Unlocking the Secrets of .rev* Files on Ethereum
Ethereum, a decentralized platform for building smart contracts and decentralized applications (dApps), uses various file formats to store and transfer data. One such format is .rev, which stands for “revocation” and is used to store revocation information for ERC-721 non-fungible tokens (NFTs). In this article, we’ll dive into the world of .rev files and explore what they contain.
The Structure of a .rev* File
A typical .rev* file consists of an array with [F9BEB4D9 + 32-byte number + variable raw data] for each element. Here’s a breakdown of what that might look like:
[F9BEB4D9, 32byte_number, var_raw_data]
The first part, F9BEB4D9, is the magic number that identifies the file type. It is not used directly in the data, but serves as a unique identifier.
The second field, 32byte_number, represents an optional timestamp of when the revocation was recorded. This can be useful for auditing purposes or tracking revocation history.
The variable raw data
The third field, var_raw_data, contains variable raw data that can include metadata such as:
hash: a unique identifier for the NFT
metadata: additional information about the NFT (e.g. creator, description)
transaction_hash: a hash of a transaction that created or updated the NFT
This variable raw data is not strictly required and can be omitted if needed. However, it is important to note that omitting this field can result in inconsistent revocation records.
Additional information
It is worth noting that .rev* files are stored on-chain, meaning they are part of the Ethereum blockchain. They contain a specific set of rules for creating and managing these records.
Conclusion
In summary, .rev files on Ethereum provide a convenient way to store and manage revocation information for NFTs. While the structure is straightforward, it is important to understand the context in which these files are used. If you are developing an application that interacts with ERC-721 NFTs or needs access to this data, becoming familiar with the .rev file format can streamline your development process.
Code example
Here is a simplified example of what a .rev* file might look like in Rust:
use eth_types::{Hash, U256};
struct Revocation {
timestamp: u64,
hash: Hash,
metadata: [u8; 1024], // variable raw data (optional)
}
impl Revocation {
fn new(timestamp: u64, hash: Hash) -> Self {
Revocation { timestamp, hash }
}
}
Keep in mind that this is a highly simplified example and the actual implementation may vary depending on the specific needs of your project.
I hope this article helped you understand more about .rev* files on Ethereum. If you have any further questions or need clarification on any aspect of this topic, feel free to ask!