web3-proxy/web3_proxy/src/app.rs
2022-08-05 19:22:23 +00:00

1050 lines
41 KiB
Rust

use anyhow::Context;
use axum::extract::ws::Message;
use dashmap::mapref::entry::Entry as DashMapEntry;
use dashmap::DashMap;
use ethers::core::utils::keccak256;
use ethers::prelude::{Address, Block, BlockNumber, Bytes, Transaction, TxHash, H256, U64};
use futures::future::Abortable;
use futures::future::{join_all, AbortHandle};
use futures::stream::FuturesUnordered;
use futures::stream::StreamExt;
use futures::Future;
use linkedhashmap::LinkedHashMap;
use migration::{Migrator, MigratorTrait};
use parking_lot::RwLock;
use redis_cell_client::bb8::ErrorSink;
use redis_cell_client::{bb8, RedisCellClient, RedisConnectionManager};
use serde_json::json;
use std::fmt;
use std::mem::size_of_val;
use std::pin::Pin;
use std::str::FromStr;
use std::sync::atomic::{self, AtomicUsize};
use std::sync::Arc;
use std::time::Duration;
use tokio::sync::{broadcast, watch};
use tokio::task::JoinHandle;
use tokio::time::timeout;
use tokio_stream::wrappers::{BroadcastStream, WatchStream};
use tracing::{debug, info, info_span, instrument, trace, warn, Instrument};
use crate::bb8_helpers;
use crate::config::AppConfig;
use crate::connections::Web3Connections;
use crate::firewall::check_firewall_raw;
use crate::jsonrpc::JsonRpcForwardedResponse;
use crate::jsonrpc::JsonRpcForwardedResponseEnum;
use crate::jsonrpc::JsonRpcRequest;
use crate::jsonrpc::JsonRpcRequestEnum;
// TODO: make this customizable?
static APP_USER_AGENT: &str = concat!(
"satoshiandkin/",
env!("CARGO_PKG_NAME"),
"/",
env!("CARGO_PKG_VERSION"),
);
// block hash, method, params
type CacheKey = (H256, String, Option<String>);
// TODO: make something more advanced that keeps track of cache size in bytes
type ResponseLrcCache = RwLock<LinkedHashMap<CacheKey, JsonRpcForwardedResponse>>;
type ActiveRequestsMap = DashMap<CacheKey, watch::Receiver<bool>>;
pub type AnyhowJoinHandle<T> = JoinHandle<anyhow::Result<T>>;
/// flatten a JoinError into an anyhow error
pub async fn flatten_handle<T>(handle: AnyhowJoinHandle<T>) -> anyhow::Result<T> {
match handle.await {
Ok(Ok(result)) => Ok(result),
Ok(Err(err)) => Err(err),
Err(err) => Err(err.into()),
}
}
/// return the first error or okay if everything worked
pub async fn flatten_handles<T>(
mut handles: FuturesUnordered<AnyhowJoinHandle<T>>,
) -> anyhow::Result<()> {
while let Some(x) = handles.next().await {
match x {
Err(e) => return Err(e.into()),
Ok(Err(e)) => return Err(e),
Ok(Ok(_)) => continue,
}
}
Ok(())
}
fn block_num_to_u64(block_num: BlockNumber, latest_block: U64) -> (bool, U64) {
match block_num {
BlockNumber::Earliest => (false, U64::zero()),
BlockNumber::Latest => {
// change "latest" to a number
(true, latest_block)
}
BlockNumber::Number(x) => (false, x),
// TODO: think more about how to handle Pending
BlockNumber::Pending => (false, latest_block),
}
}
fn clean_block_number(
params: &mut serde_json::Value,
block_param_id: usize,
latest_block: U64,
) -> anyhow::Result<U64> {
match params.as_array_mut() {
None => Err(anyhow::anyhow!("params not an array")),
Some(params) => match params.get_mut(block_param_id) {
None => {
if params.len() != block_param_id - 1 {
return Err(anyhow::anyhow!("unexpected params length"));
}
// add the latest block number to the end of the params
params.push(serde_json::to_value(latest_block)?);
Ok(latest_block)
}
Some(x) => {
// convert the json value to a BlockNumber
let block_num: BlockNumber = serde_json::from_value(x.clone())?;
let (modified, block_num) = block_num_to_u64(block_num, latest_block);
// if we changed "latest" to a number, update the params to match
if modified {
*x = serde_json::to_value(block_num)?;
}
Ok(block_num)
}
},
}
}
