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Remove old fork_choice crate

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This commit is contained in:
Paul Hauner 2019-06-23 15:05:16 +10:00
parent 77fba0b98e
commit 075c989375
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GPG Key ID: 303E4494BB28068C
25 changed files with 6 additions and 2690 deletions
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1
Cargo.toml
View File

@ -1,6 +1,5 @@
[workspace]
members = [
"eth2/fork_choice",
"eth2/lmd_ghost",
"eth2/operation_pool",
"eth2/state_processing",

1
beacon_node/client/Cargo.toml
View File

@ -10,7 +10,6 @@ network = { path = "../network" }
store = { path = "../store" }
http_server = { path = "../http_server" }
rpc = { path = "../rpc" }
fork_choice = { path = "../../eth2/fork_choice" }
prometheus = "^0.6"
types = { path = "../../eth2/types" }
tree_hash = { path = "../../eth2/utils/tree_hash" }

1
beacon_node/http_server/Cargo.toml
View File

@ -16,7 +16,6 @@ types = { path = "../../eth2/types" }
ssz = { path = "../../eth2/utils/ssz" }
slot_clock = { path = "../../eth2/utils/slot_clock" }
protos = { path = "../../protos" }
fork_choice = { path = "../../eth2/fork_choice" }
grpcio = { version = "0.4", default-features = false, features = ["protobuf-codec"] }
persistent = "^0.4"
protobuf = "2.0.2"

7
beacon_node/network/src/sync/simple_sync.rs
View File

@ -517,7 +517,7 @@ impl<T: BeaconChainTypes> SimpleSync<T> {
self.process_block(peer_id.clone(), block.clone(), network, &"gossip")
{
match outcome {
BlockProcessingOutcome::Processed => SHOULD_FORWARD_GOSSIP_BLOCK,
BlockProcessingOutcome::Processed { .. } => SHOULD_FORWARD_GOSSIP_BLOCK,
BlockProcessingOutcome::ParentUnknown { .. } => {
self.import_queue
.enqueue_full_blocks(vec![block], peer_id.clone());
@ -582,7 +582,7 @@ impl<T: BeaconChainTypes> SimpleSync<T> {
_ => true,
};
if processing_result == Some(BlockProcessingOutcome::Processed) {
if processing_result == Some(BlockProcessingOutcome::Processed { block_root }) {
successful += 1;
}
@ -695,11 +695,12 @@ impl<T: BeaconChainTypes> SimpleSync<T> {
if let Ok(outcome) = processing_result {
match outcome {
BlockProcessingOutcome::Processed => {
BlockProcessingOutcome::Processed { block_root } => {
info!(
self.log, "Imported block from network";
"source" => source,
"slot" => block.slot,
"block_root" => format!("{}", block_root),
"peer" => format!("{:?}", peer_id),
);
}

3
beacon_node/rpc/src/beacon_block.rs
View File

@ -95,12 +95,13 @@ impl<T: BeaconChainTypes> BeaconBlockService for BeaconBlockServiceInstance<T> {
Ok(block) => {
match self.chain.process_block(block.clone()) {
Ok(outcome) => {
if outcome == BlockProcessingOutcome::Processed {
if let BlockProcessingOutcome::Processed { block_root } = outcome {
// Block was successfully processed.
info!(
self.log,
"Valid block from RPC";
"block_slot" => block.slot,
"block_root" => format!("{}", block_root),
);
// TODO: Obtain topics from the network service properly.

25
eth2/fork_choice/Cargo.toml
View File

@ -1,25 +0,0 @@
[package]
name = "fork_choice"
version = "0.1.0"
authors = ["Age Manning <Age@AgeManning.com>"]
edition = "2018"
[[bench]]
name = "benches"
harness = false
[dependencies]
store = { path = "../../beacon_node/store" }
ssz = { path = "../utils/ssz" }
types = { path = "../types" }
log = "0.4.6"
bit-vec = "0.5.0"
[dev-dependencies]
criterion = "0.2"
hex = "0.3.2"
yaml-rust = "0.4.2"
bls = { path = "../utils/bls" }
slot_clock = { path = "../utils/slot_clock" }
beacon_chain = { path = "../../beacon_node/beacon_chain" }
env_logger = "0.6.0"

75
eth2/fork_choice/benches/benches.rs
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@ -1,75 +0,0 @@
use criterion::Criterion;
use criterion::{criterion_group, criterion_main, Benchmark};
use fork_choice::{test_utils::TestingForkChoiceBuilder, ForkChoice, OptimizedLMDGhost};
use std::sync::Arc;
use store::MemoryStore;
use types::{ChainSpec, EthSpec, MainnetEthSpec};
pub type TestedForkChoice<T, U> = OptimizedLMDGhost<T, U>;
pub type TestedEthSpec = MainnetEthSpec;
/// Helper function to setup a builder and spec.
fn setup(
validator_count: usize,
chain_length: usize,
) -> (
TestingForkChoiceBuilder<MemoryStore, TestedEthSpec>,
ChainSpec,
) {
let store = MemoryStore::open();
let builder: TestingForkChoiceBuilder<MemoryStore, TestedEthSpec> =
TestingForkChoiceBuilder::new(validator_count, chain_length, Arc::new(store));
let spec = TestedEthSpec::default_spec();
(builder, spec)
}
/// Benches adding blocks to fork_choice.
fn add_block(c: &mut Criterion) {
let validator_count = 16;
let chain_length = 100;
let (builder, spec) = setup(validator_count, chain_length);
c.bench(
&format!("{}_blocks", chain_length),
Benchmark::new("add_blocks", move |b| {
b.iter(|| {
let mut fc = builder.build::<TestedForkChoice<MemoryStore, TestedEthSpec>>();
for (root, block) in builder.chain.iter().skip(1) {
fc.add_block(block, root, &spec).unwrap();
}
})
})
.sample_size(10),
);
}
/// Benches fork choice head finding.
fn find_head(c: &mut Criterion) {
let validator_count = 16;
let chain_length = 64 * 2;
let (builder, spec) = setup(validator_count, chain_length);
let mut fc = builder.build::<TestedForkChoice<MemoryStore, TestedEthSpec>>();
for (root, block) in builder.chain.iter().skip(1) {
fc.add_block(block, root, &spec).unwrap();
}
let head_root = builder.chain.last().unwrap().0;
for i in 0..validator_count {
fc.add_attestation(i as u64, &head_root, &spec).unwrap();
}
c.bench(
&format!("{}_blocks", chain_length),
Benchmark::new("find_head", move |b| {
b.iter(|| fc.find_head(&builder.genesis_root(), &spec).unwrap())
})
.sample_size(10),
);
}
criterion_group!(benches, add_block, find_head);
criterion_main!(benches);

40
eth2/fork_choice/examples/example.rs
View File

@ -1,40 +0,0 @@
use fork_choice::{test_utils::TestingForkChoiceBuilder, ForkChoice, OptimizedLMDGhost};
use std::sync::Arc;
use store::{MemoryStore, Store};
use types::{BeaconBlock, ChainSpec, EthSpec, Hash256, MainnetEthSpec};
fn main() {
let validator_count = 16;
let chain_length = 100;
let repetitions = 50;
let store = MemoryStore::open();
let builder: TestingForkChoiceBuilder<MemoryStore, MainnetEthSpec> =
TestingForkChoiceBuilder::new(validator_count, chain_length, Arc::new(store));
let fork_choosers: Vec<OptimizedLMDGhost<MemoryStore, MainnetEthSpec>> = (0..repetitions)
.into_iter()
.map(|_| builder.build())
.collect();
let spec = &MainnetEthSpec::default_spec();
println!("Running {} times...", repetitions);
for fc in fork_choosers {
do_thing(fc, &builder.chain, builder.genesis_root(), spec);
}
}
#[inline(never)]
fn do_thing<F: ForkChoice<S>, S: Store>(
mut fc: F,
chain: &[(Hash256, BeaconBlock)],
genesis_root: Hash256,
spec: &ChainSpec,
) {
for (root, block) in chain.iter().skip(1) {
fc.add_block(block, root, spec).unwrap();
}
let _head = fc.find_head(&genesis_root, spec).unwrap();
}

25
eth2/fork_choice/fork_choice/Cargo.toml
View File

@ -1,25 +0,0 @@
[package]
name = "fork_choice"
version = "0.1.0"
authors = ["Age Manning <Age@AgeManning.com>"]
edition = "2018"
[[bench]]
name = "benches"
harness = false
[dependencies]
store = { path = "../../beacon_node/store" }
ssz = { path = "../utils/ssz" }
types = { path = "../types" }
log = "0.4.6"
bit-vec = "0.5.0"
[dev-dependencies]
criterion = "0.2"
hex = "0.3.2"
yaml-rust = "0.4.2"
bls = { path = "../utils/bls" }
slot_clock = { path = "../utils/slot_clock" }
beacon_chain = { path = "../../beacon_node/beacon_chain" }
env_logger = "0.6.0"

