201 lines
7.4 KiB
Rust
201 lines
7.4 KiB
Rust
use crate::{ApiError, ApiResult};
|
|
use beacon_chain::{BeaconChain, BeaconChainTypes};
|
|
use bls::PublicKey;
|
|
use hex;
|
|
use hyper::{Body, Request};
|
|
use store::{iter::AncestorIter, Store};
|
|
use types::{BeaconState, EthSpec, Hash256, RelativeEpoch, Slot};
|
|
|
|
/// Parse a slot from a `0x` preixed string.
|
|
///
|
|
/// E.g., `"1234"`
|
|
pub fn parse_slot(string: &str) -> Result<Slot, ApiError> {
|
|
string
|
|
.parse::<u64>()
|
|
.map(Slot::from)
|
|
.map_err(|e| ApiError::InvalidQueryParams(format!("Unable to parse slot: {:?}", e)))
|
|
}
|
|
|
|
/// Parse a root from a `0x` preixed string.
|
|
///
|
|
/// E.g., `"0x0000000000000000000000000000000000000000000000000000000000000000"`
|
|
pub fn parse_root(string: &str) -> Result<Hash256, ApiError> {
|
|
const PREFIX: &str = "0x";
|
|
|
|
if string.starts_with(PREFIX) {
|
|
let trimmed = string.trim_start_matches(PREFIX);
|
|
trimmed
|
|
.parse()
|
|
.map_err(|e| ApiError::InvalidQueryParams(format!("Unable to parse root: {:?}", e)))
|
|
} else {
|
|
Err(ApiError::InvalidQueryParams(
|
|
"Root must have a '0x' prefix".to_string(),
|
|
))
|
|
}
|
|
}
|
|
|
|
/// Parse a PublicKey from a `0x` prefixed hex string
|
|
pub fn parse_pubkey(string: &str) -> Result<PublicKey, ApiError> {
|
|
const PREFIX: &str = "0x";
|
|
if string.starts_with(PREFIX) {
|
|
let pubkey_bytes = hex::decode(string.trim_start_matches(PREFIX))
|
|
.map_err(|e| ApiError::InvalidQueryParams(format!("Invalid hex string: {:?}", e)))?;
|
|
let pubkey = PublicKey::from_bytes(pubkey_bytes.as_slice()).map_err(|e| {
|
|
ApiError::InvalidQueryParams(format!("Unable to deserialize public key: {:?}.", e))
|
|
})?;
|
|
return Ok(pubkey);
|
|
} else {
|
|
return Err(ApiError::InvalidQueryParams(
|
|
"Public key must have a '0x' prefix".to_string(),
|
|
));
|
|
}
|
|
}
|
|
|
|
/// Returns the root of the `BeaconBlock` in the canonical chain of `beacon_chain` at the given
|
|
/// `slot`, if possible.
|
|
///
|
|
/// May return a root for a previous slot, in the case of skip slots.
|
|
pub fn block_root_at_slot<T: BeaconChainTypes>(
|
|
beacon_chain: &BeaconChain<T>,
|
|
target: Slot,
|
|
) -> Option<Hash256> {
|
|
beacon_chain
|
|
.rev_iter_block_roots()
|
|
.take_while(|(_root, slot)| *slot >= target)
|
|
.find(|(_root, slot)| *slot == target)
|
|
.map(|(root, _slot)| root)
|
|
}
|
|
|
|
/// Returns a `BeaconState` and it's root in the canonical chain of `beacon_chain` at the given
|
|
/// `slot`, if possible.
|
|
///
|
|
/// Will not return a state if the request slot is in the future. Will return states higher than
|
|
/// the current head by skipping slots.
|
|
pub fn state_at_slot<T: BeaconChainTypes>(
|
|
beacon_chain: &BeaconChain<T>,
|
|
slot: Slot,
|
|
) -> Result<(Hash256, BeaconState<T::EthSpec>), ApiError> {
|
|
let head_state = &beacon_chain.head().beacon_state;
|
|
|
|
if head_state.slot == slot {
|
|
// The request slot is the same as the best block (head) slot.
|
|
|
|
// I'm not sure if this `.clone()` will be optimized out. If not, it seems unnecessary.
|
|
Ok((
|
|
beacon_chain.head().beacon_state_root,
|
|
beacon_chain.head().beacon_state.clone(),
|
|
))
|
|
} else {
|
|
let root = state_root_at_slot(beacon_chain, slot)?;
|
|
|
|
let state: BeaconState<T::EthSpec> = beacon_chain
|
|
.store
|
|
.get(&root)?
