web3-proxy/web3_proxy/src/rpcs/connections.rs
2023-01-19 17:57:36 -08:00

1396 lines
52 KiB
Rust

///! Load balanced communication with a group of web3 providers
use super::blockchain::{ArcBlock, BlockHashesCache};
use super::connection::Web3Connection;
use super::request::{
OpenRequestHandle, OpenRequestHandleMetrics, OpenRequestResult, RequestRevertHandler,
};
use super::synced_connections::ConsensusConnections;
use crate::app::{flatten_handle, AnyhowJoinHandle};
use crate::config::{BlockAndRpc, TxHashAndRpc, Web3ConnectionConfig};
use crate::frontend::authorization::{Authorization, RequestMetadata};
use crate::frontend::rpc_proxy_ws::ProxyMode;
use crate::jsonrpc::{JsonRpcForwardedResponse, JsonRpcRequest};
use crate::rpcs::transactions::TxStatus;
use arc_swap::ArcSwap;
use counter::Counter;
use derive_more::From;
use ethers::prelude::{ProviderError, TxHash, H256, U64};
use futures::future::{join_all, try_join_all};
use futures::stream::FuturesUnordered;
use futures::StreamExt;
use hashbrown::HashMap;
use log::{debug, error, info, trace, warn, Level};
use migration::sea_orm::DatabaseConnection;
use moka::future::{Cache, ConcurrentCacheExt};
use serde::ser::{SerializeStruct, Serializer};
use serde::Serialize;
use serde_json::json;
use serde_json::value::RawValue;
use std::collections::BTreeMap;
use std::fmt;
use std::sync::atomic::Ordering;
use std::sync::Arc;
use thread_fast_rng::rand::seq::SliceRandom;
use tokio::sync::{broadcast, watch};
use tokio::task;
use tokio::time::{interval, sleep, sleep_until, Duration, Instant, MissedTickBehavior};
/// A collection of web3 connections. Sends requests either the current best server or all servers.
#[derive(From)]
pub struct Web3Connections {
pub(crate) conns: HashMap<String, Arc<Web3Connection>>,
/// any requests will be forwarded to one (or more) of these connections
pub(super) synced_connections: ArcSwap<ConsensusConnections>,
pub(super) pending_transactions:
Cache<TxHash, TxStatus, hashbrown::hash_map::DefaultHashBuilder>,
/// TODO: this map is going to grow forever unless we do some sort of pruning. maybe store pruned in redis?
/// all blocks, including orphans
pub(super) block_hashes: BlockHashesCache,
/// blocks on the heaviest chain
pub(super) block_numbers: Cache<U64, H256, hashbrown::hash_map::DefaultHashBuilder>,
pub(super) min_head_rpcs: usize,
pub(super) min_sum_soft_limit: u32,
}
impl Web3Connections {
/// Spawn durable connections to multiple Web3 providers.
#[allow(clippy::too_many_arguments)]
pub async fn spawn(
chain_id: u64,
db_conn: Option<DatabaseConnection>,
server_configs: HashMap<String, Web3ConnectionConfig>,
http_client: Option<reqwest::Client>,
redis_pool: Option<redis_rate_limiter::RedisPool>,
block_map: BlockHashesCache,
head_block_sender: Option<watch::Sender<ArcBlock>>,
min_sum_soft_limit: u32,
min_head_rpcs: usize,
pending_tx_sender: Option<broadcast::Sender<TxStatus>>,
pending_transactions: Cache<TxHash, TxStatus, hashbrown::hash_map::DefaultHashBuilder>,
open_request_handle_metrics: Arc<OpenRequestHandleMetrics>,
) -> anyhow::Result<(Arc<Self>, AnyhowJoinHandle<()>)> {
let (pending_tx_id_sender, pending_tx_id_receiver) = flume::unbounded();
let (block_sender, block_receiver) = flume::unbounded::<BlockAndRpc>();
// TODO: query the rpc to get the actual expected block time, or get from config?
let expected_block_time_ms = match chain_id {
// ethereum
1 => 12_000,
// polygon
137 => 2_000,
// fantom
250 => 1_000,
// arbitrum
42161 => 500,
// anything else
_ => {
warn!("unexpected chain_id. polling every {} seconds", 10);
10_000
}
};
let http_interval_sender = if http_client.is_some() {
let (sender, receiver) = broadcast::channel(1);
drop(receiver);
// TODO: what interval? follow a websocket also? maybe by watching synced connections with a timeout. will need debounce
let mut interval = interval(Duration::from_millis(expected_block_time_ms));
interval.set_missed_tick_behavior(MissedTickBehavior::Delay);
let sender = Arc::new(sender);
let f = {
let sender = sender.clone();
async move {
loop {
// TODO: every time a head_block arrives (with a small delay for known slow servers), or on the interval.
