Flex Kit Attributes

Flex Kit attributes are non-primary attestations (e.g. not COUNTRY, AML, DID, etc) by an attestor on a subject. Any entity can be an attestor and can attest to any data points. Likewise, any single entity can query any attestation if they find it useful.

You can see the implementation on Github.

setAttributes(bytes32 _issuerAndAttr, bytes32 _attrValue, address _account, bytes calldata _sigAccount)

Write an attestation about a given account. On initial call, _sigAccount is required and is the signature of the _account over the message: "I authorize [ISSUER_ADDRESS] to attest to my address [ACCOUNT_ADDRESS]"

On subsequent calls, _sigAccount can be omitted.

// Sign message from account authorizing issuer to post info about account
const msg = `I authorize ${issuer.address.toLowerCase()} to attest to my address ${account.address.toLowerCase()}`;
const sigAccount = await account.signMessage(msg);

// [Optional] If unknown, get the attribute key unique to the issuer
const attrKey = await flexKit
    .connect(issuer)
    getAttributeKey(issuer.address, ethers.utils.id("USER_TYPE"));

// Write that the account is of user_type "admin".
flexKit
  .connect(issuer)
  .setAttributes(
    attrKey,
    ethers.utils.id("ADMIN"),
    account.address,
    sigAccount
  )

setQueryFee(bytes32 _rawAttrName, uint256 _amount)

Set the query fee for a given attribute name. The input for attribute name must be the raw name (i.e. it must not be SHA3-256(ISSUER_ADDR | RAW_ATTR_NAME).

setRevokedAttributes(bytes32 _attrName, bool _status)

Set write access for an issuer on a user's specific attribute name. This will default to false initially so once called, the user must continue to manage this boolean for the given issuer/attribute pair.

The input for attribute name must be the hashed value (i.e. SHA3-256(ISSUSER_ADDR | RAW_ATTR_NAME).

withdraw()

Withdraw any funds from query fees.

getAttributeKey(address _issuer, bytes32 _attrName)

The attribute key is the hash of the issuer address and the attribute name. This ensure that multiple issuers can re-use the same attribute name without collision.

const attrKey = await flexKit
    .connect(issuer)
    getAttributeKey(issuer.address, ethers.utils.id("USER_TYPE"));

Querying Attributes

The query functions are similar to the ones found in Query attributes. The functions also accept primary attributes (i.e. COUNTRY, AML, DID, etc) and will fetch the results from the QuadReader.