The identifier of the chat.
The content of the message to be sent. Must be one of the following types: inputMessageText, inputMessageAnimation, inputMessageAudio, inputMessageDocument, inputMessagePhoto, inputMessageRichMessage, inputMessageSticker, inputMessageVideo, inputMessageVideoNote, inputMessageVoiceNote, inputMessageLocation, inputMessageVenue, inputMessageContact.
Adds a message to the list of welcome messages of a chat; requires can_send_welcome_messages administrator right in the chat. There can be up to getOption("welcome_message_count_max") welcome messages in a chat. Request type for Tdjson#addChatWelcomeMessage.