75
eth2/fork_choice/fork_choice/benches/benches.rs
View File

@ -1,75 +0,0 @@
use criterion::Criterion;
use criterion::{criterion_group, criterion_main, Benchmark};
use fork_choice::{test_utils::TestingForkChoiceBuilder, ForkChoice, OptimizedLMDGhost};
use std::sync::Arc;
use store::MemoryStore;
use types::{ChainSpec, EthSpec, MainnetEthSpec};
pub type TestedForkChoice<T, U> = OptimizedLMDGhost<T, U>;
pub type TestedEthSpec = MainnetEthSpec;
/// Helper function to setup a builder and spec.
fn setup(
validator_count: usize,
chain_length: usize,
) -> (
TestingForkChoiceBuilder<MemoryStore, TestedEthSpec>,
ChainSpec,
) {
let store = MemoryStore::open();
let builder: TestingForkChoiceBuilder<MemoryStore, TestedEthSpec> =
TestingForkChoiceBuilder::new(validator_count, chain_length, Arc::new(store));
let spec = TestedEthSpec::default_spec();
(builder, spec)
}
/// Benches adding blocks to fork_choice.
fn add_block(c: &mut Criterion) {
let validator_count = 16;
let chain_length = 100;
let (builder, spec) = setup(validator_count, chain_length);
c.bench(
&format!("{}_blocks", chain_length),
Benchmark::new("add_blocks", move |b| {
b.iter(|| {
let mut fc = builder.build::<TestedForkChoice<MemoryStore, TestedEthSpec>>();
for (root, block) in builder.chain.iter().skip(1) {
fc.add_block(block, root, &spec).unwrap();
}
})
})
.sample_size(10),
);
}
/// Benches fork choice head finding.
fn find_head(c: &mut Criterion) {
let validator_count = 16;
let chain_length = 64 * 2;
let (builder, spec) = setup(validator_count, chain_length);
let mut fc = builder.build::<TestedForkChoice<MemoryStore, TestedEthSpec>>();
for (root, block) in builder.chain.iter().skip(1) {
fc.add_block(block, root, &spec).unwrap();
}
let head_root = builder.chain.last().unwrap().0;
for i in 0..validator_count {
fc.add_attestation(i as u64, &head_root, &spec).unwrap();
}
c.bench(
&format!("{}_blocks", chain_length),
Benchmark::new("find_head", move |b| {
b.iter(|| fc.find_head(&builder.genesis_root(), &spec).unwrap())
})
.sample_size(10),
);
}
criterion_group!(benches, add_block, find_head);
criterion_main!(benches);

40
eth2/fork_choice/fork_choice/examples/example.rs
View File

@ -1,40 +0,0 @@
use fork_choice::{test_utils::TestingForkChoiceBuilder, ForkChoice, OptimizedLMDGhost};
use std::sync::Arc;
use store::{MemoryStore, Store};
use types::{BeaconBlock, ChainSpec, EthSpec, Hash256, MainnetEthSpec};
fn main() {
let validator_count = 16;
let chain_length = 100;
let repetitions = 50;
let store = MemoryStore::open();
let builder: TestingForkChoiceBuilder<MemoryStore, MainnetEthSpec> =
TestingForkChoiceBuilder::new(validator_count, chain_length, Arc::new(store));
let fork_choosers: Vec<OptimizedLMDGhost<MemoryStore, MainnetEthSpec>> = (0..repetitions)
.into_iter()
.map(|_| builder.build())
.collect();
let spec = &MainnetEthSpec::default_spec();
println!("Running {} times...", repetitions);
for fc in fork_choosers {
do_thing(fc, &builder.chain, builder.genesis_root(), spec);
}
}
#[inline(never)]
fn do_thing<F: ForkChoice<S>, S: Store>(
mut fc: F,
chain: &[(Hash256, BeaconBlock)],
genesis_root: Hash256,
spec: &ChainSpec,
) {
for (root, block) in chain.iter().skip(1) {
fc.add_block(block, root, spec).unwrap();
}
let _head = fc.find_head(&genesis_root, spec).unwrap();
}

144
eth2/fork_choice/fork_choice/tests/bitwise_lmd_ghost_test_vectors.yaml
View File

@ -1,144 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests for bitwise lmd ghost.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
weights:
- b0: 0
- b1: 0
- b2: 5
- b3: 10
heads:
- id: 'b3'
# bitwise LMD ghost example. bitwise GHOST gives b2
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 4
- b3: 3
heads:
- id: 'b2'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b1'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b6'
weights:
- b0: 0
- b1: 3
- b2: 2
- b3: 1
- b4: 1
- b5: 1
- b6: 2
- b7: 2
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b2'
- id: 'b8'
parent: 'b3'
- id: 'b9'
parent: 'b3'
weights:
- b1: 2
- b2: 1
- b3: 1
- b4: 7
- b5: 5
- b6: 2
- b7: 4
- b8: 4
- b9: 2
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b2'
- id: 'b8'
parent: 'b3'
- id: 'b9'
parent: 'b3'
weights:
- b1: 1
- b2: 1
- b3: 1
- b4: 7
- b5: 5
- b6: 2
- b7: 4
- b8: 4
- b9: 2
heads:
- id: 'b7'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
weights:
- b1: 0
- b2: 0
heads:
- id: 'b1'

65
eth2/fork_choice/fork_choice/tests/lmd_ghost_test_vectors.yaml
View File

@ -1,65 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests for lmd ghost.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
weights:
- b0: 0
- b1: 0
- b2: 5
- b3: 10
heads:
- id: 'b3'
# bitwise LMD ghost example. GHOST gives b1
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 4
- b3: 3
heads:
- id: 'b1'
# equal weights children. Should choose lower hash b2
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 6
- b3: 6
heads:
- id: 'b2'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
weights:
- b1: 0
- b2: 0
heads:
- id: 'b1'

51
eth2/fork_choice/fork_choice/tests/longest_chain_test_vectors.yaml
View File

@ -1,51 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests to verify the longest chain fork-choice rule.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
- id: 'b4'
parent: 'b3'
weights:
- b0: 0
- b1: 0
- b2: 10
- b3: 1
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b2'
- id: 'b4'
parent: 'b3'
- id: 'b5'
parent: 'b0'
- id: 'b6'
parent: 'b5'
- id: 'b7'
parent: 'b6'
- id: 'b8'
parent: 'b7'
- id: 'b9'
parent: 'b8'
weights:
- b0: 5
- b1: 20
- b2: 10
- b3: 10
heads:
- id: 'b9'