// TODO: change this to return also return the hash needed
fn block_needed(
method: &str,
params: Option<&mut serde_json::Value>,
head_block: U64,
) -> Option<U64> {
let params = params?;
// TODO: double check these. i think some of the getBlock stuff will never need archive
let block_param_id = match method {
"eth_call" => 1,
"eth_estimateGas" => 1,
"eth_getBalance" => 1,
"eth_getBlockByHash" => {
// TODO: double check that any node can serve this
return None;
}
"eth_getBlockByNumber" => {
// TODO: double check that any node can serve this
return None;
}
"eth_getBlockTransactionCountByHash" => {
// TODO: double check that any node can serve this
return None;
}
"eth_getBlockTransactionCountByNumber" => 0,
"eth_getCode" => 1,
"eth_getLogs" => {
let obj = params[0].as_object_mut().unwrap();
if let Some(x) = obj.get_mut("fromBlock") {
let block_num: BlockNumber = serde_json::from_value(x.clone()).ok()?;
let (modified, block_num) = block_num_to_u64(block_num, head_block);
if modified {
*x = serde_json::to_value(block_num).unwrap();
}
return Some(block_num);
}
if let Some(x) = obj.get_mut("toBlock") {
let block_num: BlockNumber = serde_json::from_value(x.clone()).ok()?;
let (modified, block_num) = block_num_to_u64(block_num, head_block);
if modified {
*x = serde_json::to_value(block_num).unwrap();
}
return Some(block_num);
}
if let Some(x) = obj.get("blockHash") {
// TODO: check a linkedhashmap of recent hashes
// TODO: error if fromBlock or toBlock were set
todo!("handle blockHash {}", x);
}
return None;
}
"eth_getStorageAt" => 2,
"eth_getTransactionByHash" => {
// TODO: not sure how best to look these up
// try full nodes first. retry will use archive
return None;
}
"eth_getTransactionByBlockHashAndIndex" => {
// TODO: check a linkedhashmap of recent hashes
// try full nodes first. retry will use archive
return None;
}
"eth_getTransactionByBlockNumberAndIndex" => 0,
"eth_getTransactionCount" => 1,
"eth_getTransactionReceipt" => {
// TODO: not sure how best to look these up
// try full nodes first. retry will use archive
return None;
}
"eth_getUncleByBlockHashAndIndex" => {
// TODO: check a linkedhashmap of recent hashes
// try full nodes first. retry will use archive
return None;
}
"eth_getUncleByBlockNumberAndIndex" => 0,
"eth_getUncleCountByBlockHash" => {
// TODO: check a linkedhashmap of recent hashes
// try full nodes first. retry will use archive
return None;
}
"eth_getUncleCountByBlockNumber" => 0,
_ => {
// some other command that doesn't take block numbers as an argument
return None;
}
};
match clean_block_number(params, block_param_id, head_block) {
Ok(block) => Some(block),
Err(err) => {
// TODO: seems unlikely that we will get here
// if this is incorrect, it should retry on an archive server
warn!(?err, "could not get block from params");
None
}
}
}
// TODO: think more about TxState. d
#[derive(Clone)]
pub enum TxState {
Pending(Transaction),
Confirmed(Transaction),
Orphaned(Transaction),
}
/// The application
// TODO: this debug impl is way too verbose. make something smaller
// TODO: if Web3ProxyApp is always in an Arc, i think we can avoid having at least some of these internal things in arcs
// TODO: i'm sure this is more arcs than necessary, but spawning futures makes references hard
pub struct Web3ProxyApp {
/// Send requests to the best server available
balanced_rpcs: Arc<Web3Connections>,
/// Send private requests (like eth_sendRawTransaction) to all these servers
private_rpcs: Arc<Web3Connections>,
active_requests: ActiveRequestsMap,
/// bytes available to response_cache (it will be slightly larger than this)
response_cache_max_bytes: AtomicUsize,
response_cache: ResponseLrcCache,
// don't drop this or the sender will stop working
// TODO: broadcast channel instead?
