feature/offerable identity

[JGiter]

| Jira issue | https://energyweb.atlassian.net/browse/MYEN-694 |

ProxyIdentity redesigned as OfferableIdentity, which allows to offer identity with possibility to accept or reject it. For use cases check tests in the proxyidentity package

Design decisions:

• Identity owner doesn't control identity document directly. Identity owns its document
• Identity owner can offer identity by OfferableIdentity.offer
• Owned identity can be operated by OfferableIdentityOperator which extends Operator and therefore can be used in claims workflow. Some Operators methods are excluded:
  • changeOwner - to prevent identity transfer without acknowledgment
  • revokeDelegate - notion of delegate is not defined on offerable identities

[jrhender]

Looks good to me so far 😃

[jrhender]

Looks good, just a few questions

[jrhender]

Does this function need the isOwner modifier?

[JGiter]

If tranasaction sent to ERC1056, then ownership will be checked by ERC1056, but someone who is not the owner might use this method to send tx from asset to some arbitrary contract what potentially could be dangerous. That is why I added this additional safe guarantee.

[jrhender]

Please add isOwner modifier

[jrhender]

If this contract is just doing the events, maybe it's more specific to call it IdentityEvents or maybe IdentityNotifier

[JGiter]

I plan to expand this contract in the future, such as adding methods to return a list of assets or may be batch asset creation

[jrhender]

Why use the 0.5 compiler instead of a higher version (for both this contract and OfferableIdentity)?
I'm not saying it should be higher, I'm not too sure. But it maybe a higher version would mean a contract inheriting this contract could use new features?

[JGiter]

Good idea. Upgraded to 0.8.0

[jrhender]

Please add isOwner modifier

[jrhender]

Looks good

[jrhender]

@JGiter I was taking a look at ERC725X and wondering if maybe OfferableIdentity should be able to create contracts as well. https://github.com/ERC725Alliance/ERC725/blob/master/implementations/contracts/ERC725/ERC725X.sol Maybe it's overkill but just thought I would throw it out there. What do you think?

[JGiter]

@JGiter I was taking a look at ERC725X and wondering if maybe OfferableIdentity should be able to create contracts as well. https://github.com/ERC725Alliance/ERC725/blob/master/implementations/contracts/ERC725/ERC725X.sol Maybe it's overkill but just thought I would throw it out there. What do you think?

May be active assets should be able to do this. If so then it make sense to add such feature in separate ActiveIdentity contract, which extends OfferableIdentity