231
eth2/fork_choice/fork_choice/tests/tests.rs
View File

@ -1,231 +0,0 @@
#![cfg(not(debug_assertions))]
/// Tests the available fork-choice algorithms
pub use beacon_chain::BeaconChain;
use bls::Signature;
use store::MemoryStore;
use store::Store;
// use env_logger::{Builder, Env};
use fork_choice::{BitwiseLMDGhost, ForkChoice, LongestChain, OptimizedLMDGhost, SlowLMDGhost};
use std::collections::HashMap;
use std::sync::Arc;
use std::{fs::File, io::prelude::*, path::PathBuf};
use types::test_utils::TestingBeaconStateBuilder;
use types::{
BeaconBlock, BeaconBlockBody, Eth1Data, EthSpec, Hash256, Keypair, MainnetEthSpec, Slot,
};
use yaml_rust::yaml;
// Note: We Assume the block Id's are hex-encoded.
#[test]
fn test_optimized_lmd_ghost() {
// set up logging
// Builder::from_env(Env::default().default_filter_or("trace")).init();
test_yaml_vectors::<OptimizedLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_bitwise_lmd_ghost() {
// set up logging
//Builder::from_env(Env::default().default_filter_or("trace")).init();
test_yaml_vectors::<BitwiseLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/bitwise_lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_slow_lmd_ghost() {
test_yaml_vectors::<SlowLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_longest_chain() {
test_yaml_vectors::<LongestChain<MemoryStore>>("tests/longest_chain_test_vectors.yaml", 100);
}
// run a generic test over given YAML test vectors
fn test_yaml_vectors<T: ForkChoice<MemoryStore>>(
yaml_file_path: &str,
emulated_validators: usize, // the number of validators used to give weights.
) {
// load test cases from yaml
let test_cases = load_test_cases_from_yaml(yaml_file_path);
// default vars
let spec = MainnetEthSpec::default_spec();
let zero_hash = Hash256::zero();
let eth1_data = Eth1Data {
deposit_count: 0,
deposit_root: zero_hash.clone(),
block_hash: zero_hash.clone(),
};
let randao_reveal = Signature::empty_signature();
let signature = Signature::empty_signature();
let body = BeaconBlockBody {
eth1_data,
randao_reveal,
graffiti: [0; 32],
proposer_slashings: vec![],
attester_slashings: vec![],
attestations: vec![],
deposits: vec![],
voluntary_exits: vec![],
transfers: vec![],
};
// process the tests
for test_case in test_cases {
// setup a fresh test
let (mut fork_choice, store, state_root) = setup_inital_state::<T>(emulated_validators);
// keep a hashmap of block_id's to block_hashes (random hashes to abstract block_id)
//let mut block_id_map: HashMap<String, Hash256> = HashMap::new();
// keep a list of hash to slot
let mut block_slot: HashMap<Hash256, Slot> = HashMap::new();
// assume the block tree is given to us in order.
let mut genesis_hash = None;
for block in test_case["blocks"].clone().into_vec().unwrap() {
let block_id = block["id"].as_str().unwrap().to_string();
let parent_id = block["parent"].as_str().unwrap().to_string();
// default params for genesis
let block_hash = id_to_hash(&block_id);
let mut slot = spec.genesis_slot;
let previous_block_root = id_to_hash(&parent_id);
// set the slot and parent based off the YAML. Start with genesis;
// if not the genesis, update slot
if parent_id != block_id {
// find parent slot
slot = *(block_slot
.get(&previous_block_root)
.expect("Parent should have a slot number"))
+ 1;
} else {
genesis_hash = Some(block_hash);
}
// update slot mapping
block_slot.insert(block_hash, slot);
// build the BeaconBlock
let beacon_block = BeaconBlock {
slot,
previous_block_root,
state_root: state_root.clone(),
signature: signature.clone(),
body: body.clone(),
};
// Store the block.
store.put(&block_hash, &beacon_block).unwrap();
// run add block for fork choice if not genesis
if parent_id != block_id {
fork_choice
.add_block(&beacon_block, &block_hash, &spec)
.unwrap();
}
}
// add the weights (attestations)
let mut current_validator = 0;
for id_map in test_case["weights"].clone().into_vec().unwrap() {
// get the block id and weights
for (map_id, map_weight) in id_map.as_hash().unwrap().iter() {
let id = map_id.as_str().unwrap();
let block_root = id_to_hash(&id.to_string());
let weight = map_weight.as_i64().unwrap();
// we assume a validator has a value 1 and add an attestation for to achieve the
// correct weight
for _ in 0..weight {
assert!(
current_validator <= emulated_validators,
"Not enough validators to emulate weights"
);
fork_choice
.add_attestation(current_validator as u64, &block_root, &spec)
.unwrap();
current_validator += 1;
}
}
}
// everything is set up, run the fork choice, using genesis as the head
let head = fork_choice
.find_head(&genesis_hash.unwrap(), &spec)
.unwrap();
// compare the result to the expected test
let success = test_case["heads"]
.clone()
.into_vec()
.unwrap()
.iter()
.find(|heads| id_to_hash(&heads["id"].as_str().unwrap().to_string()) == head)
.is_some();
println!("Head found: {}", head);
assert!(success, "Did not find one of the possible heads");
}
}
// loads the test_cases from the supplied yaml file
fn load_test_cases_from_yaml(file_path: &str) -> Vec<yaml_rust::Yaml> {
// load the yaml
let mut file = {
let mut file_path_buf = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
file_path_buf.push(file_path);
File::open(file_path_buf).unwrap()
};
let mut yaml_str = String::new();
file.read_to_string(&mut yaml_str).unwrap();
let docs = yaml::YamlLoader::load_from_str(&yaml_str).unwrap();
let doc = &docs[0];
doc["test_cases"].as_vec().unwrap().clone()
}
fn setup_inital_state<T>(
// fork_choice_algo: &ForkChoiceAlgorithm,
num_validators: usize
) -> (T, Arc<MemoryStore>, Hash256)
where
T: ForkChoice<MemoryStore>,
{
let store = Arc::new(MemoryStore::open());
let fork_choice = ForkChoice::new(store.clone());
let spec = MainnetEthSpec::default_spec();
let mut state_builder: TestingBeaconStateBuilder<MainnetEthSpec> =
TestingBeaconStateBuilder::from_single_keypair(num_validators, &Keypair::random(), &spec);
state_builder.build_caches(&spec).unwrap();
let (state, _keypairs) = state_builder.build();
let state_root = state.canonical_root();
store.put(&state_root, &state).unwrap();
// return initialised vars
(fork_choice, store, state_root)
}
// convert a block_id into a Hash256 -- assume input is hex encoded;
fn id_to_hash(id: &String) -> Hash256 {
let bytes = hex::decode(id).expect("Block ID should be hex");
let len = std::cmp::min(bytes.len(), 32);
let mut fixed_bytes = [0u8; 32];
for (index, byte) in bytes.iter().take(32).enumerate() {
fixed_bytes[32 - len + index] = *byte;
}
Hash256::from(fixed_bytes)
}