head_block_receiver: watch::Receiver<Arc<Block<TxHash>>>,
pending_tx_sender: broadcast::Sender<TxState>,
pending_transactions: Arc<DashMap<TxHash, TxState>>,
rate_limiter: Option<RedisCellClient>,
db_conn: Option<sea_orm::DatabaseConnection>,
}
impl fmt::Debug for Web3ProxyApp {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
// TODO: the default formatter takes forever to write. this is too quiet though
f.debug_struct("Web3ProxyApp").finish_non_exhaustive()
}
}
impl Web3ProxyApp {
pub fn db_conn(&self) -> &sea_orm::DatabaseConnection {
self.db_conn.as_ref().unwrap()
}
pub fn pending_transactions(&self) -> &DashMap<TxHash, TxState> {
&self.pending_transactions
}
pub fn rate_limiter(&self) -> Option<&RedisCellClient> {
self.rate_limiter.as_ref()
}
// TODO: should we just take the rpc config as the only arg instead?
pub async fn spawn(
app_config: AppConfig,
num_workers: usize,
) -> anyhow::Result<(
Arc<Web3ProxyApp>,
Pin<Box<dyn Future<Output = anyhow::Result<()>>>>,
)> {
// first, we connect to mysql and make sure the latest migrations have run
let db_conn = if let Some(db_url) = app_config.shared.db_url {
let mut db_opt = sea_orm::ConnectOptions::new(db_url);
// TODO: load all these options from the config file
db_opt
.max_connections(100)
.min_connections(num_workers.try_into()?)
.connect_timeout(Duration::from_secs(8))
.idle_timeout(Duration::from_secs(8))
.max_lifetime(Duration::from_secs(60))
.sqlx_logging(true);
// .sqlx_logging_level(log::LevelFilter::Info);
let db_conn = sea_orm::Database::connect(db_opt).await?;
// TODO: if error, roll back
Migrator::up(&db_conn, None).await?;
Some(db_conn)
} else {
info!("no database");
None
};
let balanced_rpcs = app_config.balanced_rpcs.into_values().collect();
let private_rpcs = if let Some(private_rpcs) = app_config.private_rpcs {
private_rpcs.into_values().collect()
} else {
vec![]
};
// TODO: try_join_all instead?
let handles = FuturesUnordered::new();
// make a http shared client
// TODO: can we configure the connection pool? should we?
// TODO: 5 minutes is probably long enough. unlimited is a bad idea if something is wrong with the remote server
let http_client = Some(
reqwest::ClientBuilder::new()
.connect_timeout(Duration::from_secs(5))
.timeout(Duration::from_secs(60))
.user_agent(APP_USER_AGENT)
.build()?,
);
let redis_client_pool = match app_config.shared.redis_url {
Some(redis_url) => {
info!("Connecting to redis on {}", redis_url);
let manager = RedisConnectionManager::new(redis_url)?;
let min_size = num_workers as u32;
let max_size = min_size * 4;
// TODO: min_idle?
// TODO: set max_size based on max expected concurrent connections? set based on num_workers?
let builder = bb8::Pool::builder()
.error_sink(bb8_helpers::RedisErrorSink.boxed_clone())
.min_idle(Some(min_size))
.max_size(max_size);
let pool = builder.build(manager).await?;
Some(pool)
}
None => {
warn!("no redis connection");
None
}
};
let (head_block_sender, head_block_receiver) = watch::channel(Arc::new(Block::default()));
// TODO: will one receiver lagging be okay? how big should this be?
let (pending_tx_sender, pending_tx_receiver) = broadcast::channel(256);
// TODO: use this? it could listen for confirmed transactions and then clear pending_transactions, but the head_block_sender is doing that
drop(pending_tx_receiver);
// TODO: this will grow unbounded!! add some expiration to this. and probably move to redis
let pending_transactions = Arc::new(DashMap::new());
// TODO: don't drop the pending_tx_receiver. instead, read it to mark transactions as "seen". once seen, we won't re-send them
// TODO: once a transaction is "Confirmed" we remove it from the map. this should prevent major memory leaks.
