Backend Price Provider

Backend price verifier.

Methods

DEFAULT_ADMIN_ROLE

function DEFAULT_ADMIN_ROLE() external view returns (bytes32)

Returns

Name	Type	Description
_0	bytes32	undefined

DESCRIPTION

function DESCRIPTION() external view returns (string)

Returns

Name	Type	Description
_0	string	undefined

TRUSTED_BACKEND_ROLE

function TRUSTED_BACKEND_ROLE() external view returns (bytes32)

Returns

Name	Type	Description
_0	bytes32	undefined

backendMetadata

function backendMetadata(address) external view returns (bool isListed, bool isActive)

Parameters

Name	Type	Description
_0	address	undefined

Returns

Name	Type	Description
isListed	bool	undefined
isActive	bool	undefined

changeActive

function changeActive(address token, bool active) external nonpayable

Parameters

Name	Type	Description
token	address	undefined
active	bool	undefined

getEthSignedMessageHash

function getEthSignedMessageHash(bytes32 messageHash) external pure returns (bytes32)

1. step. Backend formatting the message and get hash of this message.

returns the keccak256 of formatted message

Parameters

Name	Type	Description
messageHash	bytes32	the keccak256 of message

Returns

Name	Type	Description
_0	bytes32	undefined

getEvaluation

function getEvaluation(address token, uint256 tokenAmount) external pure returns (uint256 evaluation)

Parameters

Name	Type	Description
token	address	undefined
tokenAmount	uint256	undefined

Returns

Name	Type	Description
evaluation	uint256	undefined

getEvaluationSigned

function getEvaluationSigned(address token, uint256 tokenAmount, uint256 priceMantissa, uint256 validTo, bytes signature) external view returns (uint256 evaluation)

return the evaluation in $ of tokenAmount with signed price

Parameters

Name	Type	Description
token	address	the address of token to get evaluation in $
tokenAmount	uint256	the amount of token to get evaluation. Amount is scaled by 10 in power token decimals
priceMantissa	uint256	the price multiplied by priceDecimals. The dimension of priceMantissa should be $/token
validTo	uint256	the timestamp in seconds, when price is gonna be not valid.
signature	bytes	the ECDSA sign on eliptic curve secp256k1.

Returns

Name	Type	Description
evaluation	uint256	undefined

getMessageHash

function getMessageHash(address token, uint256 priceMantissa, uint256 validTo) external pure returns (bytes32)

1. step. Backend creates offchain data and get hash of this data. This data calls message.

returns the keccak256 of concatenated input data

Parameters

Name	Type	Description
token	address	the address of asset
priceMantissa	uint256	the price of asset that include decimals
validTo	uint256	the unix timestamp in seconds that define the validity of given price to validTo timestamp

Returns

Name	Type	Description
_0	bytes32	undefined

getPrice

function getPrice(address token) external pure returns (uint256 price, uint8 priceDecimals)

Returns the latest asset price and price decimals

Parameters

Name	Type	Description
token	address	the token address

Returns

Name	Type	Description
price	uint256	undefined
priceDecimals	uint8	undefined

getPriceDecimals

function getPriceDecimals() external view returns (uint8)

Returns

Name	Type	Description
_0	uint8	undefined

getPriceSigned

function getPriceSigned(address token, uint256 priceMantissa, uint256 validTo, bytes signature) external view returns (uint256 _priceMantissa, uint8 priceDecimals)

Parameters

Name	Type	Description
token	address	undefined
priceMantissa	uint256	undefined
validTo	uint256	undefined
signature	bytes	undefined

Returns

Name	Type	Description
_priceMantissa	uint256	undefined
priceDecimals	uint8	undefined

getRoleAdmin

function getRoleAdmin(bytes32 role) external view returns (bytes32)

Returns the admin role that controls role. See {grantRole} and {revokeRole}. To change a role's admin, use {_setRoleAdmin}.

Parameters

Name	Type	Description
role	bytes32	undefined

Returns

Name	Type	Description
_0	bytes32	undefined

grandTrustedBackendRole

function grandTrustedBackendRole(address newTrustedBackend) external nonpayable

Parameters

Name	Type	Description
newTrustedBackend	address	undefined

grantRole

function grantRole(bytes32 role, address account) external nonpayable

Grants role to account. If account had not been already granted role, emits a {RoleGranted} event. Requirements: - the caller must have role's admin role.