476
eth2/fork_choice/src/bitwise_lmd_ghost.rs
View File

@ -1,476 +0,0 @@
//! The optimised bitwise LMD-GHOST fork choice rule.
use crate::{ForkChoice, ForkChoiceError};
use bit_vec::BitVec;
use log::{debug, trace};
use std::collections::HashMap;
use std::marker::PhantomData;
use std::sync::Arc;
use store::Store;
use types::{BeaconBlock, BeaconState, ChainSpec, EthSpec, Hash256, Slot, SlotHeight};
//TODO: Pruning - Children
//TODO: Handle Syncing
// NOTE: This uses u32 to represent difference between block heights. Thus this is only
// applicable for block height differences in the range of a u32.
// This can potentially be parallelized in some parts.
/// Compute the base-2 logarithm of an integer, floored (rounded down)
#[inline]
fn log2_int(x: u64) -> u32 {
if x == 0 {
return 0;
}
63 - x.leading_zeros()
}
fn power_of_2_below(x: u64) -> u64 {
2u64.pow(log2_int(x))
}
/// Stores the necessary data structures to run the optimised bitwise lmd ghost algorithm.
pub struct BitwiseLMDGhost<T, E> {
/// A cache of known ancestors at given heights for a specific block.
//TODO: Consider FnvHashMap
cache: HashMap<CacheKey<u64>, Hash256>,
/// Log lookup table for blocks to their ancestors.
//TODO: Verify we only want/need a size 16 log lookup
ancestors: Vec<HashMap<Hash256, Hash256>>,
/// Stores the children for any given parent.
children: HashMap<Hash256, Vec<Hash256>>,
/// The latest attestation targets as a map of validator index to block hash.
//TODO: Could this be a fixed size vec
latest_attestation_targets: HashMap<u64, Hash256>,
/// Block and state storage.
store: Arc<T>,
max_known_height: SlotHeight,
_phantom: PhantomData<E>,
}
impl<T: Store, E: EthSpec> BitwiseLMDGhost<T, E> {
/// Finds the latest votes weighted by validator balance. Returns a hashmap of block_hash to
/// weighted votes.
pub fn get_latest_votes(
&self,
state_root: &Hash256,
block_slot: Slot,
spec: &ChainSpec,
) -> Result<HashMap<Hash256, u64>, ForkChoiceError> {
// get latest votes
// Note: Votes are weighted by min(balance, MAX_DEPOSIT_AMOUNT) //
// FORK_CHOICE_BALANCE_INCREMENT
// build a hashmap of block_hash to weighted votes
let mut latest_votes: HashMap<Hash256, u64> = HashMap::new();
// gets the current weighted votes
let current_state: BeaconState<E> = self
.store
.get(&state_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconState(*state_root))?;
let active_validator_indices =
current_state.get_active_validator_indices(block_slot.epoch(E::slots_per_epoch()));
for index in active_validator_indices {
let balance = std::cmp::min(current_state.balances[index], spec.max_effective_balance)
/ spec.effective_balance_increment;
if balance > 0 {
if let Some(target) = self.latest_attestation_targets.get(&(index as u64)) {
*latest_votes.entry(*target).or_insert_with(|| 0) += balance;
}
}
}
trace!("Latest votes: {:?}", latest_votes);
Ok(latest_votes)
}
/// Gets the ancestor at a given height `at_height` of a block specified by `block_hash`.
fn get_ancestor(
&mut self,
block_hash: Hash256,
target_height: SlotHeight,
spec: &ChainSpec,
) -> Option<Hash256> {
// return None if we can't get the block from the db.
let block_height = {
let block_slot = self
.store
.get::<BeaconBlock>(&block_hash)
.ok()?
.expect("Should have returned already if None")
.slot;
block_slot.height(spec.genesis_slot)
};
// verify we haven't exceeded the block height
if target_height >= block_height {
if target_height > block_height {
return None;
} else {
return Some(block_hash);
}
}
// check if the result is stored in our cache
let cache_key = CacheKey::new(&block_hash, target_height.as_u64());
if let Some(ancestor) = self.cache.get(&cache_key) {
return Some(*ancestor);
}
// not in the cache recursively search for ancestors using a log-lookup
if let Some(ancestor) = {
let ancestor_lookup = *self.ancestors
[log2_int((block_height - target_height - 1u64).as_u64()) as usize]
.get(&block_hash)
//TODO: Panic if we can't lookup and fork choice fails
.expect("All blocks should be added to the ancestor log lookup table");
self.get_ancestor(ancestor_lookup, target_height, &spec)
} {
// add the result to the cache
self.cache.insert(cache_key, ancestor);
return Some(ancestor);
}
None
}
// looks for an obvious block winner given the latest votes for a specific height
fn get_clear_winner(
&mut self,
latest_votes: &HashMap<Hash256, u64>,
block_height: SlotHeight,
spec: &ChainSpec,
) -> Option<Hash256> {
// map of vote counts for every hash at this height
let mut current_votes: HashMap<Hash256, u64> = HashMap::new();
let mut total_vote_count = 0;
trace!("Clear winner at block height: {}", block_height);
// loop through the latest votes and count all votes
// these have already been weighted by balance
for (hash, votes) in latest_votes.iter() {
if let Some(ancestor) = self.get_ancestor(*hash, block_height, spec) {
let current_vote_value = *current_votes.get(&ancestor).unwrap_or_else(|| &0);
current_votes.insert(ancestor, current_vote_value + *votes);
total_vote_count += votes;
}
}
// Check if there is a clear block winner at this height. If so return it.
for (hash, votes) in current_votes.iter() {
if *votes > total_vote_count / 2 {
// we have a clear winner, return it
return Some(*hash);
}
}
// didn't find a clear winner
None
}
// Finds the best child, splitting children into a binary tree, based on their hashes (Bitwise
// LMD Ghost)
fn choose_best_child(&self, votes: &HashMap<Hash256, u64>) -> Option<Hash256> {
if votes.is_empty() {
return None;
}
let mut bitmask: BitVec = BitVec::new();
// loop through all bits
for bit in 0..=256 {
let mut zero_votes = 0;
let mut one_votes = 0;
let mut single_candidate = (None, false);
trace!("Child vote length: {}", votes.len());
for (candidate, votes) in votes.iter() {
let candidate_bit: BitVec = BitVec::from_bytes(candidate.as_bytes());
// if the bitmasks don't match, exclude candidate
if !bitmask.iter().eq(candidate_bit.iter().take(bit)) {
trace!(
"Child: {} was removed in bit: {} with the bitmask: {:?}",
candidate,
bit,
bitmask
);
continue;
}
if candidate_bit.get(bit) == Some(false) {
zero_votes += votes;
} else {
one_votes += votes;
}
if single_candidate.0.is_none() {
single_candidate.0 = Some(candidate);
single_candidate.1 = true;
} else {
single_candidate.1 = false;
}
}
bitmask.push(one_votes > zero_votes);
if single_candidate.1 {
return Some(*single_candidate.0.expect("Cannot reach this"));
}
}
// should never reach here
None
}
}
impl<T: Store, E: EthSpec> ForkChoice<T> for BitwiseLMDGhost<T, E> {
fn new(store: Arc<T>) -> Self {
BitwiseLMDGhost {
cache: HashMap::new(),
ancestors: vec![HashMap::new(); 16],
latest_attestation_targets: HashMap::new(),
children: HashMap::new(),
max_known_height: SlotHeight::new(0),
store,
_phantom: PhantomData,
}
}
fn add_block(
&mut self,
block: &BeaconBlock,
block_hash: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// get the height of the parent
let parent_height = self
.store
.get::<BeaconBlock>(&block.previous_block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(block.previous_block_root))?
.slot
.height(spec.genesis_slot);
let parent_hash = &block.previous_block_root;
// add the new block to the children of parent
(*self
.children
.entry(block.previous_block_root)
.or_insert_with(|| vec![]))
.push(block_hash.clone());
// build the ancestor data structure
for index in 0..16 {
if parent_height % (1 << index) == 0 {
self.ancestors[index].insert(*block_hash, *parent_hash);
} else {
// TODO: This is unsafe. Will panic if parent_hash doesn't exist. Using it for debugging
let parent_ancestor = self.ancestors[index][parent_hash];
self.ancestors[index].insert(*block_hash, parent_ancestor);
}
}
// update the max height
self.max_known_height = std::cmp::max(self.max_known_height, parent_height + 1);
Ok(())
}
fn add_attestation(
&mut self,
validator_index: u64,
target_block_root: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// simply add the attestation to the latest_attestation_target if the block_height is
// larger
trace!(
"Adding attestation of validator: {:?} for block: {}",
validator_index,
target_block_root
);
let attestation_target = self
.latest_attestation_targets
.entry(validator_index)
.or_insert_with(|| *target_block_root);
// if we already have a value
if attestation_target != target_block_root {
trace!("Old attestation found: {:?}", attestation_target);
// get the height of the target block
let block_height = self
.store
.get::<BeaconBlock>(&target_block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*target_block_root))?
.slot
.height(spec.genesis_slot);
// get the height of the past target block
let past_block_height = self
.store
.get::<BeaconBlock>(&attestation_target)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*attestation_target))?
.slot
.height(spec.genesis_slot);
// update the attestation only if the new target is higher
if past_block_height < block_height {
trace!("Updating old attestation");
*attestation_target = *target_block_root;
}
}
Ok(())
}
/// Perform lmd_ghost on the current chain to find the head.
fn find_head(
&mut self,
justified_block_start: &Hash256,
spec: &ChainSpec,
) -> Result<Hash256, ForkChoiceError> {
debug!(
"Starting optimised fork choice at block: {}",
justified_block_start
);
let block = self
.store
.get::<BeaconBlock>(&justified_block_start)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*justified_block_start))?;
let block_slot = block.slot;
let state_root = block.state_root;
let mut block_height = block_slot.height(spec.genesis_slot);
let mut current_head = *justified_block_start;
let mut latest_votes = self.get_latest_votes(&state_root, block_slot, spec)?;
// remove any votes that don't relate to our current head.
latest_votes
.retain(|hash, _| self.get_ancestor(*hash, block_height, spec) == Some(current_head));
// begin searching for the head
loop {
debug!(
"Iteration for block: {} with vote length: {}",
current_head,
latest_votes.len()
);
// if there are no children, we are done, return the current_head
let children = match self.children.get(&current_head) {
Some(children) => children.clone(),
None => {
debug!("Head found: {}", current_head);
return Ok(current_head);
}
};
// logarithmic lookup blocks to see if there are obvious winners, if so,
// progress to the next iteration.
let mut step =
power_of_2_below(self.max_known_height.saturating_sub(block_height).as_u64()) / 2;
while step > 0 {
trace!("Current Step: {}", step);
if let Some(clear_winner) = self.get_clear_winner(
&latest_votes,
block_height - (block_height % step) + step,
spec,
) {
current_head = clear_winner;
break;
}
step /= 2;
}
if step > 0 {
trace!("Found clear winner: {}", current_head);
}
// if our skip lookup failed and we only have one child, progress to that child
else if children.len() == 1 {
current_head = children[0];
trace!(
"Lookup failed, only one child, proceeding to child: {}",
current_head
);
}
// we need to find the best child path to progress down.
else {
trace!("Searching for best child");
let mut child_votes = HashMap::new();
for (voted_hash, vote) in latest_votes.iter() {
// if the latest votes correspond to a child
if let Some(child) = self.get_ancestor(*voted_hash, block_height + 1, spec) {
// add up the votes for each child
*child_votes.entry(child).or_insert_with(|| 0) += vote;
}
}
// check if we have votes of children, if not select the smallest hash child
if child_votes.is_empty() {
current_head = *children
.iter()
.min_by(|child1, child2| child1.cmp(child2))
.expect("Must be children here");
trace!(
"Children have no votes - smallest hash chosen: {}",
current_head
);
} else {
// given the votes on the children, find the best child
current_head = self
.choose_best_child(&child_votes)
.ok_or(ForkChoiceError::CannotFindBestChild)?;
trace!("Best child found: {}", current_head);
}
}
// didn't find head yet, proceed to next iteration
// update block height
block_height = self
.store
.get::<BeaconBlock>(&current_head)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(current_head))?
.slot
.height(spec.genesis_slot);
// prune the latest votes for votes that are not part of current chosen chain
// more specifically, only keep votes that have head as an ancestor
for hash in latest_votes.keys() {
trace!(
"Ancestor for vote: {} at height: {} is: {:?}",
hash,
block_height,
self.get_ancestor(*hash, block_height, spec)
);
}
latest_votes.retain(|hash, _| {
self.get_ancestor(*hash, block_height, spec) == Some(current_head)
});
}
}
}
/// Type for storing blocks in a memory cache. Key is comprised of block-hash plus the height.
#[derive(PartialEq, Eq, Hash)]
pub struct CacheKey<T> {
block_hash: Hash256,
block_height: T,
}
impl<T> CacheKey<T> {
pub fn new(block_hash: &Hash256, block_height: T) -> Self {
CacheKey {
block_hash: *block_hash,
block_height,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
pub fn test_power_of_2_below() {
assert_eq!(power_of_2_below(4), 4);
assert_eq!(power_of_2_below(5), 4);
assert_eq!(power_of_2_below(7), 4);
assert_eq!(power_of_2_below(24), 16);
assert_eq!(power_of_2_below(32), 32);
assert_eq!(power_of_2_below(33), 32);
assert_eq!(power_of_2_below(63), 32);
}
#[test]
pub fn test_power_of_2_below_large() {
let pow: u64 = 1 << 24;
for x in (pow - 20)..(pow + 20) {
assert!(power_of_2_below(x) <= x, "{}", x);
}
}
}