// TODO: we should still have some sort of expiration or maximum size limit for the map
// TODO: attach context to this error
let (balanced_rpcs, balanced_handle) = Web3Connections::spawn(
app_config.shared.chain_id,
balanced_rpcs,
http_client.clone(),
redis_client_pool.clone(),
Some(head_block_sender),
Some(pending_tx_sender.clone()),
pending_transactions.clone(),
)
.await
.context("balanced rpcs")?;
handles.push(balanced_handle);
let private_rpcs = if private_rpcs.is_empty() {
warn!("No private relays configured. Any transactions will be broadcast to the public mempool!");
balanced_rpcs.clone()
} else {
// TODO: attach context to this error
let (private_rpcs, private_handle) = Web3Connections::spawn(
app_config.shared.chain_id,
private_rpcs,
http_client.clone(),
redis_client_pool.clone(),
// subscribing to new heads here won't work well
None,
// TODO: subscribe to pending transactions on the private rpcs?
Some(pending_tx_sender.clone()),
pending_transactions.clone(),
)
.await
.context("private_rpcs")?;
handles.push(private_handle);
private_rpcs
};
// TODO: how much should we allow?
let public_max_burst = app_config.shared.public_rate_limit_per_minute / 3;
let public_rate_limiter = if app_config.shared.public_rate_limit_per_minute == 0 {
None
} else {
redis_client_pool.as_ref().map(|redis_client_pool| {
RedisCellClient::new(
redis_client_pool.clone(),
"ip".to_string(),
public_max_burst,
app_config.shared.public_rate_limit_per_minute,
60,
)
})
};
let app = Self {
balanced_rpcs,
private_rpcs,
active_requests: Default::default(),
response_cache_max_bytes: AtomicUsize::new(app_config.shared.response_cache_max_bytes),
response_cache: Default::default(),
head_block_receiver,
pending_tx_sender,
pending_transactions,
rate_limiter: public_rate_limiter,
db_conn,
};
let app = Arc::new(app);
// create a handle that returns on the first error
// TODO: move this to a helper. i think Web3Connections needs it too
let handle = Box::pin(flatten_handles(handles));
Ok((app, handle))
}
pub async fn eth_subscribe(
self: Arc<Self>,
payload: JsonRpcRequest,
subscription_count: &AtomicUsize,
// TODO: taking a sender for Message instead of the exact json we are planning to send feels wrong, but its easier for now
response_sender: flume::Sender<Message>,
) -> anyhow::Result<(AbortHandle, JsonRpcForwardedResponse)> {
let (subscription_abort_handle, subscription_registration) = AbortHandle::new_pair();
// TODO: this only needs to be unique per connection. we don't need it globably unique
let subscription_id = subscription_count.fetch_add(1, atomic::Ordering::SeqCst);
let subscription_id = U64::from(subscription_id);
// save the id so we can use it in the response
let id = payload.id.clone();
// TODO: calling json! on every request is probably not fast. but we can only match against
// TODO: i think we need a stricter EthSubscribeRequest type that JsonRpcRequest can turn into
match payload.params {
Some(x) if x == json!(["newHeads"]) => {
let head_block_receiver = self.head_block_receiver.clone();
trace!(?subscription_id, "new heads subscription");
tokio::spawn(async move {
let mut head_block_receiver = Abortable::new(
WatchStream::new(head_block_receiver),
subscription_registration,
);
while let Some(new_head) = head_block_receiver.next().await {
// TODO: make a struct for this? using our JsonRpcForwardedResponse won't work because it needs an id
let msg = json!({
"jsonrpc": "2.0",
"method":"eth_subscription",
"params": {
"subscription": subscription_id,
"result": new_head.as_ref(),
},
});
let msg = Message::Text(serde_json::to_string(&msg).unwrap());
if response_sender.send_async(msg).await.is_err() {
// TODO: cancel this subscription earlier? select on head_block_receiver.next() and an abort handle?
