CFAv1Forwarder

The CFAv1Forwarder contract is a Superfluid forwarder that implements the Constant Flow Agreement (CFA) related functions. It is a contract specifically made immutable in order to facilitate the interaction with Money Streaming through the Constant Flow Agreement (CFA).

This contract is optimized for interaction that would happen from outside the blockchain (off-chain). For more information on the best practices regarding this interaction, please refer to the Interact Off-Chain section of this documentation.

ABI

In order to interact with the CFAv1Forwarder contract, you can use the following ABI:

Click here to show CFAv1Forwarder ABI

[
  {
    "inputs": [
      {
        "internalType": "contract ISuperfluid",
        "name": "host",
        "type": "address"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "constructor"
  },
  { "inputs": [], "name": "CFA_FWD_INVALID_FLOW_RATE", "type": "error" },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" },
      { "internalType": "bytes", "name": "userData", "type": "bytes" }
    ],
    "name": "createFlow",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" },
      { "internalType": "bytes", "name": "userData", "type": "bytes" }
    ],
    "name": "deleteFlow",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "account", "type": "address" }
    ],
    "name": "getAccountFlowInfo",
    "outputs": [
      { "internalType": "uint256", "name": "lastUpdated", "type": "uint256" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" },
      { "internalType": "uint256", "name": "deposit", "type": "uint256" },
      { "internalType": "uint256", "name": "owedDeposit", "type": "uint256" }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
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        "type": "address"
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      { "internalType": "address", "name": "account", "type": "address" }
    ],
    "name": "getAccountFlowrate",
    "outputs": [
      { "internalType": "int96", "name": "flowrate", "type": "int96" }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "int96", "name": "flowrate", "type": "int96" }
    ],
    "name": "getBufferAmountByFlowrate",
    "outputs": [
      { "internalType": "uint256", "name": "bufferAmount", "type": "uint256" }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" }
    ],
    "name": "getFlowInfo",
    "outputs": [
      { "internalType": "uint256", "name": "lastUpdated", "type": "uint256" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" },
      { "internalType": "uint256", "name": "deposit", "type": "uint256" },
      { "internalType": "uint256", "name": "owedDeposit", "type": "uint256" }
    ],
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    "type": "function"
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  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "flowOperator", "type": "address" }
    ],
    "name": "getFlowOperatorPermissions",
    "outputs": [
      { "internalType": "uint8", "name": "permissions", "type": "uint8" },
      { "internalType": "int96", "name": "flowrateAllowance", "type": "int96" }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" }
    ],
    "name": "getFlowrate",
    "outputs": [
      { "internalType": "int96", "name": "flowrate", "type": "int96" }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "flowOperator", "type": "address" }
    ],
    "name": "grantPermissions",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
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  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "flowOperator", "type": "address" }
    ],
    "name": "revokePermissions",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "receiver", "type": "address" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" }
    ],
    "name": "setFlowrate",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" }
    ],
    "name": "setFlowrateFrom",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "sender", "type": "address" },
      { "internalType": "address", "name": "receiver", "type": "address" },
      { "internalType": "int96", "name": "flowrate", "type": "int96" },
      { "internalType": "bytes", "name": "userData", "type": "bytes" }
    ],
    "name": "updateFlow",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "contract ISuperToken",
        "name": "token",
        "type": "address"
      },
      { "internalType": "address", "name": "flowOperator", "type": "address" },
      { "internalType": "uint8", "name": "permissions", "type": "uint8" },
      { "internalType": "int96", "name": "flowrateAllowance", "type": "int96" }
    ],
    "name": "updateFlowOperatorPermissions",
    "outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  }
]

CFA_FWD_INVALID_FLOW_RATE

error CFA_FWD_INVALID_FLOW_RATE()

_cfa

contract IConstantFlowAgreementV1 _cfa

Fn constructor

function constructor(
    contract ISuperfluid host
)
    public

Parameters

Name	Type	Description
host	contract ISuperfluid

Fn setFlowrate

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
receiver	address	The receiver of the flow
flowrate	int96	The wanted flowrate in wad/second. Only positive values are valid here.

Return Values

Name	Type	Description
[0]	bool	bool

Sets the given flowrate between msg.sender and a given receiver. If there's no pre-existing flow and flowrate non-zero, a new flow is created. If there's an existing flow and flowrate non-zero, the flowrate of that flow is updated. If there's an existing flow and flowrate zero, the flow is deleted. If the existing and given flowrate are equal, no action is taken. On creation of a flow, a "buffer" amount is automatically detracted from the sender account's available balance. If the sender account is solvent when the flow is deleted, this buffer is redeemed to it.

Fn setFlowrateFrom

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	The sender of the flow
receiver	address	The receiver of the flow
flowrate	int96	The wanted flowrate in wad/second. Only positive values are valid here.

Return Values

Name	Type	Description
[0]	bool	bool

Like setFlowrate, but can be invoked by an account with flowOperator permissions on behalf of the sender account.

Fn getFlowrate

Currently, only 0 or 1 flows can exist between 2 accounts. This may change in the future.

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	The sender of the flow
receiver	address	The receiver of the flow

Return Values

Name	Type	Description
flowrate	int96	The flowrate from the sender to the receiver account. Returns 0 if no flow exists.

Get the flowrate of the flow between 2 accounts if exists.

Fn getFlowInfo

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	The sender of the flow
receiver	address	The receiver of the flow

Return Values

Name	Type	Description
lastUpdated	uint256	Timestamp of last update (flowrate change) or zero if no flow exists
flowrate	int96	Current flowrate of the flow or zero if no flow exists
deposit	uint256	Deposit amount locked as security buffer during the lifetime of the flow
owedDeposit	uint256	Extra deposit amount borrowed to a SuperApp receiver by the flow sender

Get all available information about a flow (if exists). If only the flowrate is needed, consider using getFlowrate instead.