95
eth2/fork_choice/src/lib.rs
View File

@ -1,95 +0,0 @@
//! This crate stores the various implementations of fork-choice rules that can be used for the
//! beacon blockchain.
//!
//! There are three implementations. One is the naive longest chain rule (primarily for testing
//! purposes). The other two are proposed implementations of the LMD-GHOST fork-choice rule with various forms of optimisation.
//!
//! The current implementations are:
//! - [`longest-chain`]: Simplistic longest-chain fork choice - primarily for testing, **not for
//! production**.
//! - [`slow_lmd_ghost`]: This is a simple and very inefficient implementation given in the ethereum 2.0
//! specifications (https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#get_block_root).
//! - [`bitwise_lmd_ghost`]: This is an optimised version of bitwise LMD-GHOST as proposed
//! by Vitalik. The reference implementation can be found at: https://github.com/ethereum/research/blob/master/ghost/ghost.py
//!
//! [`longest-chain`]: struct.LongestChain.html
//! [`slow_lmd_ghost`]: struct.SlowLmdGhost.html
//! [`bitwise_lmd_ghost`]: struct.OptimisedLmdGhost.html
pub mod bitwise_lmd_ghost;
pub mod longest_chain;
pub mod optimized_lmd_ghost;
pub mod slow_lmd_ghost;
pub mod test_utils;
use std::sync::Arc;
use store::Error as DBError;
use types::{BeaconBlock, ChainSpec, Hash256};
pub use bitwise_lmd_ghost::BitwiseLMDGhost;
pub use longest_chain::LongestChain;
pub use optimized_lmd_ghost::OptimizedLMDGhost;
pub use slow_lmd_ghost::SlowLMDGhost;
/// Defines the interface for Fork Choices. Each Fork choice will define their own data structures
/// which can be built in block processing through the `add_block` and `add_attestation` functions.
/// The main fork choice algorithm is specified in `find_head
pub trait ForkChoice<T>: Send + Sync {
/// Create a new `ForkChoice` which reads from `store`.
fn new(store: Arc<T>) -> Self;
/// Called when a block has been added. Allows generic block-level data structures to be
/// built for a given fork-choice.
fn add_block(
&mut self,
block: &BeaconBlock,
block_hash: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError>;
/// Called when an attestation has been added. Allows generic attestation-level data structures to be built for a given fork choice.
// This can be generalised to a full attestation if required later.
fn add_attestation(
&mut self,
validator_index: u64,
target_block_hash: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError>;
/// The fork-choice algorithm to find the current canonical head of the chain.
// TODO: Remove the justified_start_block parameter and make it internal
fn find_head(
&mut self,
justified_start_block: &Hash256,
spec: &ChainSpec,
) -> Result<Hash256, ForkChoiceError>;
}
/// Possible fork choice errors that can occur.
#[derive(Debug, PartialEq)]
pub enum ForkChoiceError {
MissingBeaconBlock(Hash256),
MissingBeaconState(Hash256),
IncorrectBeaconState(Hash256),
CannotFindBestChild,
ChildrenNotFound,
StorageError(String),
HeadNotFound,
}
impl From<DBError> for ForkChoiceError {
fn from(e: DBError) -> ForkChoiceError {
ForkChoiceError::StorageError(format!("{:?}", e))
}
}
/// Fork choice options that are currently implemented.
#[derive(Debug, Clone)]
pub enum ForkChoiceAlgorithm {
/// Chooses the longest chain becomes the head. Not for production.
LongestChain,
/// A simple and highly inefficient implementation of LMD ghost.
SlowLMDGhost,
/// An optimised version of bitwise LMD-GHOST by Vitalik.
BitwiseLMDGhost,
/// An optimised implementation of LMD ghost.
OptimizedLMDGhost,
}

100
eth2/fork_choice/src/longest_chain.rs
View File

@ -1,100 +0,0 @@
use crate::{ForkChoice, ForkChoiceError};
use std::sync::Arc;
use store::Store;
use types::{BeaconBlock, ChainSpec, Hash256, Slot};
pub struct LongestChain<T> {
/// List of head block hashes
head_block_hashes: Vec<Hash256>,
/// Block storage.
store: Arc<T>,
}
impl<T: Store> ForkChoice<T> for LongestChain<T> {
fn new(store: Arc<T>) -> Self {
LongestChain {
head_block_hashes: Vec::new(),
store,
}
}
fn add_block(
&mut self,
block: &BeaconBlock,
block_hash: &Hash256,
_: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// add the block hash to head_block_hashes removing the parent if it exists
self.head_block_hashes
.retain(|hash| *hash != block.previous_block_root);
self.head_block_hashes.push(*block_hash);
Ok(())
}
fn add_attestation(
&mut self,
_: u64,
_: &Hash256,
_: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// do nothing
Ok(())
}
fn find_head(&mut self, _: &Hash256, _: &ChainSpec) -> Result<Hash256, ForkChoiceError> {
let mut head_blocks: Vec<(usize, BeaconBlock)> = vec![];
/*
* Load all the head_block hashes from the DB as SszBeaconBlocks.
*/
for (index, block_hash) in self.head_block_hashes.iter().enumerate() {
let block: BeaconBlock = self
.store
.get(&block_hash)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*block_hash))?;
head_blocks.push((index, block));
}
/*
* Loop through all the head blocks and find the highest slot.
*/
let highest_slot = head_blocks
.iter()
.fold(Slot::from(0u64), |highest, (_, block)| {
std::cmp::max(block.slot, highest)
});
// if we find no blocks, return Error
if highest_slot == 0 {
return Err(ForkChoiceError::HeadNotFound);
}
/*
* Loop through all the highest blocks and sort them by highest hash.
*
* Ultimately, the index of the head_block hash with the highest slot and highest block
* hash will be the winner.
*/
let head_index: Option<usize> =
head_blocks
.iter()
.fold(None, |smallest_index, (index, block)| {
if block.slot == highest_slot {
if smallest_index.is_none() {
return Some(*index);
}
return Some(std::cmp::min(
*index,
smallest_index.expect("Cannot be None"),
));
}
smallest_index
});
if head_index.is_none() {
return Err(ForkChoiceError::HeadNotFound);
}
Ok(self.head_block_hashes[head_index.unwrap()])
}
}