break;
};
}
trace!(?subscription_id, "closed new heads subscription");
});
}
Some(x) if x == json!(["newPendingTransactions"]) => {
let pending_tx_receiver = self.pending_tx_sender.subscribe();
let mut pending_tx_receiver = Abortable::new(
BroadcastStream::new(pending_tx_receiver),
subscription_registration,
);
trace!(?subscription_id, "pending transactions subscription");
tokio::spawn(async move {
while let Some(Ok(new_tx_state)) = pending_tx_receiver.next().await {
let new_tx = match new_tx_state {
TxState::Pending(tx) => tx,
TxState::Confirmed(..) => continue,
TxState::Orphaned(tx) => tx,
};
// TODO: make a struct for this? using our JsonRpcForwardedResponse won't work because it needs an id
let msg = json!({
"jsonrpc": "2.0",
"method": "eth_subscription",
"params": {
"subscription": subscription_id,
"result": new_tx.hash,
},
});
let msg = Message::Text(serde_json::to_string(&msg).unwrap());
if response_sender.send_async(msg).await.is_err() {
// TODO: cancel this subscription earlier? select on head_block_receiver.next() and an abort handle?
break;
};
}
trace!(?subscription_id, "closed new heads subscription");
});
}
Some(x) if x == json!(["newPendingFullTransactions"]) => {
// TODO: too much copy/pasta with newPendingTransactions
let pending_tx_receiver = self.pending_tx_sender.subscribe();
let mut pending_tx_receiver = Abortable::new(
BroadcastStream::new(pending_tx_receiver),
subscription_registration,
);
trace!(?subscription_id, "pending transactions subscription");
// TODO: do something with this handle?
tokio::spawn(async move {
while let Some(Ok(new_tx_state)) = pending_tx_receiver.next().await {
let new_tx = match new_tx_state {
TxState::Pending(tx) => tx,
TxState::Confirmed(..) => continue,
TxState::Orphaned(tx) => tx,
};
// TODO: make a struct for this? using our JsonRpcForwardedResponse won't work because it needs an id
let msg = json!({
"jsonrpc": "2.0",
"method": "eth_subscription",
"params": {
"subscription": subscription_id,
// upstream just sends the txid, but we want to send the whole transaction
"result": new_tx,
},
});
let msg = Message::Text(serde_json::to_string(&msg).unwrap());
if response_sender.send_async(msg).await.is_err() {
// TODO: cancel this subscription earlier? select on head_block_receiver.next() and an abort handle?
break;
};
}
trace!(?subscription_id, "closed new heads subscription");
});
}
Some(x) if x == json!(["newPendingRawTransactions"]) => {
// TODO: too much copy/pasta with newPendingTransactions
let pending_tx_receiver = self.pending_tx_sender.subscribe();
let mut pending_tx_receiver = Abortable::new(
BroadcastStream::new(pending_tx_receiver),
subscription_registration,
);
trace!(?subscription_id, "pending transactions subscription");
// TODO: do something with this handle?
tokio::spawn(async move {
while let Some(Ok(new_tx_state)) = pending_tx_receiver.next().await {
let new_tx = match new_tx_state {
TxState::Pending(tx) => tx,
TxState::Confirmed(..) => continue,
TxState::Orphaned(tx) => tx,
};
// TODO: make a struct for this? using our JsonRpcForwardedResponse won't work because it needs an id
let msg = json!({
"jsonrpc": "2.0",
"method": "eth_subscription",
"params": {
"subscription": subscription_id,
// upstream just sends the txid, but we want to send the raw transaction
"result": new_tx.rlp(),
},
});
let msg = Message::Text(serde_json::to_string(&msg).unwrap());
if response_sender.send_async(msg).await.is_err() {
// TODO: cancel this subscription earlier? select on head_block_receiver.next() and an abort handle?
break;
};
}
trace!(?subscription_id, "closed new heads subscription");
});
}
_ => return Err(anyhow::anyhow!("unimplemented")),
}
// TODO: do something with subscription_join_handle?
let response = JsonRpcForwardedResponse::from_value(json!(subscription_id), id);
// TODO: make a `SubscriptonHandle(AbortHandle, JoinHandle)` struct?
