# MessageBus

## Methods

### authVerifier

```solidity
function authVerifier() external view returns (address)
```

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | address | undefined   |

### computeMessageId

```solidity
function computeMessageId(address _srcAddress, uint256 _srcChainId, bytes32 _dstAddress, uint256 _dstChainId, uint256 _srcNonce, bytes _message) external view returns (bytes32)
```

#### Parameters

| Name         | Type    | Description |
| ------------ | ------- | ----------- |
| \_srcAddress | address | undefined   |
| \_srcChainId | uint256 | undefined   |
| \_dstAddress | bytes32 | undefined   |
| \_dstChainId | uint256 | undefined   |
| \_srcNonce   | uint256 | undefined   |
| \_message    | bytes   | undefined   |

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | bytes32 | undefined   |

### estimateFee

```solidity
function estimateFee(uint256 _dstChainId, bytes _options) external nonpayable returns (uint256)
```

#### Parameters

| Name         | Type    | Description |
| ------------ | ------- | ----------- |
| \_dstChainId | uint256 | undefined   |
| \_options    | bytes   | undefined   |

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | uint256 | undefined   |

### executeMessage

```solidity
function executeMessage(uint256 _srcChainId, bytes32 _srcAddress, address _dstAddress, uint256 _gasLimit, uint256 _nonce, bytes _message, bytes32 _messageId) external nonpayable
```

Relayer executes messages through an authenticated method to the destination receiver based on the originating transaction on source chain

#### Parameters

| Name         | Type    | Description                                                                                                             |
| ------------ | ------- | ----------------------------------------------------------------------------------------------------------------------- |
| \_srcChainId | uint256 | Originating chain ID - typically a standard EVM chain ID, but may refer to a Synapse-specific chain ID on nonEVM chains |
| \_srcAddress | bytes32 | Originating bytes32 address of the message sender on the srcChain                                                       |
| \_dstAddress | address | Destination address that the arbitrary message will be passed to                                                        |
| \_gasLimit   | uint256 | Gas limit to be passed alongside the message, depending on the fee paid on srcChain                                     |
| \_nonce      | uint256 | undefined                                                                                                               |
| \_message    | bytes   | Arbitrary message payload to pass to the destination chain receiver                                                     |
| \_messageId  | bytes32 | undefined                                                                                                               |

### fees

```solidity
function fees() external view returns (uint256)
```

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | uint256 | undefined   |

### gasFeePricing

```solidity
function gasFeePricing() external view returns (address)
```

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | address | undefined   |

### getExecutedMessage

```solidity
function getExecutedMessage(bytes32 _messageId) external view returns (enum MessageBusReceiver.TxStatus)
```

#### Parameters

| Name        | Type    | Description |
| ----------- | ------- | ----------- |
| \_messageId | bytes32 | undefined   |

#### Returns

| Name | Type                             | Description |
| ---- | -------------------------------- | ----------- |
| \_0  | enum MessageBusReceiver.TxStatus | undefined   |

### nonce

```solidity
function nonce() external view returns (uint64)
```

#### Returns

| Name | Type   | Description |
| ---- | ------ | ----------- |
| \_0  | uint64 | undefined   |

### owner

```solidity
function owner() external view returns (address)
```

*Returns the address of the current owner.*

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | address | undefined   |

### renounceOwnership

```solidity
function renounceOwnership() external nonpayable
```

*Leaves the contract without owner. It will not be possible to call `onlyOwner` functions anymore. Can only be called by the current owner. NOTE: Renouncing ownership will leave the contract without an owner, thereby removing any functionality that is only available to the owner.*

### rescueGas

```solidity
function rescueGas(address payable to) external nonpayable
```

Rescues any gas in contract, aside from fees

#### Parameters

| Name | Type            | Description                       |
| ---- | --------------- | --------------------------------- |
| to   | address payable | Address to which to rescue gas to |

### sendMessage

```solidity
function sendMessage(bytes32 _receiver, uint256 _dstChainId, bytes _message, bytes _options) external payable
```

Sends a message to a receiving contract address on another chain. Sender must make sure that the message is unique and not a duplicate message.

