Quadrata Integration
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Query a single attribute

Use the getAttributes() function from the QuadReader smart contract to query a single attribute about a passport holder.

Requirements

Installation

Install @quadrata/contracts package
npm i @quadrata/contracts --save-dev

Permissions

Calling smart contract have to be granted permissions to call getAttributes in Mainnet. Contact us via email at [email protected] or Discord​
Testnets like Goerli,Mumbai,etc.. do not require any permissions

Function

QuadReader.sol
import "@quadrata/contracts/interfaces/IQuadPassportStore.sol";
​
// For Solidity version >= 0.8.0.
reader.getAttributes(
address user,
bytes32 attribute
) external payable returns(
IQuadPassportStore.Attribute[] memory attributes
);
​
​
// For Solidity version < 0.8.0.
reader.getAttributesLegacy(
address user,
bytes32 attribute
) external payable returns(
bytes32[] attributeValues,
uint256[] epochs,
address[] issuers
);

Parameters

Parameter
Description
Type
user
address of the passport holder
address (required)
attribute
The attribute you want to query. See: Supported attributes.
bytes32 (required)

Return values

A list of attributes that have been issued.
IQuadPassportStore.sol
/// @dev Attribute store infomation as it relates to a single attribute
/// `attrKeys` Array of keys defined by (wallet address/DID + data Type)
/// `value` Attribute value
/// `epoch` timestamp when the attribute has been verified by an Issuer
/// `issuer` address of the issuer issuing the attribute
struct Attribute {
bytes32 value;
uint256 epoch;
address issuer;
}
For Solidity version < 0.8.0
UsegetAttributesLegacy()which returns three arrays. The index of each array maps to the others to create a tuple (e.g. attributeValues[0], epochs[0], issuers[0] are part of the same result).
  • attributeValues: Raw or hashed attribute values. See Supported attributes for the return values of each attribute.
  • epochs: Timestamp that indicates when the attribute was verified by the passport issuer.
  • issuers: Passport issuer who verified the attributes.
​

Example

You can find our helper library to facilitate parsing the response => QuadReaderUtils​
import "@quadrata/contracts/interfaces/IQuadReader.sol";
import "@quadrata/contracts/interfaces/IQuadPassportStore.sol";
import "@quadrata/contracts/utility/QuadReaderUtils.sol";
​
contract MyDapp {
using QuadReaderUtils for bytes32;
IQuadReader public reader;
function borrowMoney() external payable {
IQuadPassportStore.Attribute[] memory attributes = reader.getAttributes(
msg.sender,
keccak256("COUNTRY")
);
​
require(attributes.length > 0, "REQUIRES_COUNTRY");
// only users residing outside the US may borrow money
if (!attributes[0].value.countryIsEqual("US")) {
// Allow borrow actions
}
}
​
​

​

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Last modified 7mo ago