tchain 0.1.3

A blockchain using proof of selection for mining
Documentation 
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pub use super::block::*;

unsafe impl lmdb::traits::LmdbRaw for Block<'static> {}
unsafe impl lmdb::traits::LmdbRaw for BlockHeader {}
unsafe impl lmdb::traits::LmdbOrdKey for Block<'static> {}

impl Blockchain<'_> {
    ///
    /// Gets the last block mined from the network
    /// and checks to see if ut is already saved.
    /// If not saved, will grab from peer in
    /// peer list
    ///
    pub fn get_tip(&self) {
        // Check network for current block
    }
}

///
/// Read blockchain from file and load
/// into hashmap
///
pub fn init_blockchain(db_name: &'static str) -> Result<Blockchain, lmdb::Error> {
    // Get handle to blockchain db
    let db: lmdb::Database = get_lmdb_connection(db_name)?;

    // Create read transaction for getting blocks
    let tx = lmdb::ReadTransaction::new(db.env())?;

    // Initialize blockchain structure
    let blockchain = Blockchain::default();

    // Create cursor and put on last database entry
    let _curs = tx.cursor(&db).unwrap();

    // Assign accessor to database
    let _access = tx.access();

    // Get last block saved in database
    //   let last_block: &Block = curs.last::<str, Block>(&access)?.1;
    //   {
    //       blockchain.tip = *last_block;
    //   }

    Ok(blockchain)
}

///
/// Creates a file for storing the blockchain
/// database
///
pub fn get_lmdb_connection(env: &'static str) -> Result<lmdb::Database, lmdb::Error> {
    // Create directory for lmdb
    std::fs::create_dir_all(env).unwrap();

    // Setup lmdb enviornment
    let db_env: lmdb::Environment =
        unsafe { lmdb::EnvBuilder::new()?.open(&env, lmdb::open::Flags::empty(), 0o600)? };

    // Set Database options
    let ops = lmdb::DatabaseOptions::create_map::<Block>();

    // Open database
    let db: lmdb::Database = lmdb::Database::open(db_env, None, &ops)?;

    // Return database handle
    Ok(db)
}