447
eth2/fork_choice/src/optimized_lmd_ghost.rs
View File

@ -1,447 +0,0 @@
//! The optimised bitwise LMD-GHOST fork choice rule.
use crate::{ForkChoice, ForkChoiceError};
use log::{debug, trace};
use std::cmp::Ordering;
use std::collections::HashMap;
use std::marker::PhantomData;
use std::sync::Arc;
use store::Store;
use types::{BeaconBlock, BeaconState, ChainSpec, EthSpec, Hash256, Slot, SlotHeight};
//TODO: Pruning - Children
//TODO: Handle Syncing
// NOTE: This uses u32 to represent difference between block heights. Thus this is only
// applicable for block height differences in the range of a u32.
// This can potentially be parallelized in some parts.
/// Compute the base-2 logarithm of an integer, floored (rounded down)
#[inline]
fn log2_int(x: u64) -> u32 {
if x == 0 {
return 0;
}
63 - x.leading_zeros()
}
fn power_of_2_below(x: u64) -> u64 {
2u64.pow(log2_int(x))
}
/// Stores the necessary data structures to run the optimised lmd ghost algorithm.
pub struct OptimizedLMDGhost<T, E> {
/// A cache of known ancestors at given heights for a specific block.
//TODO: Consider FnvHashMap
cache: HashMap<CacheKey<u64>, Hash256>,
/// Log lookup table for blocks to their ancestors.
//TODO: Verify we only want/need a size 16 log lookup
ancestors: Vec<HashMap<Hash256, Hash256>>,
/// Stores the children for any given parent.
children: HashMap<Hash256, Vec<Hash256>>,
/// The latest attestation targets as a map of validator index to block hash.
//TODO: Could this be a fixed size vec
latest_attestation_targets: HashMap<u64, Hash256>,
/// Block and state storage.
store: Arc<T>,
max_known_height: SlotHeight,
_phantom: PhantomData<E>,
}
impl<T: Store, E: EthSpec> OptimizedLMDGhost<T, E> {
/// Finds the latest votes weighted by validator balance. Returns a hashmap of block_hash to
/// weighted votes.
pub fn get_latest_votes(
&self,
state_root: &Hash256,
block_slot: Slot,
spec: &ChainSpec,
) -> Result<HashMap<Hash256, u64>, ForkChoiceError> {
// get latest votes
// Note: Votes are weighted by min(balance, MAX_DEPOSIT_AMOUNT) //
// FORK_CHOICE_BALANCE_INCREMENT
// build a hashmap of block_hash to weighted votes
let mut latest_votes: HashMap<Hash256, u64> = HashMap::new();
// gets the current weighted votes
let current_state: BeaconState<E> = self
.store
.get(&state_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconState(*state_root))?;
let active_validator_indices =
current_state.get_active_validator_indices(block_slot.epoch(E::slots_per_epoch()));
for index in active_validator_indices {
let balance = std::cmp::min(current_state.balances[index], spec.max_effective_balance)
/ spec.effective_balance_increment;
if balance > 0 {
if let Some(target) = self.latest_attestation_targets.get(&(index as u64)) {
*latest_votes.entry(*target).or_insert_with(|| 0) += balance;
}
}
}
trace!("Latest votes: {:?}", latest_votes);
Ok(latest_votes)
}
/// Gets the ancestor at a given height `at_height` of a block specified by `block_hash`.
fn get_ancestor(
&mut self,
block_hash: Hash256,
target_height: SlotHeight,
spec: &ChainSpec,
) -> Option<Hash256> {
// return None if we can't get the block from the db.
let block_height = {
let block_slot = self
.store
.get::<BeaconBlock>(&block_hash)
.ok()?
.expect("Should have returned already if None")
.slot;
block_slot.height(spec.genesis_slot)
};
// verify we haven't exceeded the block height
if target_height >= block_height {
if target_height > block_height {
return None;
} else {
return Some(block_hash);
}
}
// check if the result is stored in our cache
let cache_key = CacheKey::new(&block_hash, target_height.as_u64());
if let Some(ancestor) = self.cache.get(&cache_key) {
return Some(*ancestor);
}
// not in the cache recursively search for ancestors using a log-lookup
if let Some(ancestor) = {
let ancestor_lookup = *self.ancestors
[log2_int((block_height - target_height - 1u64).as_u64()) as usize]
.get(&block_hash)
//TODO: Panic if we can't lookup and fork choice fails
.expect("All blocks should be added to the ancestor log lookup table");
self.get_ancestor(ancestor_lookup, target_height, &spec)
} {
// add the result to the cache
self.cache.insert(cache_key, ancestor);
return Some(ancestor);
}
None
}
// looks for an obvious block winner given the latest votes for a specific height
fn get_clear_winner(
&mut self,
latest_votes: &HashMap<Hash256, u64>,
block_height: SlotHeight,
spec: &ChainSpec,
) -> Option<Hash256> {
// map of vote counts for every hash at this height
let mut current_votes: HashMap<Hash256, u64> = HashMap::new();
let mut total_vote_count = 0;
trace!("Clear winner at block height: {}", block_height);
// loop through the latest votes and count all votes
// these have already been weighted by balance
for (hash, votes) in latest_votes.iter() {
if let Some(ancestor) = self.get_ancestor(*hash, block_height, spec) {
let current_vote_value = *current_votes.get(&ancestor).unwrap_or_else(|| &0);
current_votes.insert(ancestor, current_vote_value + *votes);
total_vote_count += votes;
}
}
// Check if there is a clear block winner at this height. If so return it.
for (hash, votes) in current_votes.iter() {
if *votes > total_vote_count / 2 {
// we have a clear winner, return it
return Some(*hash);
}
}
// didn't find a clear winner
None
}
// Finds the best child (one with highest votes)
fn choose_best_child(&self, votes: &HashMap<Hash256, u64>) -> Option<Hash256> {
if votes.is_empty() {
return None;
}
// Iterate through hashmap to get child with maximum votes
let best_child = votes.iter().max_by(|(child1, v1), (child2, v2)| {
let mut result = v1.cmp(v2);
// If votes are equal, choose smaller hash to break ties deterministically
if result == Ordering::Equal {
// Reverse so that max_by chooses smaller hash
result = child1.cmp(child2).reverse();
}
result
});
Some(*best_child.unwrap().0)
}
}
impl<T: Store, E: EthSpec> ForkChoice<T> for OptimizedLMDGhost<T, E> {
fn new(store: Arc<T>) -> Self {
OptimizedLMDGhost {
cache: HashMap::new(),
ancestors: vec![HashMap::new(); 16],
latest_attestation_targets: HashMap::new(),
children: HashMap::new(),
max_known_height: SlotHeight::new(0),
store,
_phantom: PhantomData,
}
}
fn add_block(
&mut self,
block: &BeaconBlock,
block_hash: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// get the height of the parent
let parent_height = self
.store
.get::<BeaconBlock>(&block.previous_block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(block.previous_block_root))?
.slot
.height(spec.genesis_slot);
let parent_hash = &block.previous_block_root;
// add the new block to the children of parent
(*self
.children
.entry(block.previous_block_root)
.or_insert_with(|| vec![]))
.push(block_hash.clone());
// build the ancestor data structure
for index in 0..16 {
if parent_height % (1 << index) == 0 {
self.ancestors[index].insert(*block_hash, *parent_hash);
} else {
// TODO: This is unsafe. Will panic if parent_hash doesn't exist. Using it for debugging
let parent_ancestor = self.ancestors[index][parent_hash];
self.ancestors[index].insert(*block_hash, parent_ancestor);
}
}
// update the max height
self.max_known_height = std::cmp::max(self.max_known_height, parent_height + 1);
Ok(())
}
fn add_attestation(
&mut self,
validator_index: u64,
target_block_root: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// simply add the attestation to the latest_attestation_target if the block_height is
// larger
trace!(
"Adding attestation of validator: {:?} for block: {}",
validator_index,
target_block_root
);
let attestation_target = self
.latest_attestation_targets
.entry(validator_index)
.or_insert_with(|| *target_block_root);
// if we already have a value
if attestation_target != target_block_root {
trace!("Old attestation found: {:?}", attestation_target);
// get the height of the target block
let block_height = self
.store
.get::<BeaconBlock>(&target_block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*target_block_root))?
.slot
.height(spec.genesis_slot);
// get the height of the past target block
let past_block_height = self
.store
.get::<BeaconBlock>(&attestation_target)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*attestation_target))?
.slot
.height(spec.genesis_slot);
// update the attestation only if the new target is higher
if past_block_height < block_height {
trace!("Updating old attestation");
*attestation_target = *target_block_root;
}
}
Ok(())
}
/// Perform lmd_ghost on the current chain to find the head.
fn find_head(
&mut self,
justified_block_start: &Hash256,
spec: &ChainSpec,
) -> Result<Hash256, ForkChoiceError> {
debug!(
"Starting optimised fork choice at block: {}",
justified_block_start
);
let block = self
.store
.get::<BeaconBlock>(&justified_block_start)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*justified_block_start))?;
let block_slot = block.slot;
let state_root = block.state_root;
let mut block_height = block_slot.height(spec.genesis_slot);
let mut current_head = *justified_block_start;
let mut latest_votes = self.get_latest_votes(&state_root, block_slot, spec)?;
// remove any votes that don't relate to our current head.
latest_votes
.retain(|hash, _| self.get_ancestor(*hash, block_height, spec) == Some(current_head));
// begin searching for the head
loop {
debug!(
"Iteration for block: {} with vote length: {}",
current_head,
latest_votes.len()
);
// if there are no children, we are done, return the current_head
let children = match self.children.get(&current_head) {
Some(children) => children.clone(),
None => {
debug!("Head found: {}", current_head);
return Ok(current_head);
}
};
// logarithmic lookup blocks to see if there are obvious winners, if so,
// progress to the next iteration.
let mut step =
power_of_2_below(self.max_known_height.saturating_sub(block_height).as_u64()) / 2;
while step > 0 {
trace!("Current Step: {}", step);
if let Some(clear_winner) = self.get_clear_winner(
&latest_votes,
block_height - (block_height % step) + step,
spec,
) {
current_head = clear_winner;
break;
}
step /= 2;
}
if step > 0 {
trace!("Found clear winner: {}", current_head);
}
// if our skip lookup failed and we only have one child, progress to that child
else if children.len() == 1 {
current_head = children[0];
trace!(
"Lookup failed, only one child, proceeding to child: {}",
current_head
);
}
// we need to find the best child path to progress down.
else {
trace!("Searching for best child");
let mut child_votes = HashMap::new();
for (voted_hash, vote) in latest_votes.iter() {
// if the latest votes correspond to a child
if let Some(child) = self.get_ancestor(*voted_hash, block_height + 1, spec) {
// add up the votes for each child
*child_votes.entry(child).or_insert_with(|| 0) += vote;
}
}
// check if we have votes of children, if not select the smallest hash child
if child_votes.is_empty() {
current_head = *children
.iter()
.min_by(|child1, child2| child1.cmp(child2))
.expect("Must be children here");
trace!(
"Children have no votes - smallest hash chosen: {}",
current_head
);
} else {
// given the votes on the children, find the best child
current_head = self
.choose_best_child(&child_votes)
.ok_or(ForkChoiceError::CannotFindBestChild)?;
trace!("Best child found: {}", current_head);
}
}
// didn't find head yet, proceed to next iteration
// update block height
block_height = self
.store
.get::<BeaconBlock>(&current_head)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(current_head))?
.slot
.height(spec.genesis_slot);
// prune the latest votes for votes that are not part of current chosen chain
// more specifically, only keep votes that have head as an ancestor
for hash in latest_votes.keys() {
trace!(
"Ancestor for vote: {} at height: {} is: {:?}",
hash,
block_height,
self.get_ancestor(*hash, block_height, spec)
);
}
latest_votes.retain(|hash, _| {
self.get_ancestor(*hash, block_height, spec) == Some(current_head)
});
}
}
}
/// Type for storing blocks in a memory cache. Key is comprised of block-hash plus the height.
#[derive(PartialEq, Eq, Hash)]
pub struct CacheKey<T> {
block_hash: Hash256,
block_height: T,
}
impl<T> CacheKey<T> {
pub fn new(block_hash: &Hash256, block_height: T) -> Self {
CacheKey {
block_hash: *block_hash,
block_height,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
pub fn test_power_of_2_below() {
assert_eq!(power_of_2_below(4), 4);
assert_eq!(power_of_2_below(5), 4);
assert_eq!(power_of_2_below(7), 4);
assert_eq!(power_of_2_below(24), 16);
assert_eq!(power_of_2_below(32), 32);
assert_eq!(power_of_2_below(33), 32);
assert_eq!(power_of_2_below(63), 32);
}
#[test]
pub fn test_power_of_2_below_large() {
let pow: u64 = 1 << 24;
for x in (pow - 20)..(pow + 20) {
assert!(power_of_2_below(x) <= x, "{}", x);
}
}
}

