structs.sol

Overview

This Solidity source file defines a simple data structure named MessageInfo. Its primary purpose is to encapsulate key information about a message, specifically a hashed identifier and an expiration timestamp. This struct can be used throughout the smart contract system to standardize message metadata handling, enabling consistent storage, retrieval, and verification of message-related data.

Structs

MessageInfo

Description

MessageInfo is a struct that groups two pieces of data related to a message:

• messageHash (uint256): A unique hash representing the message content or identifier.

• expireAt (uint32): A timestamp (likely in Unix epoch format) indicating when the message expires or becomes invalid.

Fields

Usage Example

// Example of initializing a MessageInfo struct
MessageInfo memory msgInfo = MessageInfo({
    messageHash: uint256(keccak256(abi.encodePacked("Hello World"))),
    expireAt: uint32(block.timestamp + 3600) // Expires in 1 hour
});

This struct can be used in mappings, arrays, or function parameters to track message validity and identification efficiently.

Implementation Details

• The messageHash uses a uint256 type, which aligns with the size of hashes generated by common hashing functions like keccak256. This choice ensures compatibility with cryptographic hash outputs.

• The expireAt uses a uint32 type, which can represent timestamps up to the year 2106 when using Unix time. This is a space-efficient choice given typical blockchain timestamp ranges.

• The struct does not include any methods or functions, making it a pure data container in line with Solidity’s struct usage patterns.

Interaction with Other System Components

• The MessageInfo struct is likely used in other contracts or modules that handle message verification, lifecycle management, or storage. For example, it could be part of a message queue, event log, or message validation mechanism.

• Since the file contains only the struct definition, it serves as a foundational building block imported or referenced by other Solidity files within the project. Its simple interface allows for flexible integration with various contract functions that require message metadata.

• The messageHash may interact with cryptographic verification procedures, while expireAt provides temporal constraints enforced by contract logic.

Diagram: Structure of structs.sol

classDiagram
class MessageInfo {
+uint256 messageHash
+uint32 expireAt
}

This diagram represents the single struct defined in the file, highlighting its two data fields.