interval.tick().await;
// // trace!("http interval ready");
// errors are okay. they mean that all receivers have been dropped
let _ = sender.send(());
}
}
};
// TODO: do something with this handle?
tokio::spawn(f);
Some(sender)
} else {
None
};
// turn configs into connections (in parallel)
// TODO: move this into a helper function. then we can use it when configs change (will need a remove function too)
let spawn_handles: Vec<_> = server_configs
.into_iter()
.filter_map(|(server_name, server_config)| {
if server_config.disabled {
return None;
}
let db_conn = db_conn.clone();
let http_client = http_client.clone();
let redis_pool = redis_pool.clone();
let http_interval_sender = http_interval_sender.clone();
let block_sender = if head_block_sender.is_some() {
Some(block_sender.clone())
} else {
None
};
let pending_tx_id_sender = Some(pending_tx_id_sender.clone());
let block_map = block_map.clone();
let open_request_handle_metrics = open_request_handle_metrics.clone();
let handle = tokio::spawn(async move {
server_config
.spawn(
server_name,
db_conn,
redis_pool,
chain_id,
http_client,
http_interval_sender,
block_map,
block_sender,
pending_tx_id_sender,
open_request_handle_metrics,
)
.await
});
Some(handle)
})
.collect();
// map of connection names to their connection
let mut connections = HashMap::new();
let mut handles = vec![];
// TODO: do we need to join this?
for x in join_all(spawn_handles).await {
// TODO: how should we handle errors here? one rpc being down shouldn't cause the program to exit
match x {
Ok(Ok((connection, handle))) => {
connections.insert(connection.name.clone(), connection);
handles.push(handle);
}
Ok(Err(err)) => {
// if we got an error here, it is not retryable
// TODO: include context about which connection failed
error!("Unable to create connection. err={:?}", err);
}
Err(err) => {
return Err(err.into());
}
}
}
let synced_connections = ConsensusConnections::default();
// TODO: max_capacity and time_to_idle from config
// all block hashes are the same size, so no need for weigher
let block_hashes = Cache::builder()
.time_to_idle(Duration::from_secs(600))
.max_capacity(10_000)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default());
// all block numbers are the same size, so no need for weigher
let block_numbers = Cache::builder()
.time_to_idle(Duration::from_secs(600))
.max_capacity(10_000)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default());
let connections = Arc::new(Self {
conns: connections,
synced_connections: ArcSwap::new(Arc::new(synced_connections)),
pending_transactions,
block_hashes,
block_numbers,
min_sum_soft_limit,
min_head_rpcs,
});
let authorization = Arc::new(Authorization::internal(db_conn.clone())?);
let handle = {
let connections = connections.clone();
tokio::spawn(async move {
// TODO: try_join_all with the other handles here
connections
.subscribe(
authorization,
pending_tx_id_receiver,
block_receiver,
head_block_sender,
pending_tx_sender,
)
.await
})
};
Ok((connections, handle))
}
pub fn get(&self, conn_name: &str) -> Option<&Arc<Web3Connection>> {
self.conns.get(conn_name)
}
/// subscribe to blocks and transactions from all the backend rpcs.
/// blocks are processed by all the `Web3Connection`s and then sent to the `block_receiver`
/// transaction ids from all the `Web3Connection`s are deduplicated and forwarded to `pending_tx_sender`
async fn subscribe(
self: Arc<Self>,
authorization: Arc<Authorization>,
pending_tx_id_receiver: flume::Receiver<TxHashAndRpc>,
block_receiver: flume::Receiver<BlockAndRpc>,
head_block_sender: Option<watch::Sender<ArcBlock>>,
pending_tx_sender: Option<broadcast::Sender<TxStatus>>,
) -> anyhow::Result<()> {
let mut futures = vec![];
// setup the transaction funnel
// it skips any duplicates (unless they are being orphaned)
// fetches new transactions from the notifying rpc
// forwards new transacitons to pending_tx_receipt_sender
if let Some(pending_tx_sender) = pending_tx_sender.clone() {
let clone = self.clone();
let authorization = authorization.clone();
let handle = task::spawn(async move {
// TODO: set up this future the same as the block funnel
while let Ok((pending_tx_id, rpc)) = pending_tx_id_receiver.recv_async().await {
let f = clone.clone().process_incoming_tx_id(
authorization.clone(),
rpc,
pending_tx_id,
pending_tx_sender.clone(),
);
tokio::spawn(f);
}
Ok(())
});
futures.push(flatten_handle(handle));
}
// setup the block funnel
if let Some(head_block_sender) = head_block_sender {
let connections = Arc::clone(&self);
let pending_tx_sender = pending_tx_sender.clone();
let handle = task::Builder::default()
.name("process_incoming_blocks")
.spawn(async move {
connections
.process_incoming_blocks(
&authorization,
block_receiver,
head_block_sender,
pending_tx_sender,
)
.await
})?;
futures.push(flatten_handle(handle));
}
if futures.is_empty() {
// no transaction or block subscriptions.
let handle = task::Builder::default().name("noop").spawn(async move {
loop {
sleep(Duration::from_secs(600)).await;
// TODO: "every interval, check that the provider is still connected"
}
})?;
futures.push(flatten_handle(handle));
}
if let Err(e) = try_join_all(futures).await {
error!("subscriptions over: {:?}", self);
return Err(e);
}
info!("subscriptions over: {:?}", self);
Ok(())
}
/// Send the same request to all the handles. Returning the most common success or most common error.
