.. _entities: ======== Entities ======== The library widely uses the concept of "entities". An entity will refer to any :tl:`User`, :tl:`Chat` or :tl:`Channel` object that the API may return in response to certain methods, such as :tl:`GetUsersRequest`. .. note:: When something "entity-like" is required, it means that you need to provide something that can be turned into an entity. These things include, but are not limited to, usernames, exact titles, IDs, :tl:`Peer` objects, or even entire :tl:`User`, :tl:`Chat` and :tl:`Channel` objects and even phone numbers **from people you have in your contact list**. To "encounter" an ID, you would have to "find it" like you would in the normal app. If the peer is in your dialogs, you would need to `client.get_dialogs() `. If the peer is someone in a group, you would similarly `client.get_participants(group) `. Once you have encountered an ID, the library will (by default) have saved their ``access_hash`` for you, which is needed to invoke most methods. This is why sometimes you might encounter this error when working with the library. You should ``except ValueError`` and run code that you know should work to find the entity. .. contents:: What is an Entity? ================== A lot of methods and requests require *entities* to work. For example, you send a message to an *entity*, get the username of an *entity*, and so on. There are a lot of things that work as entities: usernames, phone numbers, chat links, invite links, IDs, and the types themselves. That is, you can use any of those when you see an "entity" is needed. .. note:: Remember that the phone number must be in your contact list before you can use it. You should use, **from better to worse**: 1. Input entities. For example, `event.input_chat `, `message.input_sender `, or caching an entity you will use a lot with ``entity = await client.get_input_entity(...)``. 2. Entities. For example, if you had to get someone's username, you can just use ``user`` or ``channel``. It will work. Only use this option if you already have the entity! 3. IDs. This will always look the entity up from the cache (the ``*.session`` file caches seen entities). 4. Usernames, phone numbers and links. The cache will be used too (unless you force a `client.get_entity() `), but may make a request if the username, phone or link has not been found yet. In recent versions of the library, the following two are equivalent: .. code-block:: python async def handler(event): await client.send_message(event.sender_id, 'Hi') await client.send_message(event.input_sender, 'Hi') If you need to be 99% sure that the code will work (sometimes it's simply impossible for the library to find the input entity), or if you will reuse the chat a lot, consider using the following instead: .. code-block:: python async def handler(event): # This method may make a network request to find the input sender. # Properties can't make network requests, so we need a method. sender = await event.get_input_sender() await client.send_message(sender, 'Hi') await client.send_message(sender, 'Hi') Getting Entities ================ Through the use of the :ref:`sessions`, the library will automatically remember the ID and hash pair, along with some extra information, so you're able to just do this: .. code-block:: python # (These examples assume you are inside an "async def") # # Dialogs are the "conversations you have open". # This method returns a list of Dialog, which # has the .entity attribute and other information. # # This part is IMPORTANT, because it fills the entity cache. dialogs = await client.get_dialogs() # All of these work and do the same. username = await client.get_entity('username') username = await client.get_entity('t.me/username') username = await client.get_entity('https://telegram.dog/username') # Other kind of entities. channel = await client.get_entity('telegram.me/joinchat/AAAAAEkk2WdoDrB4-Q8-gg') contact = await client.get_entity('+34xxxxxxxxx') friend = await client.get_entity(friend_id) # Getting entities through their ID (User, Chat or Channel) entity = await client.get_entity(some_id) # You can be more explicit about the type for said ID by wrapping # it inside a Peer instance. This is recommended but not necessary. from telethon.tl.types import PeerUser, PeerChat, PeerChannel my_user = await client.get_entity(PeerUser(some_id)) my_chat = await client.get_entity(PeerChat(some_id)) my_channel = await client.get_entity(PeerChannel(some_id)) .. note:: You **don't** need to get the entity before using it! Just let the library do its job. Use a phone from your contacts, username, ID or input entity (preferred but not necessary), whatever you already have. All methods in the :ref:`telethon-client` call `.get_input_entity() ` prior to sending the request to save you from the hassle of doing so manually. That way, convenience calls such as `client.send_message('username', 'hi!') ` become possible. Every entity the library encounters (in any response to any call) will by default be cached in the ``.session`` file (an SQLite database), to avoid performing unnecessary API calls. If the entity cannot be found, additonal calls like :tl:`ResolveUsernameRequest` or :tl:`GetContactsRequest` may be made to obtain the required information. Entities vs. Input Entities =========================== .. note:: This section is informative, but worth reading. The library will transparently handle all of these details for