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use crate::helpers::{deserialize, serialize};
use crate::network::api::{
ApiStreamRequest, ApiStreamRequestPayload, ApiStreamResponse, ApiStreamResponsePayload,
WsWriteMsg,
};
use crate::network::handshake::HandshakeSecret;
use crate::server::proxy::handlers::AppStateExt;
use crate::store::state_machine::sqlite::state_machine::Query;
use crate::{Client, Error};
use fastwebsockets::{FragmentCollectorRead, Frame, OpCode, Payload, upgrade};
use std::ops::Deref;
use tokio::task;
use tracing::{debug, error};
pub async fn handle_socket(
state: AppStateExt,
socket: upgrade::UpgradeFut,
) -> Result<(), fastwebsockets::WebSocketError> {
let mut ws = socket.await?;
ws.set_auto_close(true);
if let Err(err) = HandshakeSecret::server(&mut ws, state.secret_api.as_bytes()).await {
error!("Error during WebSocket handshake: {}", err);
ws.write_frame(Frame::close(1000, b"Invalid Handshake"))
.await?;
return Ok(());
};
let (tx_write, rx_write) = flume::bounded::<WsWriteMsg>(1);
// let (tx_write, rx_write) = flume::unbounded::<WsWriteMsg>();
// let (tx_read, rx_read) = flume::unbounded();
// TODO splitting needs `unstable-split` feature right now but is about to be stabilized soon
let (rx, mut write) = ws.split(tokio::io::split);
// IMPORTANT: the reader is NOT CANCEL SAFE in v0.8!
let mut read = FragmentCollectorRead::new(rx);
let handle_write = task::spawn(async move {
while let Ok(req) = rx_write.recv_async().await {
match req {
WsWriteMsg::Payload(resp) => {
let bytes = serialize(&resp).unwrap();
let frame = Frame::binary(Payload::Borrowed(&bytes));
if let Err(err) = write.write_frame(frame).await {
error!("Error during WebSocket write: {}", err);
// // if we have a WebSocket error, save all open requests into the client_buffer
// let payload = bincode::serialize(&resp).unwrap();
// buf_tx
// .send_async(payload)
// .await
// .expect("client_buffer to always be working");
break;
}
}
WsWriteMsg::Break => {
// we ignore any errors here since it may be possible that the reader
// has closed already - we just try a graceful connection close
let _ = write
.write_frame(Frame::close(1000, b"Invalid Request"))
.await;
debug!("server stream break message");
break;
}
}
}
debug!("server stream exiting");
});
while let Ok(frame) = read
.read_frame(&mut |frame| async move {
// TODO obligated sends should be auto ping / pong / close ? -> verify!
debug!(
"Received obligated send in stream client: OpCode: {:?}: {:?}",
frame.opcode.clone(),
frame.payload
);
Ok::<(), Error>(())
})
.await
{
let req = match frame.opcode {
OpCode::Close => {
debug!("received Close frame in server stream");
break;
}
OpCode::Binary => {
let bytes = frame.payload.deref();
match deserialize::<ApiStreamRequest>(bytes) {
Ok(req) => req,
Err(err) => {
error!("Error deserializing ApiStreamRequest: {:?}", err);
// ws.write_frame(Frame::close(1000, b"Error deserializing ApiStreamRequest"))
// .await?;
let _ = tx_write.send_async(WsWriteMsg::Break).await;
break;
}
}
}
_ => {
let _ = tx_write.send_async(WsWriteMsg::Break).await;
// ws.write_frame(Frame::close(1000, b"Invalid Request"))
// .await?;
break;
}
};
let state = state.clone();
let tx_write = tx_write.clone();
task::spawn(async move {
let client = &state.client;
// exchange orig req id for our own to avoid conflicts
let request_id = req.request_id;
let res = match req.payload {
ApiStreamRequestPayload::Execute(sql) => {
let res = client.execute(sql.sql, sql.params).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Execute(res),
}
}
ApiStreamRequestPayload::ExecuteReturning(query) => {
match client.execute_returning_req(query.clone()).await {
Ok(res) => ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::ExecuteReturning(Ok(res)),
},
Err(err) => {
if client
.was_leader_update_error(
&err,
&client.inner.leader_db,
&client.inner.tx_client_db,
)
.await
{
let res = client.execute_returning_req(query).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::ExecuteReturning(res),
}
} else {
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::ExecuteReturning(Err(err)),
}
}
}
}
}
ApiStreamRequestPayload::Transaction(queries) => {
let res = match client.txn_execute(queries.clone()).await {
Ok(res) => Ok(res),
Err(err) => {
if client
.was_leader_update_error(
&err,
&client.inner.leader_db,
&client.inner.tx_client_db,
)
.await
{
client.txn_execute(queries).await
} else {
Err(err)
}
}
};
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Transaction(res),
}
}
ApiStreamRequestPayload::QueryConsistent(q) => {
query(client, request_id, q, true).await
}
ApiStreamRequestPayload::Batch(sql) => {
let res = client.batch(sql).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Batch(res),
}
}
ApiStreamRequestPayload::Migrate(migrations) => {
let res = match client.migrate_execute(migrations.clone()).await {
Ok(res) => Ok(res),
Err(err) => {
if client
.was_leader_update_error(
&err,
&client.inner.leader_db,
&client.inner.tx_client_db,
)
.await
{
client.migrate_execute(migrations).await
} else {
Err(err)
}
}
};
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Migrate(res),
}
}
ApiStreamRequestPayload::Backup(_node_id) => {
let res = client.backup().await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Backup(res),
}
}
ApiStreamRequestPayload::Query(q) => query(client, request_id, q, false).await,
ApiStreamRequestPayload::KV(cache_req) => {
let res = client.cache_req_retry(cache_req, false).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::KV(res),
}
}
ApiStreamRequestPayload::KVGet(cache_req) => {
let res = client.cache_req_retry(cache_req, true).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::KV(res),
}
}
ApiStreamRequestPayload::LockAwait(cache_req) => {
match client.lock_req_retry(cache_req, true).await {
Ok(res) => ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Lock(res),
},
Err(_) => {
todo!(
"how should be handle await errors? wrap state inside inner result just for the proxy or retry endlessly?"
)
} // Err(err) => ApiStreamResponse {
// request_id,
// result: ApiStreamResponsePayload::Lock(Err(err)),
// },
}
}
ApiStreamRequestPayload::Notify(cache_req) => {
let res = client.notify_req(cache_req).await;
ApiStreamResponse {
request_id,
result: ApiStreamResponsePayload::Notify(res),
}
}
};
if let Err(err) = tx_write.send_async(WsWriteMsg::Payload(res)).await {
error!("Error sending payload to tx_write: {}", err);
}
});
}
// ignore the result in case the writer has already exited and drop the channel
// on purpose to make sure a maybe still running writer catches it
let _ = tx_write.send_async(WsWriteMsg::Break).await;
drop(tx_write);
handle_write.await.unwrap();
Ok(())
}
#[inline]
async fn query(
client: &Client,
request_id: usize,
query: Query,
consistent: bool,
) -> ApiStreamResponse {
let res = match client.query_remote_req(query.clone(), consistent).await {
Ok(res) => Ok(res),
Err(err) => {
if client
.was_leader_update_error(&err, &client.inner.leader_db, &client.inner.tx_client_db)
.await
{
client.query_remote_req(query, consistent).await
} else {
Err(err)
}
}
};
let result = if consistent {
ApiStreamResponsePayload::QueryConsistent(res)
} else {
ApiStreamResponsePayload::Query(res)
};
ApiStreamResponse { request_id, result }
}