard(keyboard);
        // Add it to the message
        message.setReplyMarkup(keyboardMarkup);

        try {
            // Send the message
            execute(message);
        } catch (TelegramApiException e) {
            e.printStackTrace();
        }
    }

How can I run my bot?

You don't need to spend a lot of money into hosting your own telegram bot. Basically, there are two options around how to host:

1. Hosting on your own hardware. It can be a Mini-PC like a Raspberry Pi. The costs for the hardware (~35€) and annual costs for power (~7-8€) are low. Keep in mind that your internet connection might be limited and a Mini-Pc is not ideal for a large users base.
2. Run your bot in a Virtual Server/dedicated root server. There are many hosters out there that are providing cheap servers that fit your needs. The cheapest one should be openVZ-Containers or a KVM vServer. Example providers are Hetzner, DigitalOcean, (are providing systems that have a high availability but cost's a bit more) and OVH For a deeper explanation for deploying your bot on DigitalOcean please see the Lesson 5. Deploy your bot chapter in MonsterDeveloper's book

How can I compile my project?

This is just one way, how you can compile it (here with maven). The example below below is compiling the TelegramBotsExample repo.

Method sendMessage() (or other) is deprecated, what should I do?

Please use execute() instead. Example:

SendMessage message = new SendMessage();
//add chat id and text
execute(message);

If you extend TelegramLongPollingCommandBot, then use AbsSender.execute() instead.

Is there any example for WebHook?

Please see the example Bot for https://telegram.me/SnowcrashBot in the TelegramBotsExample repo and also an example bot for Sping Boot from UnAfraid here

How to use spring boot starter

---

Your main spring boot class should look like this:

@SpringBootApplication
public class YourApplicationMainClass {

    public static void main(String[] args) {
        SpringApplication.run(YourApplicationMainClass.class, args);
    }
}

After that your bot will look like:

  //Standard Spring component annotation
  @Component
  public class YourBotClassName extends TelegramLongPollingBot {
    //Bot body.
  }

Also you could just implement LongPollingBot or WebHookBot interfaces. All this bots will be registered in context and connected to Telegram api.