you. On top of the normal types, the API also make use of what they call their ``Input*`` versions of objects. The input version of an entity (e.g. :tl:`InputPeerUser`, :tl:`InputChat`, etc.) only contains the minimum information that's required from Telegram to be able to identify who you're referring to: a :tl:`Peer`'s **ID** and **hash**. They are named like this because they are input parameters in the requests. Entities' ID are the same for all user and bot accounts, however, the access hash is **different for each account**, so trying to reuse the access hash from one account in another will **not** work. Sometimes, Telegram only needs to indicate the type of the entity along with their ID. For this purpose, :tl:`Peer` versions of the entities also exist, which just have the ID. You cannot get the hash out of them since you should not be needing it. The library probably has cached it before. Peers are enough to identify an entity, but they are not enough to make a request with them. You need to know their hash before you can "use them", and to know the hash you need to "encounter" them, let it be in your dialogs, participants, message forwards, etc. .. note:: You *can* use peers with the library. Behind the scenes, they are replaced with the input variant. Peers "aren't enough" on their own but the library will do some more work to use the right type. As we just mentioned, API calls don't need to know the whole information about the entities, only their ID and hash. For this reason, another method, `client.get_input_entity() ` is available. This will always use the cache while possible, making zero API calls most of the time. When a request is made, if you provided the full entity, e.g. an :tl:`User`, the library will convert it to the required :tl:`InputPeer` automatically for you. **You should always favour** `client.get_input_entity() ` **over** `client.get_entity() ` for this reason! Calling the latter will always make an API call to get the most recent information about said entity, but invoking requests don't need this information, just the :tl:`InputPeer`. Only use `client.get_entity() ` if you need to get actual information, like the username, name, title, etc. of the entity. To further simplify the workflow, since the version ``0.16.2`` of the library, the raw requests you make to the API are also able to call `client.get_input_entity() ` wherever needed, so you can even do things like: .. code-block:: python await client(SendMessageRequest('username', 'hello')) The library will call the ``.resolve()`` method of the request, which will resolve ``'username'`` with the appropriated :tl:`InputPeer`. Don't worry if you don't get this yet, but remember some of the details here are important. Full Entities ============= In addition to :tl:`PeerUser`, :tl:`InputPeerUser`, :tl:`User` (and its variants for chats and channels), there is also the concept of :tl:`UserFull`. This full variant has additional information such as whether the user is blocked, its notification settings, the bio or about of the user, etc. There is also :tl:`messages.ChatFull` which is the equivalent of full entities for chats and channels, with also the about section of the channel. Note that the ``users`` field only contains bots for the channel (so that clients can suggest commands to use). You can get both of these by invoking :tl:`GetFullUser`, :tl:`GetFullChat` and :tl:`GetFullChannel` respectively. Accessing Entities ================== Although it's explicitly noted in the documentation that messages *subclass* `ChatGetter ` and `SenderGetter `, some people still don't get inheritance. When the documentation says "Bases: `telethon.tl.custom.chatgetter.ChatGetter`" it means that the class you're looking at, *also* can act as the class it bases. In this case, `ChatGetter ` knows how to get the *chat* where a thing belongs to. So, a `Message ` is a `ChatGetter `. That means you can do this: .. code-block:: python message.is_private message.chat_id await message.get_chat() # ...etc `SenderGetter ` is similar: .. code-block:: python message.user_id await message.get_input_user() message.user # ...etc Quite a few things implement them, so it makes sense to reuse the code. For example, all events (except raw updates) implement `ChatGetter ` since all events occur in some chat. Summary ======= TL;DR; If you're here because of *"Could not find the input entity for"*, you must ask yourself "how did I find this entity through official applications"? Now do the same with the library. Use what applies: .. code-block:: python # (These examples assume you are inside an "async def") async with client: # Does it have an username? Use it! entity = await client.get_entity(username) # Do you have a conversation open with them? Get dialogs. await client.get_dialogs() # Are they participant of some group? Get them. await client.get_participants('TelethonChat') # Is the entity the original sender of a forwarded message? Get it. await client.get_messages('TelethonChat', 100) # NOW you can use the ID, anywhere! await client.send_message(123456, 'Hi!') entity = await client.get_entity(123456) print(entity) Once the library has "seen" the entity, you can use their **integer** ID. You can't use entities from IDs the library hasn't seen. You must make the library see them *at least once* and disconnect properly. You know where the entities are and you must tell the library. It won't guess for you.