example: WIP DAO proposal process.

Cargo.toml

@@ -225,6 +225,11 @@ name = "tx"
 path = "example/tx.rs"
 required-features = ["node"]
 
+[[example]]
+name = "dao-process"
+path = "example/dao_process.rs"
+required-features = ["crypto", "zkas"]
+
 # ZK VM Proof examples
 
 [[example]]

example/dao_process.rs

@@ -0,0 +1,120 @@
+use halo2_gadgets::primitives::{
+    poseidon,
+    poseidon::{ConstantLength, P128Pow5T3},
+};
+use incrementalmerkletree::{bridgetree::BridgeTree, Frontier, Tree};
+use pasta_curves::{
+    arithmetic::CurveAffine,
+    group::{
+        ff::{Field, PrimeField},
+        Curve, Group,
+    },
+    pallas,
+};
+use rand::rngs::OsRng;
+use simplelog::{ColorChoice::Auto, Config, LevelFilter, TermLogger, TerminalMode::Mixed};
+
+use darkfi::{
+    crypto::{keypair::Keypair, merkle_node::MerkleNode, schnorr::SchnorrSecret},
+    Result,
+};
+
+fn main() -> Result<()> {
+    let loglevel = match option_env!("RUST_LOG") {
+        Some("debug") => LevelFilter::Debug,
+        Some("trace") => LevelFilter::Trace,
+        Some(_) | None => LevelFilter::Info,
+    };
+    TermLogger::init(loglevel, Config::default(), Mixed, Auto)?;
+
+    // =============
+    // Initial state
+    // =============
+
+    // We have a Merkle tree of some DAO treasuries
+    let mut tree = BridgeTree::<MerkleNode, 32>::new(100);
+    for _ in 0..3 {
+        let some_dao = pallas::Base::random(&mut OsRng);
+        tree.append(&MerkleNode(some_dao));
+    }
+
+    // And we have our DAO
+    let dao_authority = Keypair::random(&mut OsRng);
+
+    let spend_contract = pallas::Base::random(&mut OsRng);
+    let current_balance = pallas::Base::from(666);
+    let current_serial = pallas::Base::random(&mut OsRng);
+    let current_dao_blind = pallas::Base::random(&mut OsRng);
+
+    let message = [spend_contract, current_balance, current_serial, current_dao_blind];
+    let hasher = poseidon::Hash::<_, P128Pow5T3, ConstantLength<4>, 3, 2>::init();
+    let our_dao = hasher.hash(message);
+
+    tree.append(&MerkleNode(our_dao));
+    tree.witness();
+
+    // ========
+    // Proposal
+    // ========
+
+    // We make a proposal to send funds to some public key with the following
+    // parameters:
+    let amount_to_send = pallas::Base::from(42);
+    let destination = pallas::Point::random(&mut OsRng);
+    let destination_coords = destination.to_affine().coordinates().unwrap();
+    let proposal_blind = pallas::Base::random(&mut OsRng);
+
+    // This proposal is then hashed, and the hash is signed by the DAO authority:
+    let message =
+        [amount_to_send, *destination_coords.x(), *destination_coords.y(), proposal_blind];
+    let hasher = poseidon::Hash::<_, P128Pow5T3, ConstantLength<4>, 3, 2>::init();
+    let proposal = hasher.hash(message);
+
+    let _signature = dao_authority.secret.sign(&proposal.to_repr());
+
+    // ======
+    // Voting
+    // ======
+
+    // Once the proposal is live, voting can become active.
+    // Users can now vote on the proposal and their votes are weighted by the
+    // balance they commit to their vote.
+    // After the voting process is done, the votes and the blinds are revealed.
+
+    let vote0 = pallas::Base::from(44);
+    let _vote0_blind = pallas::Scalar::random(&mut OsRng);
+
+    let vote1 = pallas::Base::from(14);
+    let _vote1_blind = pallas::Scalar::random(&mut OsRng);
+
+    let vote2 = -pallas::Base::from(39); // This is a NO vote
+    let _vote2_blind = pallas::Scalar::random(&mut OsRng);
+
+    // Now let's consider the voting is done, and the votes are revealed.
+    let votes = vote0 + vote1 + vote2;
+
+    if votes < pallas::Base::from(1) {
+        // In case the sum of the votes is negative, it means that the proposal
+        // has not passed, therefore we don't do anything.
+        return Ok(())
+    }
+
+    // ==================
+    // Proposal execution
+    // ==================
+
+    // The remaining funds in the DAO become the next treasury, so we append
+    // it to the DAO Merkle tree:
+    let new_balance = current_balance - amount_to_send;
+    let new_serial = pallas::Base::random(&mut OsRng);
+    let new_dao_blind = pallas::Base::random(&mut OsRng);
+
+    let message = [spend_contract, new_balance, new_serial, new_dao_blind];
+    let hasher = poseidon::Hash::<_, P128Pow5T3, ConstantLength<4>, 3, 2>::init();
+    let our_new_dao = hasher.hash(message);
+
+    tree.append(&MerkleNode(our_new_dao));
+    tree.witness();
+
+    Ok(())
+}