/// TODO: option to return the fastest response and handles for all the others instead?
pub async fn try_send_parallel_requests(
&self,
active_request_handles: Vec<OpenRequestHandle>,
id: Box<RawValue>,
method: &str,
params: Option<&serde_json::Value>,
error_level: Level,
// TODO: remove this box once i figure out how to do the options
) -> anyhow::Result<JsonRpcForwardedResponse> {
// TODO: if only 1 active_request_handles, do self.try_send_request?
let responses = active_request_handles
.into_iter()
.map(|active_request_handle| async move {
let result: Result<Box<RawValue>, _> = active_request_handle
.request(method, &json!(&params), error_level.into())
.await;
result
})
.collect::<FuturesUnordered<_>>()
.collect::<Vec<Result<Box<RawValue>, ProviderError>>>()
.await;
// TODO: Strings are not great keys, but we can't use RawValue or ProviderError as keys because they don't implement Hash or Eq
let mut count_map: HashMap<String, _> = HashMap::new();
let mut counts: Counter<String> = Counter::new();
let mut any_ok_with_json_result = false;
let mut any_ok_but_maybe_json_error = false;
for partial_response in responses {
if partial_response.is_ok() {
any_ok_with_json_result = true;
}
let response =
JsonRpcForwardedResponse::try_from_response_result(partial_response, id.clone());
// TODO: better key?
let s = format!("{:?}", response);
if count_map.get(&s).is_none() {
if response.is_ok() {
any_ok_but_maybe_json_error = true;
}
count_map.insert(s.clone(), response);
}
counts.update([s].into_iter());
}
for (most_common, _) in counts.most_common_ordered() {
let most_common = count_map
.remove(&most_common)
.expect("most_common key must exist");
match most_common {
Ok(x) => {
if any_ok_with_json_result && x.error.is_some() {
// this one may be an "Ok", but the json has an error inside it
continue;
}
// return the most common success
return Ok(x);
}
Err(err) => {
if any_ok_but_maybe_json_error {
// the most common is an error, but there is an Ok in here somewhere. loop to find it
continue;
}
return Err(err);
}
}
}
// TODO: what should we do if we get here? i don't think we will
unimplemented!("this shouldn't be possible")
}
pub async fn best_consensus_head_connection(
&self,
authorization: &Arc<Authorization>,
request_metadata: Option<&Arc<RequestMetadata>>,
skip: &[Arc<Web3Connection>],
min_block_needed: Option<&U64>,
) -> anyhow::Result<OpenRequestResult> {
if let Ok(without_backups) = self
._best_consensus_head_connection(
false,
authorization,
request_metadata,
skip,
min_block_needed,
)
.await
{
return Ok(without_backups);
}
self._best_consensus_head_connection(
true,
authorization,
request_metadata,
skip,
min_block_needed,
)
.await
}
/// get the best available rpc server with the consensus head block. it might have blocks after the consensus head
async fn _best_consensus_head_connection(
&self,
allow_backups: bool,
authorization: &Arc<Authorization>,
request_metadata: Option<&Arc<RequestMetadata>>,
skip: &[Arc<Web3Connection>],
min_block_needed: Option<&U64>,
) -> anyhow::Result<OpenRequestResult> {
let usable_rpcs_by_head_num_and_weight: BTreeMap<
(Option<U64>, u64),
Vec<Arc<Web3Connection>>,
> = if let Some(min_block_needed) = min_block_needed {
// need a potentially old block. check all the rpcs. prefer the most synced
let mut m = BTreeMap::new();
for x in self
.conns
.values()
.filter(|x| if allow_backups { true } else { !x.backup })
.filter(|x| !skip.contains(x))
.filter(|x| x.has_block_data(min_block_needed))
.cloned()
{
let x_head_block = x.head_block.read().clone();
match x_head_block {
None => continue,
Some(x_head) => {
let key = (Some(x_head.number()), u64::MAX - x.tier);
m.entry(key).or_insert_with(Vec::new).push(x);
}
}
}
m
} else {
// need latest. filter the synced rpcs
let synced_connections = self.synced_connections.load();
// TODO: if head_block is super old. emit an error!