212
eth2/fork_choice/src/slow_lmd_ghost.rs
View File

@ -1,212 +0,0 @@
use crate::{ForkChoice, ForkChoiceError};
use log::{debug, trace};
use std::collections::HashMap;
use std::marker::PhantomData;
use std::sync::Arc;
use store::Store;
use types::{BeaconBlock, BeaconState, ChainSpec, EthSpec, Hash256, Slot};
//TODO: Pruning and syncing
pub struct SlowLMDGhost<T, E> {
/// The latest attestation targets as a map of validator index to block hash.
//TODO: Could this be a fixed size vec
latest_attestation_targets: HashMap<u64, Hash256>,
/// Stores the children for any given parent.
children: HashMap<Hash256, Vec<Hash256>>,
/// Block and state storage.
store: Arc<T>,
_phantom: PhantomData<E>,
}
impl<T: Store, E: EthSpec> SlowLMDGhost<T, E> {
/// Finds the latest votes weighted by validator balance. Returns a hashmap of block_hash to
/// weighted votes.
pub fn get_latest_votes(
&self,
state_root: &Hash256,
block_slot: Slot,
spec: &ChainSpec,
) -> Result<HashMap<Hash256, u64>, ForkChoiceError> {
// get latest votes
// Note: Votes are weighted by min(balance, MAX_DEPOSIT_AMOUNT) //
// FORK_CHOICE_BALANCE_INCREMENT
// build a hashmap of block_hash to weighted votes
let mut latest_votes: HashMap<Hash256, u64> = HashMap::new();
// gets the current weighted votes
let current_state: BeaconState<E> = self
.store
.get(state_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconState(*state_root))?;
let active_validator_indices =
current_state.get_active_validator_indices(block_slot.epoch(E::slots_per_epoch()));
for index in active_validator_indices {
let balance = std::cmp::min(current_state.balances[index], spec.max_effective_balance)
/ spec.effective_balance_increment;
if balance > 0 {
if let Some(target) = self.latest_attestation_targets.get(&(index as u64)) {
*latest_votes.entry(*target).or_insert_with(|| 0) += balance;
}
}
}
trace!("Latest votes: {:?}", latest_votes);
Ok(latest_votes)
}
/// Get the total number of votes for some given block root.
///
/// The vote count is incremented each time an attestation target votes for a block root.
fn get_vote_count(
&self,
latest_votes: &HashMap<Hash256, u64>,
block_root: &Hash256,
) -> Result<u64, ForkChoiceError> {
let mut count = 0;
let block_slot = self
.store
.get::<BeaconBlock>(&block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*block_root))?
.slot;
for (vote_hash, votes) in latest_votes.iter() {
let (root_at_slot, _) = self
.store
.get_block_at_preceeding_slot(*vote_hash, block_slot)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*block_root))?;
if root_at_slot == *block_root {
count += votes;
}
}
Ok(count)
}
}
impl<T: Store, E: EthSpec> ForkChoice<T> for SlowLMDGhost<T, E> {
fn new(store: Arc<T>) -> Self {
SlowLMDGhost {
latest_attestation_targets: HashMap::new(),
children: HashMap::new(),
store,
_phantom: PhantomData,
}
}
/// Process when a block is added
fn add_block(
&mut self,
block: &BeaconBlock,
block_hash: &Hash256,
_: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// build the children hashmap
// add the new block to the children of parent
(*self
.children
.entry(block.previous_block_root)
.or_insert_with(|| vec![]))
.push(block_hash.clone());
// complete
Ok(())
}
fn add_attestation(
&mut self,
validator_index: u64,
target_block_root: &Hash256,
spec: &ChainSpec,
) -> Result<(), ForkChoiceError> {
// simply add the attestation to the latest_attestation_target if the block_height is
// larger
trace!(
"Adding attestation of validator: {:?} for block: {}",
validator_index,
target_block_root
);
let attestation_target = self
.latest_attestation_targets
.entry(validator_index)
.or_insert_with(|| *target_block_root);
// if we already have a value
if attestation_target != target_block_root {
trace!("Old attestation found: {:?}", attestation_target);
// get the height of the target block
let block_height = self
.store
.get::<BeaconBlock>(&target_block_root)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*target_block_root))?
.slot
.height(spec.genesis_slot);
// get the height of the past target block
let past_block_height = self
.store
.get::<BeaconBlock>(&attestation_target)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*attestation_target))?
.slot
.height(spec.genesis_slot);
// update the attestation only if the new target is higher
if past_block_height < block_height {
trace!("Updating old attestation");
*attestation_target = *target_block_root;
}
}
Ok(())
}
/// A very inefficient implementation of LMD ghost.
fn find_head(
&mut self,
justified_block_start: &Hash256,
spec: &ChainSpec,
) -> Result<Hash256, ForkChoiceError> {
debug!("Running LMD Ghost Fork-choice rule");
let start = self
.store
.get::<BeaconBlock>(&justified_block_start)?
.ok_or_else(|| ForkChoiceError::MissingBeaconBlock(*justified_block_start))?;
let start_state_root = start.state_root;
let latest_votes = self.get_latest_votes(&start_state_root, start.slot, spec)?;
let mut head_hash = *justified_block_start;
loop {
debug!("Iteration for block: {}", head_hash);
let children = match self.children.get(&head_hash) {
Some(children) => children,
// we have found the head, exit
None => break,
};
// if we only have one child, use it
if children.len() == 1 {
trace!("Single child found.");
head_hash = children[0];
continue;
}
trace!("Children found: {:?}", children);
let mut head_vote_count = 0;
head_hash = children[0];
for child_hash in children {
let vote_count = self.get_vote_count(&latest_votes, &child_hash)?;
trace!("Vote count for child: {} is: {}", child_hash, vote_count);
if vote_count > head_vote_count {
head_hash = *child_hash;
head_vote_count = vote_count;
}
// resolve ties - choose smaller hash
else if vote_count == head_vote_count && *child_hash < head_hash {
head_hash = *child_hash;
}
}
}
Ok(head_hash)
}
}

91
eth2/fork_choice/src/test_utils.rs
View File

@ -1,91 +0,0 @@
use crate::ForkChoice;
use std::marker::PhantomData;
use std::sync::Arc;
use store::Store;
use types::{
test_utils::{SeedableRng, TestRandom, TestingBeaconStateBuilder, XorShiftRng},
BeaconBlock, BeaconState, EthSpec, Hash256, Keypair, MainnetEthSpec,
};
/// Creates a chain of blocks and produces `ForkChoice` instances with pre-filled stores.
pub struct TestingForkChoiceBuilder<S, E> {
store: Arc<S>,
pub chain: Vec<(Hash256, BeaconBlock)>,
_phantom: PhantomData<E>,
}
impl<S: Store, E: EthSpec> TestingForkChoiceBuilder<S, E> {
pub fn new(validator_count: usize, chain_length: usize, store: Arc<S>) -> Self {
let chain =
get_chain_of_blocks::<MainnetEthSpec, S>(chain_length, validator_count, store.clone());
Self {
store,
chain,
_phantom: PhantomData,
}
}
pub fn genesis_root(&self) -> Hash256 {
self.chain[0].0
}
/// Return a new `ForkChoice` instance with a chain stored in it's `Store`.
pub fn build<F: ForkChoice<S>>(&self) -> F {
F::new(self.store.clone())
}
}
fn get_state<T: EthSpec>(validator_count: usize) -> BeaconState<T> {
let spec = T::default_spec();
let builder: TestingBeaconStateBuilder<T> =
TestingBeaconStateBuilder::from_single_keypair(validator_count, &Keypair::random(), &spec);
let (state, _keypairs) = builder.build();
state
}
/// Generates a chain of blocks of length `len`.
///
/// Creates a `BeaconState` for the block and stores it in `Store`, along with the block.
///
/// Returns the chain of blocks.
fn get_chain_of_blocks<T: EthSpec, U: Store>(
len: usize,
validator_count: usize,
store: Arc<U>,
) -> Vec<(Hash256, BeaconBlock)> {
let spec = T::default_spec();
let mut blocks_and_roots: Vec<(Hash256, BeaconBlock)> = vec![];
let mut unique_hashes = (0..).map(Hash256::from);
let mut random_block = BeaconBlock::random_for_test(&mut XorShiftRng::from_seed([42; 16]));
random_block.previous_block_root = Hash256::zero();
let beacon_state = get_state::<T>(validator_count);
for i in 0..len {
let slot = spec.genesis_slot + i as u64;
// Generate and store the state.
let mut state = beacon_state.clone();
state.slot = slot;
let state_root = unique_hashes.next().unwrap();
store.put(&state_root, &state).unwrap();
// Generate the block.
let mut block = random_block.clone();
block.slot = slot;
block.state_root = state_root;
// Chain all the blocks to their parents.
if i > 0 {
block.previous_block_root = blocks_and_roots[i - 1].0;
}
// Store the block.
let block_root = unique_hashes.next().unwrap();
store.put(&block_root, &block).unwrap();
blocks_and_roots.push((block_root, block));
}
blocks_and_roots
}

144
eth2/fork_choice/tests/bitwise_lmd_ghost_test_vectors.yaml
View File

@ -1,144 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests for bitwise lmd ghost.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
weights:
- b0: 0
- b1: 0
- b2: 5
- b3: 10
heads:
- id: 'b3'
# bitwise LMD ghost example. bitwise GHOST gives b2
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 4
- b3: 3
heads:
- id: 'b2'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b1'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b6'
weights:
- b0: 0
- b1: 3
- b2: 2
- b3: 1
- b4: 1
- b5: 1
- b6: 2
- b7: 2
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b2'
- id: 'b8'
parent: 'b3'
- id: 'b9'
parent: 'b3'
weights:
- b1: 2
- b2: 1
- b3: 1
- b4: 7
- b5: 5
- b6: 2
- b7: 4
- b8: 4
- b9: 2
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
- id: 'b4'
parent: 'b1'
- id: 'b5'
parent: 'b1'
- id: 'b6'
parent: 'b2'
- id: 'b7'
parent: 'b2'
- id: 'b8'
parent: 'b3'
- id: 'b9'
parent: 'b3'
weights:
- b1: 1
- b2: 1
- b3: 1
- b4: 7
- b5: 5
- b6: 2
- b7: 4
- b8: 4
- b9: 2
heads:
- id: 'b7'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
weights:
- b1: 0
- b2: 0
heads:
- id: 'b1'

