Messenger

Variables

Message

struct Message {
    bytes32 txUniqueIdentification;
    bytes32 crossType;
    bytes32 srcAnchor;
    bytes bnExtraFeed;
    bytes32 dstAnchor;
    bytes payload;
}

A properly defined struct to pack essential cross-chain information.

Params

Name	Type	Description
txUniqueIdentification	bytes32	A globally unique identifier for each cross-chain message
crossType	bytes32	Indicate the type of a cross-chain message
srcAnchor	bytes32	The address of the source chain Anchor in bytes32
bnExtraFeed	bytes	Additional data that depends on the crossType
dstAnchor	bytes32	The address of the destination chain Anchor in bytes32
payload	bytes	Application-level data that will be forwarded to the destination consumer contract

MessageStatus

enum MessageStatus {
    DELIVERED,
    FAILED
}

Returns DELIVERED when the cross-chain message has been successfully delivered to the destination. Otherwise, FAILED is signalled, along with an event MessageCached emitted.

Events

MessageSent

event MessageSent(Message message);

Emits on the source chain with essential cross-chain information packed in a Message struct.

MessageReceived

event MessageReceived(
    bytes32 txUniqueIdentification,
    bytes32 crossType,
    bytes32 srcAnchor,
    bytes32 dstAnchor,
    MessageStatus status
);

Emits on the destination chain where the MessageStatus can be either DELIVERED or FAILED.

MessageCached

event MessageCached(bytes reason, bytes payload)

Emits when the destination transaction reverted for some reason. A bridge builder should define the error logic in their application-level contracts.

It can be combined with the corresponding MessageReceived event to recover the original message and identify the reverting reason.

Functions

sendToBool

function sendToBool(
    address payable refundAddress,
    bytes32 crossType,
    bytes memory valueFeed,
    uint32 dstChainId,
    bytes32 dstAnchor,
    bytes calldata payload
) external payable onlyRegisteredAnchor returns (bytes32 txUniqueIdentification)

Called by registered Anchors to forward cross-chain messages to BOOLNetwork.

Params

Name	Type	Description
refundAddress	address payable	The address to receive the rest of the pre-paid transaction fee
crossType	bytes32	Indicate the type of a cross-chain message
valueFeed	bytes	Additional data that depends on the crossType
dstChainId	uint32	ID of the destination chain
dstAnchor	bytes32	The address of the destination chain Anchor in bytes32
payload	bytes	Application-level data that will be forwarded to the destination consumer contract

Return Values

Name	Type	Description
txUniqueIdentification	bytes32	A globally unique identifier for each cross-chain message

receiveFromBool

function receiveFromBool(
    Message memory message, 
    bytes calldata signature
)external payable returns (MessageStatus status)

Receives cross-chain messages from BOOLNetwork.

Params

Name	Type	Description
message	Message	A Message struct consists of all the essential cross-chain information
signature	bytes	Signature from a committee which is used to verify the validity of a cross-chain message

Return Values

Name	Type	Description
status	MessageStatus	An identifier to present the final status of a cross-chain message