**While the API is production-ready, it is still under development and it has regular updates, do not forget to update it regularly by calling `pip install pytelegrambotapi --upgrade`*
It is presumed that you [have obtained an API token with @BotFather](https://core.telegram.org/bots#botfather). We will call this token `TOKEN`.
Furthermore, you have basic knowledge of the Python programming language and more importantly [the Telegram Bot API](https://core.telegram.org/bots/api).
The TeleBot class (defined in \__init__.py) encapsulates all API calls in a single class. It provides functions such as `send_xyz` (`send_message`, `send_document` etc.) and several ways to listen for incoming messages.
Create a file called `echo_bot.py`.
Then, open the file and create an instance of the TeleBot class.
After that declaration, we need to register some so-called message handlers. Message handlers define filters which a message must pass. If a message passes the filter, the decorated function is called and the incoming message is passed as an argument.
Let's define a message handler which handles incoming `/start` and `/help` commands.
```python
@bot.message_handler(commands=['start', 'help'])
def send_welcome(message):
bot.reply_to(message, "Howdy, how are you doing?")
This one echoes all incoming text messages back to the sender. It uses a lambda function to test a message. If the lambda returns True, the message is handled by the decorated function. Since we want all messages to be handled by this function, we simply always return True.
We now have a basic bot which replies a static message to "/start" and "/help" commands and which echoes the rest of the sent messages. To start the bot, add the following to our source file:
The last three lines are necessary to keep the process alive. If they were to be omitted, the program would terminate as soon as bot.polling() is called. They have no impact on the bot's functioning.
To start the bot, simply open up a terminal and enter `python echo_bot.py` to run the bot! Test it by sending commands ('/start' and '/help') and arbitrary text messages.
All types are defined in types.py. They are all completely in line with the [Telegram API's definition of the types](https://core.telegram.org/bots/api#available-types), except for the Message's `from` field, which is renamed to `from_user` (because `from` is a Python reserved token). Thus, attributes such as `message_id` can be accessed directly with `message.message_id`. Note that `message.chat` can be either an instance of `User` or `GroupChat` (see [How can I distinguish a User and a GroupChat in message.chat?](#how-can-i-distinguish-a-user-and-a-groupchat-in-messagechat)).
The Message object also has a `content_type`attribute, which defines the type of the Message. `content_type` can be one of the following strings:
All [API methods](https://core.telegram.org/bots/api#available-methods) are located in the TeleBot class. They are renamed to follow common Python naming conventions. E.g. `getMe` is renamed to `get_me` and `sendMessage` to `send_message`.
### General use of the API
Outlined below are some general use cases of the API.
#### Message handlers
A message handler is a function which is decorated with the `message_handler` decorator of a TeleBot instance. The following examples illustrate the possibilities of message handlers:
All `send_xyz` functions of TeleBot take an optional `reply_markup` argument. This argument must be an instance of `ReplyKeyboardMarkup`, `ReplyKeyboardHide` or `ForceReply`, which are defined in types.py.
There exists an implementation of TeleBot which executes all `send_xyz` and the `get_me` functions asynchronously. This can speed up you bot __significantly__, but it has unwanted side effects if used without caution.
To enable this behaviour, create an instance of AsyncTeleBot instead of TeleBot.
Now, every function that calls the Telegram API is executed in a separate Thread. The functions are modified to return an AsyncTask instance (defined in \__init__.py). Using AsyncTeleBot allows you to do the following:
Sometimes you must send messages that exceed 5000 characters. The Telegram API can not handle that many characters in one request, so we need to split the message in multiples. Here is how to do that using the API:
- num_threads: integer (default 4). Controls the amount of WorkerThreads created for the internal thread pool that TeleBot uses to execute message handlers. Is not used when create_threads is False.
TeleBot's `polling()` function takes an optional none_stop argument. When none_stop equals True, the bot will not exit when it receives an invalid response from the Telegram API servers. none_stop defaults to False.
*Note: You should take caution when using this, because some errors (e.g. if the Telegram servers fail to return data) can not be ignored and the bot would malfunction.*
If you prefer using web hooks to the getUpdates method, you can use the `process_new_messages(messages)` function in TeleBot to make it process the messages that you supply. It takes a list of Message objects.