I’m developing a Telegram bot with the python-telegram-bot library. I know that update.message.chat_id provides the chat identifier, but I’m unsure how to obtain user details such as the username, first name, or last name. I reviewed Telegram’s API documentation; however, my attempt with a function like customBot.fetchChat(update.message.chat_id) did not succeed.
Below is an alternative code example:
# Example function to extract user details
def fetch_user_info(msg):
user = msg.from_user
first = user.first_name
last = user.last_name
handle = user.username
return first, last, handle
user_details = fetch_user_info(update.message)
print('User details:', user_details)
hey, try using update.message.from_user to get first_name, last_name, & username. some fields might not be set if the user didnt provide them. works fine in my setup, so no need for fetchChat 
An alternative method is to directly access the properties available in the update.message.from_user object. In my projects, I found that simply reading attributes like first_name, last_name, and username works reliably, as long as the user actually has provided the optional fields like last_name or username. When testing in different environments or chat contexts, it’s important to anticipate cases where certain information might be missing and add proper checks. This approach results in cleaner, more maintainable code without unnecessary API calls.
In my experience with developing bots using python-telegram-bot, direct access to update.message.from_user is the most straightforward approach to retrieve user details. I implemented this method in multiple projects, and it consistently provided reliable results as long as I incorporated proper checks for missing fields. For instance, I created fallback logic to accommodate situations where the last name or username might not be set, which helped prevent potential errors. This direct access method, combined with robust error handling, has proven efficient and effective in managing user data for my bots.
hey, you can just access update.message.from_user directly. sometimes u might not get last_name/username if not set, so check that. works fine in my project, hope it helps!