65
eth2/fork_choice/tests/lmd_ghost_test_vectors.yaml
View File

@ -1,65 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests for lmd ghost.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
weights:
- b0: 0
- b1: 0
- b2: 5
- b3: 10
heads:
- id: 'b3'
# bitwise LMD ghost example. GHOST gives b1
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 4
- b3: 3
heads:
- id: 'b1'
# equal weights children. Should choose lower hash b2
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
- id: 'b3'
parent: 'b0'
weights:
- b1: 5
- b2: 6
- b3: 6
heads:
- id: 'b2'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b0'
weights:
- b1: 0
- b2: 0
heads:
- id: 'b1'

51
eth2/fork_choice/tests/longest_chain_test_vectors.yaml
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@ -1,51 +0,0 @@
title: Fork-choice Tests
summary: A collection of abstract fork-choice tests to verify the longest chain fork-choice rule.
test_suite: Fork-Choice
test_cases:
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b1'
- id: 'b4'
parent: 'b3'
weights:
- b0: 0
- b1: 0
- b2: 10
- b3: 1
heads:
- id: 'b4'
- blocks:
- id: 'b0'
parent: 'b0'
- id: 'b1'
parent: 'b0'
- id: 'b2'
parent: 'b1'
- id: 'b3'
parent: 'b2'
- id: 'b4'
parent: 'b3'
- id: 'b5'
parent: 'b0'
- id: 'b6'
parent: 'b5'
- id: 'b7'
parent: 'b6'
- id: 'b8'
parent: 'b7'
- id: 'b9'
parent: 'b8'
weights:
- b0: 5
- b1: 20
- b2: 10
- b3: 10
heads:
- id: 'b9'

231
eth2/fork_choice/tests/tests.rs
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@ -1,231 +0,0 @@
#![cfg(not(debug_assertions))]
/// Tests the available fork-choice algorithms
pub use beacon_chain::BeaconChain;
use bls::Signature;
use store::MemoryStore;
use store::Store;
// use env_logger::{Builder, Env};
use fork_choice::{BitwiseLMDGhost, ForkChoice, LongestChain, OptimizedLMDGhost, SlowLMDGhost};
use std::collections::HashMap;
use std::sync::Arc;
use std::{fs::File, io::prelude::*, path::PathBuf};
use types::test_utils::TestingBeaconStateBuilder;
use types::{
BeaconBlock, BeaconBlockBody, Eth1Data, EthSpec, Hash256, Keypair, MainnetEthSpec, Slot,
};
use yaml_rust::yaml;
// Note: We Assume the block Id's are hex-encoded.
#[test]
fn test_optimized_lmd_ghost() {
// set up logging
// Builder::from_env(Env::default().default_filter_or("trace")).init();
test_yaml_vectors::<OptimizedLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_bitwise_lmd_ghost() {
// set up logging
//Builder::from_env(Env::default().default_filter_or("trace")).init();
test_yaml_vectors::<BitwiseLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/bitwise_lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_slow_lmd_ghost() {
test_yaml_vectors::<SlowLMDGhost<MemoryStore, MainnetEthSpec>>(
"tests/lmd_ghost_test_vectors.yaml",
100,
);
}
#[test]
fn test_longest_chain() {
test_yaml_vectors::<LongestChain<MemoryStore>>("tests/longest_chain_test_vectors.yaml", 100);
}
// run a generic test over given YAML test vectors
fn test_yaml_vectors<T: ForkChoice<MemoryStore>>(
yaml_file_path: &str,
emulated_validators: usize, // the number of validators used to give weights.
) {
// load test cases from yaml
let test_cases = load_test_cases_from_yaml(yaml_file_path);
// default vars
let spec = MainnetEthSpec::default_spec();
let zero_hash = Hash256::zero();
let eth1_data = Eth1Data {
deposit_count: 0,
deposit_root: zero_hash.clone(),
block_hash: zero_hash.clone(),
};
let randao_reveal = Signature::empty_signature();
let signature = Signature::empty_signature();
let body = BeaconBlockBody {
eth1_data,
randao_reveal,
graffiti: [0; 32],
proposer_slashings: vec![],
attester_slashings: vec![],
attestations: vec![],
deposits: vec![],
voluntary_exits: vec![],
transfers: vec![],
};
// process the tests
for test_case in test_cases {
// setup a fresh test
let (mut fork_choice, store, state_root) = setup_inital_state::<T>(emulated_validators);
// keep a hashmap of block_id's to block_hashes (random hashes to abstract block_id)
//let mut block_id_map: HashMap<String, Hash256> = HashMap::new();
// keep a list of hash to slot
let mut block_slot: HashMap<Hash256, Slot> = HashMap::new();
// assume the block tree is given to us in order.
let mut genesis_hash = None;
for block in test_case["blocks"].clone().into_vec().unwrap() {
let block_id = block["id"].as_str().unwrap().to_string();
let parent_id = block["parent"].as_str().unwrap().to_string();
// default params for genesis
let block_hash = id_to_hash(&block_id);
let mut slot = spec.genesis_slot;
let previous_block_root = id_to_hash(&parent_id);
// set the slot and parent based off the YAML. Start with genesis;
// if not the genesis, update slot
if parent_id != block_id {
// find parent slot
slot = *(block_slot
.get(&previous_block_root)
.expect("Parent should have a slot number"))
+ 1;
} else {
genesis_hash = Some(block_hash);
}
// update slot mapping
block_slot.insert(block_hash, slot);
// build the BeaconBlock
let beacon_block = BeaconBlock {
slot,
previous_block_root,
state_root: state_root.clone(),
signature: signature.clone(),
body: body.clone(),
};
// Store the block.
store.put(&block_hash, &beacon_block).unwrap();
// run add block for fork choice if not genesis
if parent_id != block_id {
fork_choice
.add_block(&beacon_block, &block_hash, &spec)
.unwrap();
}
}
// add the weights (attestations)
let mut current_validator = 0;
for id_map in test_case["weights"].clone().into_vec().unwrap() {
// get the block id and weights
for (map_id, map_weight) in id_map.as_hash().unwrap().iter() {
let id = map_id.as_str().unwrap();
let block_root = id_to_hash(&id.to_string());
let weight = map_weight.as_i64().unwrap();
// we assume a validator has a value 1 and add an attestation for to achieve the
// correct weight
for _ in 0..weight {
assert!(
current_validator <= emulated_validators,
"Not enough validators to emulate weights"
);
fork_choice
.add_attestation(current_validator as u64, &block_root, &spec)
.unwrap();
current_validator += 1;
}
}
}
// everything is set up, run the fork choice, using genesis as the head
let head = fork_choice
.find_head(&genesis_hash.unwrap(), &spec)
.unwrap();
// compare the result to the expected test
let success = test_case["heads"]
.clone()
.into_vec()
.unwrap()
.iter()
.find(|heads| id_to_hash(&heads["id"].as_str().unwrap().to_string()) == head)
.is_some();
println!("Head found: {}", head);
assert!(success, "Did not find one of the possible heads");
}
}
// loads the test_cases from the supplied yaml file
fn load_test_cases_from_yaml(file_path: &str) -> Vec<yaml_rust::Yaml> {
// load the yaml
let mut file = {
let mut file_path_buf = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
file_path_buf.push(file_path);
File::open(file_path_buf).unwrap()
};
let mut yaml_str = String::new();
file.read_to_string(&mut yaml_str).unwrap();
let docs = yaml::YamlLoader::load_from_str(&yaml_str).unwrap();
let doc = &docs[0];
doc["test_cases"].as_vec().unwrap().clone()
}
fn setup_inital_state<T>(
// fork_choice_algo: &ForkChoiceAlgorithm,
num_validators: usize,
) -> (T, Arc<MemoryStore>, Hash256)
where
T: ForkChoice<MemoryStore>,
{
let store = Arc::new(MemoryStore::open());
let fork_choice = ForkChoice::new(store.clone());
let spec = MainnetEthSpec::default_spec();
let mut state_builder: TestingBeaconStateBuilder<MainnetEthSpec> =
TestingBeaconStateBuilder::from_single_keypair(num_validators, &Keypair::random(), &spec);
state_builder.build_caches(&spec).unwrap();
let (state, _keypairs) = state_builder.build();
let state_root = state.canonical_root();
store.put(&state_root, &state).unwrap();
// return initialised vars
(fork_choice, store, state_root)
}
// convert a block_id into a Hash256 -- assume input is hex encoded;
fn id_to_hash(id: &String) -> Hash256 {
let bytes = hex::decode(id).expect("Block ID should be hex");
let len = std::cmp::min(bytes.len(), 32);
let mut fixed_bytes = [0u8; 32];
for (index, byte) in bytes.iter().take(32).enumerate() {
fixed_bytes[32 - len + index] = *byte;
}
Hash256::from(fixed_bytes)
}