Fn getBufferAmountByFlowrate

function getBufferAmountByFlowrate(
    contract ISuperToken token,
    int96 flowrate
)
    external
    returns (uint256 bufferAmount)

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
flowrate	int96	The flowrate for which the buffer amount is calculated

Return Values

Name	Type	Description
bufferAmount	uint256	The buffer amount required for the given configuration.

Get the buffer amount required for the given token and flowrate. This amount can vary based on the combination of token, flowrate and chain being queried. The result for a given set of parameters can change over time, because it depends on governance configurable protocol parameters. Changes of the required buffer amount affect only flows created or updated after the change.

Fn getAccountFlowrate

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
account	address	Account to query

Return Values

Name	Type	Description
flowrate	int96	The net flowrate (aggregate incoming minus aggregate outgoing flowrate), can be negative.

Get the net flowrate of an account.

Fn getAccountFlowInfo

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
account	address	Account to query

Return Values

Name	Type	Description
lastUpdated	uint256	Timestamp of last update of a flow to or from the account (flowrate change)
flowrate	int96	Current net aggregate flowrate
deposit	uint256	Aggregate deposit amount currently locked as security buffer for outgoing flows
owedDeposit	uint256	Aggregate extra deposit amount currently borrowed to SuperApps receiving from this account

Get aggregated flow information (if any exist) of an account. If only the net flowrate is needed, consider using getAccountFlowrate instead.

Fn createFlow

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	Sender address of the flow
receiver	address	Receiver address of the flow
flowrate	int96	The flowrate in wad/second to be set initially
userData	bytes	(optional) User data to be set. Should be set to zero if not needed.

Return Values

Name	Type	Description
[0]	bool	bool

Low-level wrapper of createFlow/createFlowByOperator. If the address of msg.sender is not the same as the address of the sender argument, createFlowByOperator is used internally. In this case msg.sender needs to have permission to create flows on behalf of the given sender account with sufficient flowRateAllowance. Currently, only 1 flow can exist between 2 accounts, thus createFlow will fail if one already exists.

Fn updateFlow

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	Sender address of the flow
receiver	address	Receiver address of the flow
flowrate	int96	The flowrate in wad/second the flow should be updated to
userData	bytes	(optional) User data to be set. Should be set to zero if not needed.

Return Values

Name	Type	Description
[0]	bool	bool

Low-level wrapper if updateFlow/updateFlowByOperator. If the address of msg.sender doesn't match the address of the sender argument, updateFlowByOperator is invoked. In this case msg.sender needs to have permission to update flows on behalf of the given sender account with sufficient flowRateAllowance.

Fn deleteFlow

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	Sender address of the flow
receiver	address	Receiver address of the flow
userData	bytes	(optional) User data to be set. Should be set to zero if not needed.

Return Values

Name	Type	Description
[0]	bool	bool

Low-level wrapper of deleteFlow/deleteFlowByOperator. If msg.sender isn't the same as sender address, msg.sender needs to have permission to delete flows on behalf of the given sender account.

Fn grantPermissions

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
flowOperator	address	Account to which permissions are granted

Return Values

Name	Type	Description
[0]	bool	bool

Grants a flowOperator permission to create/update/delete flows on behalf of msg.sender. In order to restrict what a flowOperator can or can't do, the flowOperator account should be a contract implementing the desired restrictions.

Fn revokePermissions

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
flowOperator	address	Account from which permissions are revoked

Return Values

Name	Type	Description
[0]	bool	bool

Revokes all permissions previously granted to a flowOperator by msg.sender. Revocation doesn't undo or reset flows previously created/updated by the flowOperator. In order to be sure about the state of flows at the time of revocation, you need to check that state either in the same transaction or after this transaction.

Fn updateFlowOperatorPermissions

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
flowOperator	address	Account for which permissions are set on behalf of msg.sender
permissions	uint8	Bitmask for create/update/delete permission flags. See library FlowOperatorDefinitions
flowrateAllowance	int96	Max. flowrate in wad/second the operator can set for individual flows.

Return Values

Name	Type	Description
[0]	bool	bool

Low-level wrapper of IConstantFlowAgreementV1.updateFlowOperatorPermissions flowrateAllowance does NOT restrict the net flowrate a flowOperator is able to set. In order to restrict that, flowOperator needs to be a contract implementing the wanted limitations.

Fn getFlowOperatorPermissions

Parameters

Name	Type	Description
token	contract ISuperToken	Super token address
sender	address	The account which (possiby) granted permissions
flowOperator	address	Account to which (possibly) permissions were granted

Return Values

Name	Type	Description
permissions	uint8	A bitmask of the permissions currently granted (or not) by sender to flowOperator
flowrateAllowance	int96	Max. flowrate in wad/second the flowOperator can set for individual flows.

Get the currently set permissions granted to the given flowOperator by the given sender account.

Fn _setFlowrateFrom

Parameters

Name	Type	Description
token	contract ISuperToken
sender	address
receiver	address
flowrate	int96

Fn _createFlow

Parameters

Name	Type	Description
token	contract ISuperToken
sender	address
receiver	address
flowrate	int96
userData	bytes

Fn _updateFlow

Parameters

Name	Type	Description
token	contract ISuperToken
sender	address
receiver	address
flowrate	int96
userData	bytes

Fn _deleteFlow

Parameters

Name	Type	Description
token	contract ISuperToken
sender	address
receiver	address
userData	bytes

Fn _updateFlowOperatorPermissions

Parameters

Name	Type	Description
token	contract ISuperToken
flowOperator	address
permissions	uint8
flowrateAllowance	int96