Ok((subscription_abort_handle, response))
}
pub fn balanced_rpcs(&self) -> &Web3Connections {
&self.balanced_rpcs
}
pub fn private_rpcs(&self) -> &Web3Connections {
&self.private_rpcs
}
pub fn active_requests(&self) -> &ActiveRequestsMap {
&self.active_requests
}
/// send the request or batch of requests to the approriate RPCs
#[instrument(skip_all)]
pub async fn proxy_web3_rpc(
&self,
request: JsonRpcRequestEnum,
) -> anyhow::Result<JsonRpcForwardedResponseEnum> {
debug!(?request, "proxy_web3_rpc");
// even though we have timeouts on the requests to our backend providers,
// we need a timeout for the incoming request so that retries don't run forever
// TODO: take this as an optional argument. per user max? expiration time instead of duration?
let max_time = Duration::from_secs(120);
// TODO: instrument this with a unique id
let response = match request {
JsonRpcRequestEnum::Single(request) => JsonRpcForwardedResponseEnum::Single(
timeout(max_time, self.proxy_web3_rpc_request(request)).await??,
),
JsonRpcRequestEnum::Batch(requests) => JsonRpcForwardedResponseEnum::Batch(
timeout(max_time, self.proxy_web3_rpc_requests(requests)).await??,
),
};
debug!(?response, "Forwarding response");
Ok(response)
}
// #[instrument(skip_all)]
async fn proxy_web3_rpc_requests(
&self,
requests: Vec<JsonRpcRequest>,
) -> anyhow::Result<Vec<JsonRpcForwardedResponse>> {
// TODO: we should probably change ethers-rs to support this directly
// we cut up the request and send to potentually different servers. this could be a problem.
// if the client needs consistent blocks, they should specify instead of assume batches work on the same
// TODO: is spawning here actually slower?
let num_requests = requests.len();
let responses = join_all(
requests
.into_iter()
.map(|request| self.proxy_web3_rpc_request(request))
.collect::<Vec<_>>(),
)
.await;
// TODO: i'm sure this could be done better with iterators
let mut collected: Vec<JsonRpcForwardedResponse> = Vec::with_capacity(num_requests);
for response in responses {
collected.push(response?);
}
Ok(collected)
}
async fn cached_response(
&self,
// TODO: accept a block hash here also?
min_block_needed: Option<&U64>,
request: &JsonRpcRequest,
) -> anyhow::Result<(
CacheKey,
Result<JsonRpcForwardedResponse, &ResponseLrcCache>,
)> {
// TODO: inspect the request to pick the right cache
// TODO: https://github.com/ethereum/web3.py/blob/master/web3/middleware/cache.py
let request_block_hash = if let Some(min_block_needed) = min_block_needed {
// TODO: maybe this should be on the app and not on balanced_rpcs
self.balanced_rpcs.block_hash(min_block_needed).await?
} else {
// TODO: maybe this should be on the app and not on balanced_rpcs
self.balanced_rpcs.head_block_hash()
};
// TODO: better key? benchmark this
let key = (
request_block_hash,
request.method.clone(),
request.params.clone().map(|x| x.to_string()),
);
if let Some(response) = self.response_cache.read().get(&key) {
// TODO: emit a stat
trace!(?request.method, "cache hit!");
// TODO: can we make references work? maybe put them in an Arc?
return Ok((key, Ok(response.to_owned())));
} else {
// TODO: emit a stat
trace!(?request.method, "cache miss!");
}
// TODO: multiple caches. if head_block_hash is None, have a persistent cache (disk backed?)
let cache = &self.response_cache;
Ok((key, Err(cache)))
}
// #[instrument(skip_all)]
async fn proxy_web3_rpc_request(
&self,
mut request: JsonRpcRequest,
) -> anyhow::Result<JsonRpcForwardedResponse> {
trace!("Received request: {:?}", request);
// TODO: if eth_chainId or net_version, serve those without querying the backend
// TODO: how much should we retry? probably with a timeout and not with a count like this
// TODO: think more about this loop.