Parameters

Name	Type	Description
role	bytes32	undefined
account	address	undefined

hasRole

function hasRole(bytes32 role, address account) external view returns (bool)

Returns true if account has been granted role.

Parameters

Name	Type	Description
role	bytes32	undefined
account	address	undefined

Returns

Name	Type	Description
_0	bool	undefined

initialize

function initialize() external nonpayable

isActive

function isActive(address token) external view returns (bool)

Parameters

Name	Type	Description
token	address	undefined

Returns

Name	Type	Description
_0	bool	undefined

isListed

function isListed(address token) external view returns (bool)

Parameters

Name	Type	Description
token	address	undefined

Returns

Name	Type	Description
_0	bool	undefined

recoverSigner

function recoverSigner(bytes32 ethSignedMessageHash, bytes signature) external pure returns (address)

returns the signer of ethSignedMessageHash

Parameters

Name	Type	Description
ethSignedMessageHash	bytes32	undefined
signature	bytes	undefined

Returns

Name	Type	Description
_0	address	undefined

renounceRole

function renounceRole(bytes32 role, address account) external nonpayable

Revokes role from the calling account. Roles are often managed via {grantRole} and {revokeRole}: this function's purpose is to provide a mechanism for accounts to lose their privileges if they are compromised (such as when a trusted device is misplaced). If the calling account had been granted role, emits a {RoleRevoked} event. Requirements: - the caller must be account.

Parameters

Name	Type	Description
role	bytes32	undefined
account	address	undefined

revokeRole

function revokeRole(bytes32 role, address account) external nonpayable

Revokes role from account. If account had been granted role, emits a {RoleRevoked} event. Requirements: - the caller must have role's admin role.

Parameters

Name	Type	Description
role	bytes32	undefined
account	address	undefined

revokeTrustedBackendRole

function revokeTrustedBackendRole(address trustedBackend) external nonpayable

Parameters

Name	Type	Description
trustedBackend	address	undefined

setToken

function setToken(address token) external nonpayable

Parameters

Name	Type	Description
token	address	undefined

supportsInterface

function supportsInterface(bytes4 interfaceId) external view returns (bool)

See {IERC165-supportsInterface}.

Parameters

Name	Type	Description
interfaceId	bytes4	undefined

Returns

Name	Type	Description
_0	bool	undefined

usdDecimals

function usdDecimals() external view returns (uint8)

Returns

Name	Type	Description
_0	uint8	undefined

verify

function verify(address token, uint256 priceMantissa, uint256 validTo, bytes signature) external view returns (bool)

1. step. Smart contract verify the message (tuple)

returns true if the message is signed by trusted backend. Else returns false.

Parameters

Name	Type	Description
token	address	the address of asset
priceMantissa	uint256	the price of asset that include decimals
validTo	uint256	the unix timestamp in seconds that define the validity of given price to validTo timestamp
signature	bytes	the sign of message.

Returns

Name	Type	Description
_0	bool	undefined

Events

ChangeActive

event ChangeActive(address indexed who, address indexed token, bool active)

Parameters

Name	Type	Description
who indexed	address	undefined
token indexed	address	undefined
active	bool	undefined

GrandTrustedBackendRole

event GrandTrustedBackendRole(address indexed who, address indexed newTrustedBackend)

Parameters

Name	Type	Description
who indexed	address	undefined
newTrustedBackend indexed	address	undefined

RevokeTrustedBackendRole

event RevokeTrustedBackendRole(address indexed who, address indexed trustedBackend)

Parameters

Name	Type	Description
who indexed	address	undefined
trustedBackend indexed	address	undefined

RoleAdminChanged

event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole)

Parameters

Name	Type	Description
role indexed	bytes32	undefined
previousAdminRole indexed	bytes32	undefined
newAdminRole indexed	bytes32	undefined

RoleGranted

event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender)

Parameters

Name	Type	Description
role indexed	bytes32	undefined
account indexed	address	undefined
sender indexed	address	undefined

RoleRevoked

event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender)

Parameters

Name	Type	Description
role indexed	bytes32	undefined
account indexed	address	undefined
sender indexed	address	undefined

SetToken

event SetToken(address indexed who, address indexed token)

Parameters

Name	Type	Description
who indexed	address	undefined
token indexed	address	undefined