This PR allows _username authorities_ to issue unique usernames that correspond with an account. It also provides two-way lookup, that is from `AccountId` to a single, "primary" `Username` (alongside `Registration`) and multiple unique `Username`s to an `AccountId`. Key features: - Username Authorities added (and removed) via privileged origin. - Authorities have a `suffix` and an `allocation`. They can grant up to `allocation` usernames. Their `suffix` will be appended to the usernames that they issue. A suffix may be up to 7 characters long. - Users can ask an authority to grant them a username. This will take the form `myusername.suffix`. The entire name (including suffix) must be less than or equal to 32 alphanumeric characters. - Users can approve a username for themselves in one of two ways (that is, authorities cannot grant them arbitrarily): - Pre-sign the entire username (including suffix) with a secret key that corresponds to their `AccountId` (for keyed accounts, obviously); or - Accept the username after it has been granted by an authority (it will be queued until accepted) (for non-keyed accounts like pure proxies or multisigs). - The system does not require any funds or deposits. Users without an identity will be given a default one (presumably all fields set to `None`). If they update this info, they will need to place the normal storage deposit. - If a user does not have any username, their first one will be set as `Primary`, and their `AccountId` will map to that one. If they get subsequent usernames, they can choose which one to be their primary via `set_primary_username`. - There are some state cleanup functions to remove expired usernames that have not been accepted and dangling usernames whose owners have called `clear_identity`. TODO: - [x] Add migration to runtimes - [x] Probably do off-chain migration into People Chain genesis - [x] Address a few TODO questions in code (please review) --------- Co-authored-by: Liam Aharon <liam.aharon@hotmail.com> Co-authored-by: Gonçalo Pestana <g6pestana@gmail.com> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io> Co-authored-by: Dónal Murray <donal.murray@parity.io>
Identity Module
Overview
A federated naming system, allowing for multiple registrars to be added from a specified origin.
Registrars can set a fee to provide identity-verification service. Anyone can put forth a
proposed identity for a fixed deposit and ask for review by any number of registrars (paying
each of their fees). Registrar judgements are given as an enum, allowing for sophisticated,
multi-tier opinions.
Some judgements are identified as sticky, which means they cannot be removed except by complete removal of the identity, or by the registrar. Judgements are allowed to represent a portion of funds that have been reserved for the registrar.
A super-user can remove accounts and in doing so, slash the deposit.
All accounts may also have a limited number of sub-accounts which may be specified by the owner; by definition, these have equivalent ownership and each has an individual name.
The number of registrars should be limited, and the deposit made sufficiently large, to ensure no state-bloat attack is viable.
Interface
Dispatchable Functions
For general users
set_identity- Set the associated identity of an account; a small deposit is reserved if not already taken.clear_identity- Remove an account's associated identity; the deposit is returned.request_judgement- Request a judgement from a registrar, paying a fee.cancel_request- Cancel the previous request for a judgement.
For general users with sub-identities
set_subs- Set the sub-accounts of an identity.add_sub- Add a sub-identity to an identity.remove_sub- Remove a sub-identity of an identity.rename_sub- Rename a sub-identity of an identity.quit_sub- Remove a sub-identity of an identity (called by the sub-identity).
For registrars
set_fee- Set the fee required to be paid for a judgement to be given by the registrar.set_fields- Set the fields that a registrar cares about in their judgements.provide_judgement- Provide a judgement to an identity.
For super-users
add_registrar- Add a new registrar to the system.kill_identity- Forcibly remove the associated identity; the deposit is lost.
License: Apache-2.0