local_verify 0.1.12

A Library containing utilities for the local verification of merkle tree response obtained from the managed verifier canister
Documentation 
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use rs_merkle::{algorithms::Sha256, Hasher, MerkleTree};

/// Generate a merkle tree by providing the leaves as hashed strings
pub fn generate_merkle_tree(leaves: &Vec<[u8; 32]>) -> MerkleTree<Sha256> {
    let tree: MerkleTree<Sha256> = MerkleTree::<Sha256>::from_leaves(&leaves);
    return tree;
}

/// Validate that the provided root hash is the same as the one derived from building a tree out of the provided leaves
pub fn validate_merkle_tree(leaves: &Vec<String>, root_hash: &String) -> bool {
    // gather the leaves from the content of the verified proof
    // which is either the req/res pair or the has of the session proof
    let leaves: Vec<[u8; 32]> = leaves
        .iter()
        .map(|proof_response| {
            let proof_byte_content = proof_response.as_bytes();

            Sha256::hash(proof_byte_content)
        })
        .collect();

    let merkle_tree = generate_merkle_tree(&leaves);

    let root = merkle_tree.root().unwrap();
    let derived_root_hash = hex::encode(root);
    let root_hash = root_hash.to_owned();

    println!("derived_root_hash: {}", derived_root_hash);
    println!("root_hash: {}", root_hash);

    return derived_root_hash == root_hash;
}