From 1097c8089b5baa6da8280cb722098d90228e9fcd Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Fri, 1 Mar 2019 16:54:59 +1100
Subject: [PATCH] Add naive deposit-handling to BeaconChain

---
 beacon_node/beacon_chain/src/beacon_chain.rs  | 39 +++++++++++++++++--
 .../state_processing/src/block_processable.rs | 28 ++++++++++---
 2 files changed, 58 insertions(+), 9 deletions(-)

diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 1065f661d6..80cc793051 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -15,9 +15,7 @@ use state_processing::{
 use std::sync::Arc;
 use types::{
     readers::{BeaconBlockReader, BeaconStateReader},
-    AttestationData, BeaconBlock, BeaconBlockBody, BeaconState, BeaconStateError, ChainSpec,
-    Crosslink, Deposit, Epoch, Eth1Data, FreeAttestation, Hash256, PublicKey, RelativeEpoch,
-    Signature, Slot,
+    *,
 };
 
 #[derive(Debug, PartialEq)]
@@ -66,6 +64,7 @@ pub struct BeaconChain<T: ClientDB + Sized, U: SlotClock, F: ForkChoice> {
     pub state_store: Arc<BeaconStateStore<T>>,
     pub slot_clock: U,
     pub attestation_aggregator: RwLock<AttestationAggregator>,
+    pub deposits_for_inclusion: RwLock<Vec<Deposit>>,
     canonical_head: RwLock<CheckPoint>,
     finalized_head: RwLock<CheckPoint>,
     pub state: RwLock<BeaconState>,
@@ -132,6 +131,7 @@ where
             state_store,
             slot_clock,
             attestation_aggregator,
+            deposits_for_inclusion: RwLock::new(vec![]),
             state: RwLock::new(genesis_state),
             finalized_head,
             canonical_head,
@@ -364,6 +364,34 @@ where
         Ok(aggregation_outcome)
     }
 
+    pub fn receive_deposit_for_inclusion(&self, deposit: Deposit) {
+        // TODO: deposits are not check for validity; check them.
+        self.deposits_for_inclusion.write().push(deposit);
+    }
+
+    pub fn get_deposits_for_block(&self) -> Vec<Deposit> {
+        // TODO: deposits are indiscriminately included; check them for validity.
+        self.deposits_for_inclusion.read().clone()
+    }
+
+    pub fn mark_deposits_as_included(&self, included_deposits: &[Deposit]) {
+        // TODO: method does not take forks into account; consider this.
+        let mut indices_to_delete = vec![];
+
+        for included in included_deposits {
+            for (i, for_inclusion) in self.deposits_for_inclusion.read().iter().enumerate() {
+                if included == for_inclusion {
+                    indices_to_delete.push(i);
+                }
+            }
+        }
+
+        let deposits_for_inclusion = &mut self.deposits_for_inclusion.write();
+        for i in indices_to_delete {
+            deposits_for_inclusion.remove(i);
+        }
+    }
+
     /// Dumps the entire canonical chain, from the head to genesis to a vector for analysis.
     ///
     /// This could be a very expensive operation and should only be done in testing/analysis
@@ -488,6 +516,9 @@ where
         self.block_store.put(&block_root, &ssz_encode(&block)[..])?;
         self.state_store.put(&state_root, &ssz_encode(&state)[..])?;
 
+        // Remove any included deposits from the for-inclusion queue
+        self.mark_deposits_as_included(&block.body.deposits[..]);
+
         // run the fork_choice add_block logic
         self.fork_choice
             .write()
@@ -544,7 +575,7 @@ where
                 proposer_slashings: vec![],
                 attester_slashings: vec![],
                 attestations,
-                deposits: vec![],
+                deposits: self.get_deposits_for_block(),
                 exits: vec![],
             },
         };
diff --git a/eth2/state_processing/src/block_processable.rs b/eth2/state_processing/src/block_processable.rs
index effaa65079..aab87c3ad2 100644
--- a/eth2/state_processing/src/block_processable.rs
+++ b/eth2/state_processing/src/block_processable.rs
@@ -3,10 +3,7 @@ use hashing::hash;
 use int_to_bytes::int_to_bytes32;
 use log::{debug, trace};
 use ssz::{ssz_encode, TreeHash};
-use types::{
-    AggregatePublicKey, Attestation, BeaconBlock, BeaconState, BeaconStateError, ChainSpec,
-    Crosslink, Epoch, Exit, Fork, Hash256, PendingAttestation, PublicKey, RelativeEpoch, Signature,
-};
+use types::*;
 
 // TODO: define elsehwere.
 const DOMAIN_PROPOSAL: u64 = 2;
@@ -35,6 +32,7 @@ pub enum Error {
     InvalidAttestation(AttestationValidationError),
     NoBlockRoot,
     MaxDepositsExceeded,
+    BadDeposit,
     MaxExitsExceeded,
     BadExit,
     BadCustodyReseeds,
@@ -242,7 +240,27 @@ fn per_block_processing_signature_optional(
         Error::MaxDepositsExceeded
     );
 
-    // TODO: process deposits.
+    // TODO: verify deposit merkle branches.
+    for deposit in &block.body.deposits {
+        debug!(
+            "Processing deposit for pubkey {:?}",
+            deposit.deposit_data.deposit_input.pubkey
+        );
+        state
+            .process_deposit(
+                deposit.deposit_data.deposit_input.pubkey.clone(),
+                deposit.deposit_data.amount,
+                deposit
+                    .deposit_data
+                    .deposit_input
+                    .proof_of_possession
+                    .clone(),
+                deposit.deposit_data.deposit_input.withdrawal_credentials,
+                None,
+                spec,
+            )
+            .map_err(|_| Error::BadDeposit)?;
+    }
 
     /*
      * Exits