#### Parameters

| Name         | Type    | Description                                                                               |
| ------------ | ------- | ----------------------------------------------------------------------------------------- |
| \_receiver   | bytes32 | The bytes32 address of the destination contract to be called                              |
| \_dstChainId | uint256 | The destination chain ID - typically, standard EVM chain ID, but differs on nonEVM chains |
| \_message    | bytes   | The arbitrary payload to pass to the destination chain receiver                           |
| \_options    | bytes   | Versioned struct used to instruct relayer on how to proceed with gas limits               |

### transferOwnership

```solidity
function transferOwnership(address newOwner) external nonpayable
```

*Transfers ownership of the contract to a new account (`newOwner`). Can only be called by the current owner.*

#### Parameters

| Name     | Type    | Description |
| -------- | ------- | ----------- |
| newOwner | address | undefined   |

### updateAuthVerifier

```solidity
function updateAuthVerifier(address _authVerifier) external nonpayable
```

#### Parameters

| Name           | Type    | Description |
| -------------- | ------- | ----------- |
| \_authVerifier | address | undefined   |

### updateGasFeePricing

```solidity
function updateGasFeePricing(address _gasFeePricing) external nonpayable
```

#### Parameters

| Name            | Type    | Description |
| --------------- | ------- | ----------- |
| \_gasFeePricing | address | undefined   |

### updateMessageStatus

```solidity
function updateMessageStatus(bytes32 _messageId, enum MessageBusReceiver.TxStatus _status) external nonpayable
```

CONTRACT CONFIG

#### Parameters

| Name        | Type                             | Description |
| ----------- | -------------------------------- | ----------- |
| \_messageId | bytes32                          | undefined   |
| \_status    | enum MessageBusReceiver.TxStatus | undefined   |

### withdrawGasFees

```solidity
function withdrawGasFees(address payable to) external nonpayable
```

Withdraws accumulated fees in native gas token, based on fees variable.

#### Parameters

| Name | Type            | Description                                                                                           |
| ---- | --------------- | ----------------------------------------------------------------------------------------------------- |
| to   | address payable | Address to withdraw gas fees to, which can be specified in the event owner() can't receive native gas |

## Events

### CallReverted

```solidity
event CallReverted(string reason)
```

#### Parameters

| Name   | Type   | Description |
| ------ | ------ | ----------- |
| reason | string | undefined   |

### Executed

```solidity
event Executed(bytes32 indexed messageId, enum MessageBusReceiver.TxStatus status, address indexed _dstAddress, uint64 srcChainId, uint64 srcNonce)
```

#### Parameters

| Name                   | Type                             | Description |
| ---------------------- | -------------------------------- | ----------- |
| messageId `indexed`    | bytes32                          | undefined   |
| status                 | enum MessageBusReceiver.TxStatus | undefined   |
| \_dstAddress `indexed` | address                          | undefined   |
| srcChainId             | uint64                           | undefined   |
| srcNonce               | uint64                           | undefined   |

### MessageSent

```solidity
event MessageSent(address indexed sender, uint256 srcChainID, bytes32 receiver, uint256 indexed dstChainId, bytes message, uint64 nonce, bytes options, uint256 fee, bytes32 indexed messageId)
```

#### Parameters

| Name                 | Type    | Description |
| -------------------- | ------- | ----------- |
| sender `indexed`     | address | undefined   |
| srcChainID           | uint256 | undefined   |
| receiver             | bytes32 | undefined   |
| dstChainId `indexed` | uint256 | undefined   |
| message              | bytes   | undefined   |
| nonce                | uint64  | undefined   |
| options              | bytes   | undefined   |
| fee                  | uint256 | undefined   |
| messageId `indexed`  | bytes32 | undefined   |

### OwnershipTransferred

```solidity
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner)
```

#### Parameters

| Name                    | Type    | Description |
| ----------------------- | ------- | ----------- |
| previousOwner `indexed` | address | undefined   |
| newOwner `indexed`      | address | undefined   |


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