let mut m = BTreeMap::new();
for x in synced_connections
.conns
.iter()
.filter(|x| !skip.contains(x))
{
let key = (None, u64::MAX - x.tier);
m.entry(key).or_insert_with(Vec::new).push(x.clone());
}
m
};
let mut earliest_retry_at = None;
for usable_rpcs in usable_rpcs_by_head_num_and_weight.into_values().rev() {
// under heavy load, it is possible for even our best server to be negative
let mut minimum = f64::MAX;
let mut maximum = f64::MIN;
// we sort on a combination of values. cache them here so that we don't do this math multiple times.
let mut available_request_map: HashMap<_, f64> = usable_rpcs
.iter()
.map(|rpc| {
// TODO: are active requests what we want? do we want a counter for requests in the last second + any actives longer than that?
// TODO: get active requests out of redis (that's definitely too slow)
// TODO: do something with hard limit instead? (but that is hitting redis too much)
let active_requests = rpc.active_requests() as f64;
let soft_limit = rpc.soft_limit as f64;
let available_requests = soft_limit - active_requests;
trace!("available requests on {}: {}", rpc, available_requests);
minimum = minimum.min(available_requests);
maximum = maximum.max(available_requests);
(rpc, available_requests)
})
.collect();
trace!("minimum available requests: {}", minimum);
trace!("maximum available requests: {}", maximum);
if maximum < 0.0 {
// TODO: if maximum < 0 and there are other tiers on the same block, we should include them now
warn!("soft limits overloaded: {} to {}", minimum, maximum)
}
// choose_multiple_weighted can't have negative numbers. shift up if any are negative
// TODO: is this a correct way to shift?
if minimum < 0.0 {
available_request_map = available_request_map
.into_iter()
.map(|(rpc, available_requests)| {
// TODO: is simple addition the right way to shift everyone?
// TODO: probably want something non-linear
// minimum is negative, so we subtract to make available requests bigger
let x = available_requests - minimum;
(rpc, x)
})
.collect()
}
let sorted_rpcs = {
if usable_rpcs.len() == 1 {
// TODO: return now instead? we shouldn't need another alloc
vec![usable_rpcs.get(0).expect("there should be 1")]
} else {
let mut rng = thread_fast_rng::thread_fast_rng();
usable_rpcs
.choose_multiple_weighted(&mut rng, usable_rpcs.len(), |rpc| {
*available_request_map
.get(rpc)
.expect("rpc should always be in available_request_map")
})
.unwrap()
.collect::<Vec<_>>()
}
};
// now that the rpcs are sorted, try to get an active request handle for one of them
for best_rpc in sorted_rpcs.into_iter() {
// increment our connection counter
match best_rpc
.try_request_handle(authorization, min_block_needed.is_none())
.await
{
Ok(OpenRequestResult::Handle(handle)) => {
trace!("opened handle: {}", best_rpc);
return Ok(OpenRequestResult::Handle(handle));
}
Ok(OpenRequestResult::RetryAt(retry_at)) => {
earliest_retry_at = earliest_retry_at.min(Some(retry_at));
}
Ok(OpenRequestResult::NotReady) => {
// TODO: log a warning? emit a stat?
}
Err(err) => {
warn!("No request handle for {}. err={:?}", best_rpc, err)
}
}
}
}
if let Some(request_metadata) = request_metadata {
request_metadata.no_servers.fetch_add(1, Ordering::Release);
}
match earliest_retry_at {
None => {
// none of the servers gave us a time to retry at
// TODO: bring this back? need to think about how to do this with `allow_backups`
// we could return an error here, but maybe waiting a second will fix the problem
// TODO: configurable max wait? the whole max request time, or just some portion?
// let handle = sorted_rpcs
// .get(0)
// .expect("at least 1 is available")
// .wait_for_request_handle(authorization, Duration::from_secs(3), false)
// .await?;
// Ok(OpenRequestResult::Handle(handle))
// TODO: should we log here?
Ok(OpenRequestResult::NotReady)
}
Some(earliest_retry_at) => {
warn!("no servers on {:?}! {:?}", self, earliest_retry_at);
Ok(OpenRequestResult::RetryAt(earliest_retry_at))
}
}
}
/// get all rpc servers that are not rate limited
/// returns servers even if they aren't fully in sync. This is useful for broadcasting signed transactions
// TODO: better type on this that can return an anyhow::Result
pub async fn all_synced_connections(
&self,
authorization: &Arc<Authorization>,
block_needed: Option<&U64>,
max_count: Option<usize>,
) -> Result<Vec<OpenRequestHandle>, Option<Instant>> {
if let Ok(without_backups) = self
._all_synced_connections(false, authorization, block_needed, max_count)
.await
{
return Ok(without_backups);
}
self._all_synced_connections(true, authorization, block_needed, max_count)
.await
}
async fn _all_synced_connections(
&self,
allow_backups: bool,
authorization: &Arc<Authorization>,
block_needed: Option<&U64>,
max_count: Option<usize>,
) -> Result<Vec<OpenRequestHandle>, Option<Instant>> {
let mut earliest_retry_at = None;
// TODO: with capacity?