// // TODO: add more to this span such as
let span = info_span!("rpc_request");
// let _enter = span.enter(); // DO NOT ENTER! we can't use enter across awaits! (clippy lint soon)
let partial_response: serde_json::Value = match request.method.as_ref() {
// lots of commands are blocked
"admin_addPeer"
| "admin_datadir"
| "admin_startRPC"
| "admin_startWS"
| "admin_stopRPC"
| "admin_stopWS"
| "db_getHex"
| "db_getString"
| "db_putHex"
| "db_putString"
| "debug_chaindbCompact"
| "debug_freezeClient"
| "debug_goTrace"
| "debug_mutexProfile"
| "debug_setBlockProfileRate"
| "debug_setGCPercent"
| "debug_setHead"
| "debug_setMutexProfileFraction"
| "debug_standardTraceBlockToFile"
| "debug_standardTraceBadBlockToFile"
| "debug_startCPUProfile"
| "debug_startGoTrace"
| "debug_stopCPUProfile"
| "debug_stopGoTrace"
| "debug_writeBlockProfile"
| "debug_writeMemProfile"
| "debug_writeMutexProfile"
| "eth_compileLLL"
| "eth_compileSerpent"
| "eth_compileSolidity"
| "eth_getCompilers"
| "eth_sendTransaction"
| "eth_sign"
| "eth_signTransaction"
| "eth_submitHashrate"
| "eth_submitWork"
| "les_addBalance"
| "les_setClientParams"
| "les_setDefaultParams"
| "miner_setExtra"
| "miner_setGasPrice"
| "miner_start"
| "miner_stop"
| "miner_setEtherbase"
| "miner_setGasLimit"
| "personal_importRawKey"
| "personal_listAccounts"
| "personal_lockAccount"
| "personal_newAccount"
| "personal_unlockAccount"
| "personal_sendTransaction"
| "personal_sign"
| "personal_ecRecover"
| "shh_addToGroup"
| "shh_getFilterChanges"
| "shh_getMessages"
| "shh_hasIdentity"
| "shh_newFilter"
| "shh_newGroup"
| "shh_newIdentity"
| "shh_post"
| "shh_uninstallFilter"
| "shh_version" => {
// TODO: proper error code
return Err(anyhow::anyhow!("unsupported"));
}
// TODO: implement these commands
"eth_getFilterChanges"
| "eth_getFilterLogs"
| "eth_newBlockFilter"
| "eth_newFilter"
| "eth_newPendingTransactionFilter"
| "eth_uninstallFilter" => return Err(anyhow::anyhow!("not yet implemented")),
// some commands can use local data or caches
"eth_accounts" => serde_json::Value::Array(vec![]),
"eth_blockNumber" => {
let head_block_number = self.balanced_rpcs.head_block_num();
// TODO: technically, block 0 is okay. i guess we should be using an option
if head_block_number.as_u64() == 0 {
return Err(anyhow::anyhow!("no servers synced"));
}
json!(head_block_number)
}
// TODO: eth_callBundle (https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint#eth_callbundle)
// TODO: eth_cancelPrivateTransaction (https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint#eth_cancelprivatetransaction, but maybe just reject)
// TODO: eth_sendPrivateTransaction (https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint#eth_sendprivatetransaction)
"eth_coinbase" => {
// no need for serving coinbase
// we could return a per-user payment address here, but then we might leak that to dapps
json!(Address::zero())
}
// TODO: eth_estimateGas using anvil?
// TODO: eth_gasPrice that does awesome magic to predict the future
"eth_hashrate" => {
json!(U64::zero())
}
"eth_mining" => {
json!(false)
}
// TODO: eth_sendBundle (flashbots command)
// broadcast transactions to all private rpcs at once
"eth_sendRawTransaction" => match &request.params {
Some(serde_json::Value::Array(params)) => {
// parsing params like this is gross. make struct and use serde to do all these checks and error handling
if params.len() != 1 || !params[0].is_string() {
return Err(anyhow::anyhow!("invalid request"));
}
let raw_tx = Bytes::from_str(params[0].as_str().unwrap())?;
if check_firewall_raw(&raw_tx).await? {
return self
.private_rpcs
.try_send_all_upstream_servers(request, None)
.instrument(span)
.await;
} else {
return Err(anyhow::anyhow!("transaction blocked by firewall"));
}
}
_ => return Err(anyhow::anyhow!("invalid request")),
},
"eth_syncing" => {
// TODO: return a real response if all backends are syncing or if no servers in sync
json!(false)
}
"net_listening" => {
// TODO: only if there are some backends on balanced_rpcs?