|
|
.ok_or_else(|| ApiError::NotFound(format!("Unable to find state at root {}", root)))?;
|
|
|
|
Ok((root, state))
|
|
}
|
|
}
|
|
|
|
/// Returns the root of the `BeaconState` in the canonical chain of `beacon_chain` at the given
|
|
/// `slot`, if possible.
|
|
///
|
|
/// Will not return a state root if the request slot is in the future. Will return state roots
|
|
/// higher than the current head by skipping slots.
|
|
pub fn state_root_at_slot<T: BeaconChainTypes>(
|
|
beacon_chain: &BeaconChain<T>,
|
|
slot: Slot,
|
|
) -> Result<Hash256, ApiError> {
|
|
let head_state = &beacon_chain.head().beacon_state;
|
|
let current_slot = beacon_chain
|
|
.slot()
|
|
.map_err(|_| ApiError::ServerError("Unable to read slot clock".to_string()))?;
|
|
|
|
// There are four scenarios when obtaining a state for a given slot:
|
|
//
|
|
// 1. The request slot is in the future.
|
|
// 2. The request slot is the same as the best block (head) slot.
|
|
// 3. The request slot is prior to the head slot.
|
|
// 4. The request slot is later than the head slot.
|
|
if current_slot < slot {
|
|
// 1. The request slot is in the future. Reject the request.
|
|
//
|
|
// We could actually speculate about future state roots by skipping slots, however that's
|
|
// likely to cause confusion for API users.
|
|
Err(ApiError::InvalidQueryParams(format!(
|
|
"Requested slot {} is past the current slot {}",
|
|
slot, current_slot
|
|
)))
|
|
} else if head_state.slot == slot {
|
|
// 2. The request slot is the same as the best block (head) slot.
|
|
//
|
|
// The head state root is stored in memory, return a reference.
|
|
Ok(beacon_chain.head().beacon_state_root)
|
|
} else if head_state.slot > slot {
|
|
// 3. The request slot is prior to the head slot.
|
|
//
|
|
// Iterate through the state roots on the head state to find the root for that
|
|
// slot. Once the root is found, load it from the database.
|
|
Ok(head_state
|
|
.try_iter_ancestor_roots(beacon_chain.store.clone())
|
|
.ok_or_else(|| ApiError::ServerError("Failed to create roots iterator".to_string()))?
|
|
.find(|(_root, s)| *s == slot)
|
|
.map(|(root, _slot)| root)
|
|
.ok_or_else(|| ApiError::NotFound(format!("Unable to find state at slot {}", slot)))?)
|
|
} else {
|
|
// 4. The request slot is later than the head slot.
|
|
//
|
|
// Use `per_slot_processing` to advance the head state to the present slot,
|
|
// assuming that all slots do not contain a block (i.e., they are skipped slots).
|
|
let mut state = beacon_chain.head().beacon_state.clone();
|
|
let spec = &T::EthSpec::default_spec();
|
|
|
|
for _ in state.slot.as_u64()..slot.as_u64() {
|
|
// Ensure the next epoch state caches are built in case of an epoch transition.
|
|
state.build_committee_cache(RelativeEpoch::Next, spec)?;
|
|
|
|
state_processing::per_slot_processing(&mut state, spec)?;
|
|
}
|
|
|
|
// Note: this is an expensive operation. Once the tree hash cache is implement it may be
|
|
// used here.
|
|
Ok(state.canonical_root())
|
|
}
|
|
}
|
|
|
|
pub fn implementation_pending_response(_req: Request<Body>) -> ApiResult {
|
|
Err(ApiError::NotImplemented(
|
|
"API endpoint has not yet been implemented, but is planned to be soon.".to_owned(),
|
|
))
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn parse_root_works() {
|
|
assert_eq!(
|
|
parse_root("0x0000000000000000000000000000000000000000000000000000000000000000"),
|
|
Ok(Hash256::zero())
|
|
);
|
|
assert_eq!(
|
|
parse_root("0x000000000000000000000000000000000000000000000000000000000000002a"),
|
|
Ok(Hash256::from_low_u64_be(42))
|
|
);
|
|
assert!(
|
|
parse_root("0000000000000000000000000000000000000000000000000000000000000042").is_err()
|
|
);
|
|
assert!(parse_root("0x").is_err());
|
|
assert!(parse_root("0x00").is_err());
|
|
}
|
|
|
|
#[test]
|
|
fn parse_slot_works() {
|
|
assert_eq!(parse_slot("0"), Ok(Slot::new(0)));
|
|
assert_eq!(parse_slot("42"), Ok(Slot::new(42)));
|
|
assert_eq!(parse_slot("10000000"), Ok(Slot::new(10_000_000)));
|
|
assert!(parse_slot("cats").is_err());
|
|
}
|
|
}
|