let mut selected_rpcs = vec![];
let mut max_count = if max_count.is_none() {
self.conns.len()
} else {
self.conns.len().min(max_count.unwrap())
};
for connection in self.conns.values() {
if max_count == 0 {
break;
}
if !allow_backups && connection.backup {
continue;
}
if let Some(block_needed) = block_needed {
if !connection.has_block_data(block_needed) {
continue;
}
}
// check rate limits and increment our connection counter
match connection
.try_request_handle(authorization, block_needed.is_none())
.await
{
Ok(OpenRequestResult::RetryAt(retry_at)) => {
// this rpc is not available. skip it
earliest_retry_at = earliest_retry_at.min(Some(retry_at));
}
Ok(OpenRequestResult::Handle(handle)) => {
max_count -= 1;
selected_rpcs.push(handle)
}
Ok(OpenRequestResult::NotReady) => {
warn!("no request handle for {}", connection)
}
Err(err) => {
warn!(
"error getting request handle for {}. err={:?}",
connection, err
)
}
}
}
if !selected_rpcs.is_empty() {
return Ok(selected_rpcs);
}
// return the earliest retry_after (if no rpcs are synced, this will be None)
Err(earliest_retry_at)
}
/// be sure there is a timeout on this or it might loop forever
pub async fn try_send_best_consensus_head_connection(
&self,
authorization: &Arc<Authorization>,
request: JsonRpcRequest,
request_metadata: Option<&Arc<RequestMetadata>>,
min_block_needed: Option<&U64>,
) -> anyhow::Result<JsonRpcForwardedResponse> {
let mut skip_rpcs = vec![];
// TODO: maximum retries? right now its the total number of servers
loop {
if skip_rpcs.len() == self.conns.len() {
// no servers to try
break;
}
match self
.best_consensus_head_connection(
authorization,
request_metadata,
&skip_rpcs,
min_block_needed,
)
.await?
{
OpenRequestResult::Handle(active_request_handle) => {
// save the rpc in case we get an error and want to retry on another server
skip_rpcs.push(active_request_handle.clone_connection());
if let Some(request_metadata) = request_metadata {
// TODO: request_metadata.backend_requests instead of skip_rpcs
request_metadata
.backend_requests
.lock()
.push(active_request_handle.clone_connection());
}
// TODO: get the log percent from the user data
let response_result = active_request_handle
.request(
&request.method,
&json!(request.params),
RequestRevertHandler::Save,
)
.await;
match JsonRpcForwardedResponse::try_from_response_result(
response_result,
request.id.clone(),
) {
Ok(response) => {
if let Some(error) = &response.error {
// trace!(?response, "rpc error");
if let Some(request_metadata) = request_metadata {
request_metadata
.error_response
.store(true, Ordering::Release);
}
// some errors should be retried on other nodes
let error_msg = error.message.as_str();
// different providers do different codes. check all of them
// TODO: there's probably more strings to add here
let rate_limit_substrings = ["limit", "exceeded"];
for rate_limit_substr in rate_limit_substrings {
if error_msg.contains(rate_limit_substr) {
warn!("rate limited by {}", skip_rpcs.last().unwrap());
continue;
}
}
match error.code {
-32000 => {
// TODO: regex?
let retry_prefixes = [
"header not found",
"header for hash not found",
"missing trie node",
"node not started",
"RPC timeout",
];
for retry_prefix in retry_prefixes {
if error_msg.starts_with(retry_prefix) {
continue;
}
}
}
-32601 => {
let error_msg = error.message.as_str();
if error_msg.starts_with("the method")
&& error_msg.ends_with("is not available")
{
continue;
}
}
_ => {}
}
} else {
// trace!(?response, "rpc success");
}
return Ok(response);
}
Err(err) => {
let rpc = skip_rpcs
.last()
.expect("there must have been a provider if we got an error");
// TODO: emit a stat. if a server is getting skipped a lot, something is not right
debug!(
"Backend server error on {}! Retrying on another. err={:?}",
rpc, err
);
// TODO: sleep how long? until synced_connections changes or rate limits are available
// sleep(Duration::from_millis(100)).await;
continue;
}
}
}
OpenRequestResult::RetryAt(retry_at) => {
// TODO: move this to a helper function
// sleep (TODO: with a lock?) until our rate limits should be available
// TODO: if a server catches up sync while we are waiting, we could stop waiting
warn!("All rate limits exceeded. Sleeping until {:?}", retry_at);
// TODO: have a separate column for rate limited?