json!(true)
}
"net_peerCount" => self.balanced_rpcs.num_synced_rpcs().into(),
"web3_clientVersion" => serde_json::Value::String(APP_USER_AGENT.to_string()),
"web3_sha3" => {
// returns Keccak-256 (not the standardized SHA3-256) of the given data.
match &request.params {
Some(serde_json::Value::Array(params)) => {
if params.len() != 1 || !params[0].is_string() {
return Err(anyhow::anyhow!("invalid request"));
}
let param = Bytes::from_str(params[0].as_str().unwrap())?;
let hash = H256::from(keccak256(param));
json!(hash)
}
_ => return Err(anyhow::anyhow!("invalid request")),
}
}
// TODO: web3_sha3?
// anything else gets sent to backend rpcs and cached
method => {
let head_block_number = self.balanced_rpcs.head_block_num();
// we do this check before checking caches because it might modify the request params
// TODO: add a stat for archive vs full since they should probably cost different
let min_block_needed =
block_needed(method, request.params.as_mut(), head_block_number);
let min_block_needed = min_block_needed.as_ref();
trace!(?min_block_needed, ?method);
let (cache_key, cache_result) =
self.cached_response(min_block_needed, &request).await?;
let response_cache = match cache_result {
Ok(response) => {
let _ = self.active_requests.remove(&cache_key);
// TODO: if the response is cached, should it count less against the account's costs?
return Ok(response);
}
Err(response_cache) => response_cache,
};
// check if this request is already in flight
// TODO: move this logic into an IncomingRequestHandler (ActiveRequestHandler has an rpc, but this won't)
let (incoming_tx, incoming_rx) = watch::channel(true);
let mut other_incoming_rx = None;
match self.active_requests.entry(cache_key.clone()) {
DashMapEntry::Occupied(entry) => {
other_incoming_rx = Some(entry.get().clone());
}
DashMapEntry::Vacant(entry) => {
entry.insert(incoming_rx);
}
}
if let Some(mut other_incoming_rx) = other_incoming_rx {
// wait for the other request to finish. it might have finished successfully or with an error
trace!("{:?} waiting on in-flight request", request);
let _ = other_incoming_rx.changed().await;
// now that we've waited, lets check the cache again
if let Some(cached) = response_cache.read().get(&cache_key) {
let _ = self.active_requests.remove(&cache_key);
let _ = incoming_tx.send(false);
// TODO: emit a stat
trace!(
"{:?} cache hit after waiting for in-flight request!",
request
);
return Ok(cached.to_owned());
} else {
// TODO: emit a stat
trace!(
"{:?} cache miss after waiting for in-flight request!",
request
);
}
}
let response = match method {
"eth_getTransactionByHash" | "eth_getTransactionReceipt" => {
// TODO: try_send_all serially with retries instead of parallel
self.private_rpcs
.try_send_all_upstream_servers(request, min_block_needed)
.await?
}
_ => {
// TODO: retries?
self.balanced_rpcs
.try_send_best_upstream_server(request, min_block_needed)
.await?
}
};
// TODO: move this caching outside this match and cache some of the other responses?
// TODO: cache the warp::reply to save us serializing every time?
{
let mut response_cache = response_cache.write();
let response_cache_max_bytes = self
.response_cache_max_bytes
.load(atomic::Ordering::Acquire);
// TODO: this might be too naive. not sure how much overhead the object has
let new_size = size_of_val(&cache_key) + size_of_val(&response);
// no item is allowed to take more than 1% of the cache
// TODO: get this from config?
if new_size < response_cache_max_bytes / 100 {
// TODO: this probably has wildly variable timings
while size_of_val(&response_cache) + new_size >= response_cache_max_bytes {
// TODO: this isn't an LRU. it's a "least recently created". does that have a fancy name? should we make it an lru? these caches only live for one block
response_cache.pop_front();
}
response_cache.insert(cache_key.clone(), response.clone());
} else {
// TODO: emit a stat instead?
warn!(?new_size, "value too large for caching");
}
}
let _ = self.active_requests.remove(&cache_key);
let _ = incoming_tx.send(false);
return Ok(response);
}
};
let response = JsonRpcForwardedResponse::from_value(partial_response, request.id);
Ok(response)
}
}