Authorization is associated with a client’s encryption key identifier: auth_key_id. No additional parameters need to be passed into methods following authorization.
Authorization requires that a text message containing an authorization code first be sent to the user’s phone.
This may be done using the auth.sendCode method.
The system will automatically choose how to send the authorization code; there are four possible ways the code can arrive:
The auth.sendCode method also has parameters for enabling/disabling use of flash calls, and allows passing an SMS token that will be included in the sent SMS.
For example, the latter is required in newer versions of android, to use the android SMS receiver APIs.
The returned auth.SentCode object will contain multiple parameters:
|flags||#||Flags, see TL conditional fields|
|type||auth.SentCodeType||Phone code type|
|phone_code_hash||string||Phone code hash, to be stored and later re-used with auth.signIn|
|next_type||flags.1?auth.CodeType||Phone code type that will be sent next, if the phone code is not received within
|timeout||flags.2?int||Timeout for reception of the phone code|
If the message takes too long (
timeout seconds) to arrive at the phone, the auth.resendCode method may be invoked to resend a code of type
If the same happens again, you can use auth.resendCode with the
next_type returned by the previous call to auth.resendCode.
To cancel the verification code use auth.cancelCode.
When user enters verification code, the auth.signIn method must be used to validate it and possibly sign user in.
If the code was entered correctly, but the method returns auth.authorizationSignUpRequired, it means that account with this phone number doesn't exist yet: user needs to provide basic information, accept terms of service and then the new user registration method (auth.signUp) must be invoked.
When trying to sign in using auth.signIn, an error 400 SESSION_PASSWORD_NEEDED may be returned, if the user has two-factor authentication enabled.
In this case, instructions for SRP 2FA authentication must be followed.
To set up two-factor authorization on an already authorized account, follow the SRP 2FA authentication docs.
As a result of authorization, the client key, auth_key_id, becomes associated with the user, and each subsequent API call with this key will be executed with that user’s identity. The authorization method itself returns the relevant user. It is best to immediately store the User ID locally in a binding with the key.
Only a small portion of the API methods are available to unauthorized users:
Other methods will result in an error: 401 UNAUTHORIZED.