if let Some(request_metadata) = request_metadata {
request_metadata.no_servers.fetch_add(1, Ordering::Release);
}
sleep_until(retry_at).await;
continue;
}
OpenRequestResult::NotReady => {
if let Some(request_metadata) = request_metadata {
request_metadata.no_servers.fetch_add(1, Ordering::Release);
}
break;
}
}
}
// TODO: do we need this here, or do we do it somewhere else?
if let Some(request_metadata) = request_metadata {
request_metadata
.error_response
.store(true, Ordering::Release);
}
let num_conns = self.conns.len();
error!("No servers synced ({} known)", num_conns);
Err(anyhow::anyhow!("No servers synced ({} known)", num_conns))
}
/// be sure there is a timeout on this or it might loop forever
pub async fn try_send_all_synced_connections(
&self,
authorization: &Arc<Authorization>,
request: &JsonRpcRequest,
request_metadata: Option<Arc<RequestMetadata>>,
block_needed: Option<&U64>,
error_level: Level,
max_count: Option<usize>,
) -> anyhow::Result<JsonRpcForwardedResponse> {
loop {
match self
.all_synced_connections(authorization, block_needed, max_count)
.await
{
Ok(active_request_handles) => {
// TODO: benchmark this compared to waiting on unbounded futures
// TODO: do something with this handle?
// TODO: this is not working right. simplify
if let Some(request_metadata) = request_metadata {
request_metadata
.backend_requests
.lock()
.extend(active_request_handles.iter().map(|x| x.clone_connection()));
}
return self
.try_send_parallel_requests(
active_request_handles,
request.id.clone(),
request.method.as_ref(),
request.params.as_ref(),
error_level,
)
.await;
}
Err(None) => {
warn!("No servers in sync on {:?}! Retrying", self);
if let Some(request_metadata) = &request_metadata {
request_metadata.no_servers.fetch_add(1, Ordering::Release);
}
// TODO: i don't think this will ever happen
// TODO: return a 502? if it does?
// return Err(anyhow::anyhow!("no available rpcs!"));
// TODO: sleep how long?
// TODO: subscribe to something in ConsensusConnections instead
sleep(Duration::from_millis(200)).await;
continue;
}
Err(Some(retry_at)) => {
// TODO: move this to a helper function
// sleep (TODO: with a lock?) until our rate limits should be available
// TODO: if a server catches up sync while we are waiting, we could stop waiting
warn!("All rate limits exceeded. Sleeping");
if let Some(request_metadata) = &request_metadata {
request_metadata.no_servers.fetch_add(1, Ordering::Release);
}
sleep_until(retry_at).await;
continue;
}
}
}
}
pub async fn try_proxy_connection(
&self,
proxy_mode: ProxyMode,
authorization: &Arc<Authorization>,
request: JsonRpcRequest,
request_metadata: Option<&Arc<RequestMetadata>>,
min_block_needed: Option<&U64>,
) -> anyhow::Result<JsonRpcForwardedResponse> {
match proxy_mode {
ProxyMode::Best => {
self.try_send_best_consensus_head_connection(
authorization,
request,
request_metadata,
min_block_needed,
)
.await
}
ProxyMode::Fastest(x) => todo!("Fastest"),
ProxyMode::Versus => todo!("Versus"),
}
}
}
impl fmt::Debug for Web3Connections {
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("Web3Connections")
.field("conns", &self.conns)
.finish_non_exhaustive()
}
}
impl Serialize for Web3Connections {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
let mut state = serializer.serialize_struct("Web3Connections", 6)?;
let conns: Vec<&Web3Connection> = self.conns.values().map(|x| x.as_ref()).collect();
state.serialize_field("conns", &conns)?;
let synced_connections = &**self.synced_connections.load();
state.serialize_field("synced_connections", synced_connections)?;
self.block_hashes.sync();
self.block_numbers.sync();
state.serialize_field("block_hashes_count", &self.block_hashes.entry_count())?;
state.serialize_field("block_hashes_size", &self.block_hashes.weighted_size())?;
state.serialize_field("block_numbers_count", &self.block_numbers.entry_count())?;
state.serialize_field("block_numbers_size", &self.block_numbers.weighted_size())?;
state.end()
}
}
mod tests {
// TODO: why is this allow needed? does tokio::test get in the way somehow?
#![allow(unused_imports)]
use super::*;
use crate::rpcs::{
blockchain::{ConsensusFinder, SavedBlock},
connection::ProviderState,
provider::Web3Provider,
};
use ethers::types::{Block, U256};
use log::{trace, LevelFilter};
use parking_lot::RwLock;
use std::time::{SystemTime, UNIX_EPOCH};
use tokio::sync::RwLock as AsyncRwLock;
#[tokio::test]
async fn test_server_selection_by_height() {
// TODO: do this better. can test_env_logger and tokio test be stacked?
let _ = env_logger::builder()
.filter_level(LevelFilter::Error)
.filter_module("web3_proxy", LevelFilter::Trace)
.is_test(true)
.try_init();
let now: U256 = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap()
.as_secs()
.into();
let lagged_block = Block {
hash: Some(H256::random()),
number: Some(0.into()),
timestamp: now - 1,
..Default::default()
};
let head_block = Block {
hash: Some(H256::random()),
number: Some(1.into()),
parent_hash: lagged_block.hash.unwrap(),
timestamp: now,
..Default::default()
};
let lagged_block = Arc::new(lagged_block);
let head_block = Arc::new(head_block);
// TODO: write a impl From for Block -> BlockId?
let mut lagged_block: SavedBlock = lagged_block.into();
let mut head_block: SavedBlock = head_block.into();
let block_data_limit = u64::MAX;
let head_rpc = Web3Connection {
name: "synced".to_string(),
db_conn: None,
display_name: None,
url: "ws://example.com/synced".to_string(),
http_client: None,
active_requests: 0.into(),
frontend_requests: 0.into(),
internal_requests: 0.into(),
provider_state: AsyncRwLock::new(ProviderState::Ready(Arc::new(Web3Provider::Mock))),
hard_limit: None,
soft_limit: 1_000,
automatic_block_limit: true,
backup: false,
block_data_limit: block_data_limit.into(),
tier: 0,
head_block: RwLock::new(Some(head_block.clone())),
open_request_handle_metrics: Arc::new(Default::default()),
};
let lagged_rpc = Web3Connection {
name: "lagged".to_string(),
db_conn: None,
display_name: None,
url: "ws://example.com/lagged".to_string(),
http_client: None,
active_requests: 0.into(),
frontend_requests: 0.into(),
internal_requests: 0.into(),
provider_state: AsyncRwLock::new(ProviderState::Ready(Arc::new(Web3Provider::Mock))),
hard_limit: None,
soft_limit: 1_000,
automatic_block_limit: false,
backup: false,
block_data_limit: block_data_limit.into(),
tier: 0,
head_block: RwLock::new(Some(lagged_block.clone())),
open_request_handle_metrics: Arc::new(Default::default()),
};
assert!(head_rpc.has_block_data(&lagged_block.number()));
assert!(head_rpc.has_block_data(&head_block.number()));
assert!(lagged_rpc.has_block_data(&lagged_block.number()));
assert!(!lagged_rpc.has_block_data(&head_block.number()));
let head_rpc = Arc::new(head_rpc);
let lagged_rpc = Arc::new(lagged_rpc);
let conns = HashMap::from([
(head_rpc.name.clone(), head_rpc.clone()),
(lagged_rpc.name.clone(), lagged_rpc.clone()),
]);
let conns = Web3Connections {
conns,
synced_connections: Default::default(),
pending_transactions: Cache::builder()
.max_capacity(10_000)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
block_hashes: Cache::builder()
.max_capacity(10_000)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
block_numbers: Cache::builder()
.max_capacity(10_000)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
min_head_rpcs: 1,
min_sum_soft_limit: 1,
};
let authorization = Arc::new(Authorization::internal(None).unwrap());
let (head_block_sender, _head_block_receiver) =
watch::channel::<ArcBlock>(Default::default());
let mut connection_heads = ConsensusFinder::default();
// process None so that
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
None,
lagged_rpc.clone(),
&head_block_sender,
&None,
)
.await
.unwrap();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
None,
head_rpc.clone(),
&head_block_sender,
&None,
)
.await
.unwrap();
// no head block because the rpcs haven't communicated through their channels
assert!(conns.head_block_hash().is_none());
// all_backend_connections gives everything regardless of sync status
assert_eq!(
conns
.all_synced_connections(&authorization, None, None)
.await
.unwrap()
.len(),
2
);
// best_synced_backend_connection requires servers to be synced with the head block
let x = conns
.best_consensus_head_connection(&authorization, None, &[], None)
.await
.unwrap();
dbg!(&x);
assert!(matches!(x, OpenRequestResult::NotReady));
// add lagged blocks to the conns. both servers should be allowed
lagged_block.block = conns.save_block(lagged_block.block, true).await.unwrap();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
Some(lagged_block.clone()),
lagged_rpc,
&head_block_sender,
&None,
)
.await
.unwrap();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
Some(lagged_block.clone()),
head_rpc.clone(),
&head_block_sender,
&None,
)
.await
.unwrap();
assert_eq!(conns.num_synced_rpcs(), 2);
// add head block to the conns. lagged_rpc should not be available
head_block.block = conns.save_block(head_block.block, true).await.unwrap();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
Some(head_block.clone()),
head_rpc,
&head_block_sender,
&None,
)
.await
.unwrap();
assert_eq!(conns.num_synced_rpcs(), 1);
assert!(matches!(
conns
.best_consensus_head_connection(&authorization, None, &[], None)
.await,
Ok(OpenRequestResult::Handle(_))
));
assert!(matches!(
conns
.best_consensus_head_connection(&authorization, None, &[], Some(&0.into()))
.await,
Ok(OpenRequestResult::Handle(_))
));
assert!(matches!(
conns
.best_consensus_head_connection(&authorization, None, &[], Some(&1.into()))
.await,
Ok(OpenRequestResult::Handle(_))
));
// future block should not get a handle
assert!(matches!(
conns
.best_consensus_head_connection(&authorization, None, &[], Some(&2.into()))
.await,
Ok(OpenRequestResult::NotReady)
));
}
#[tokio::test]
async fn test_server_selection_by_archive() {
// TODO: do this better. can test_env_logger and tokio test be stacked?
let _ = env_logger::builder()
.filter_level(LevelFilter::Error)
.filter_module("web3_proxy", LevelFilter::Trace)
.is_test(true)
.try_init();
let now: U256 = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap()
.as_secs()
.into();
let head_block = Block {
hash: Some(H256::random()),
number: Some(1_000_000.into()),
parent_hash: H256::random(),
timestamp: now,
..Default::default()
};
let head_block: SavedBlock = Arc::new(head_block).into();
let pruned_rpc = Web3Connection {
name: "pruned".to_string(),
db_conn: None,
display_name: None,
url: "ws://example.com/pruned".to_string(),
http_client: None,
active_requests: 0.into(),
frontend_requests: 0.into(),
internal_requests: 0.into(),
provider_state: AsyncRwLock::new(ProviderState::Ready(Arc::new(Web3Provider::Mock))),
hard_limit: None,
soft_limit: 3_000,
automatic_block_limit: false,
backup: false,
block_data_limit: 64.into(),
tier: 1,
head_block: RwLock::new(Some(head_block.clone())),
open_request_handle_metrics: Arc::new(Default::default()),
};
let archive_rpc = Web3Connection {
name: "archive".to_string(),
db_conn: None,
display_name: None,
url: "ws://example.com/archive".to_string(),
http_client: None,
active_requests: 0.into(),
frontend_requests: 0.into(),
internal_requests: 0.into(),
provider_state: AsyncRwLock::new(ProviderState::Ready(Arc::new(Web3Provider::Mock))),
hard_limit: None,
soft_limit: 1_000,
automatic_block_limit: false,
backup: false,
block_data_limit: u64::MAX.into(),
tier: 2,
head_block: RwLock::new(Some(head_block.clone())),
open_request_handle_metrics: Arc::new(Default::default()),
};
assert!(pruned_rpc.has_block_data(&head_block.number()));
assert!(archive_rpc.has_block_data(&head_block.number()));
assert!(!pruned_rpc.has_block_data(&1.into()));
assert!(archive_rpc.has_block_data(&1.into()));
let pruned_rpc = Arc::new(pruned_rpc);
let archive_rpc = Arc::new(archive_rpc);
let conns = HashMap::from([
(pruned_rpc.name.clone(), pruned_rpc.clone()),
(archive_rpc.name.clone(), archive_rpc.clone()),
]);
let conns = Web3Connections {
conns,
synced_connections: Default::default(),
pending_transactions: Cache::builder()
.max_capacity(10)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
block_hashes: Cache::builder()
.max_capacity(10)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
block_numbers: Cache::builder()
.max_capacity(10)
.build_with_hasher(hashbrown::hash_map::DefaultHashBuilder::default()),
min_head_rpcs: 1,
min_sum_soft_limit: 3_000,
};
let authorization = Arc::new(Authorization::internal(None).unwrap());
let (head_block_sender, _head_block_receiver) =
watch::channel::<ArcBlock>(Default::default());
let mut connection_heads = ConsensusFinder::default();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
Some(head_block.clone()),
pruned_rpc.clone(),
&head_block_sender,
&None,
)
.await
.unwrap();
conns
.process_block_from_rpc(
&authorization,
&mut connection_heads,
Some(head_block.clone()),
archive_rpc.clone(),
&head_block_sender,
&None,
)
.await
.unwrap();
assert_eq!(conns.num_synced_rpcs(), 2);
// best_synced_backend_connection requires servers to be synced with the head block
let best_head_server = conns
.best_consensus_head_connection(&authorization, None, &[], Some(&head_block.number()))
.await;
assert!(matches!(
best_head_server.unwrap(),
OpenRequestResult::Handle(_)
));
let best_archive_server = conns
.best_consensus_head_connection(&authorization, None, &[], Some(&1.into()))
.await;
match best_archive_server {
Ok(OpenRequestResult::Handle(x)) => {
assert_eq!(x.clone_connection().name, "archive".to_string())
}
x => {
error!("unexpected result: {:?}", x);
}
}
}
}