zelo72
/
flodgatt
mirror of https://github.com/mastodon/flodgatt
1
0
Fork 0
Code Issues Releases Wiki Activity

Implement faster buffered input 

This commit implements a modified ring buffer for input from Redis.
Specifically, Flodgatt now limits the amount of data it fetches from
Redis in one syscall to 8 KiB (two pages on most systems). Flodgatt
will process all complete messages it receives from Redis and then
re-use the same buffer for the next time it retrieves data.  If
Flodgatt received a partial message, it will copy the partial message
to the beginning of the buffer before its next read.

This change has little effect on Flodgatt under light load (because it
was rare for Redis to have more than 8 KiB of messages available at
any one time).  However, my hope is that this will significantly
reduce memory use on the largest instances.
This commit is contained in:
Daniel Sockwell 2020-04-25 16:40:37 -04:00
parent d8b07b4b03
commit 3782ab13a3
12 changed files with 250 additions and 234 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
Cargo.lock generated
View File

@ -416,7 +416,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "flodgatt"
version = "0.9.4"
version = "0.9.5"
dependencies = [
"criterion 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
"dotenv 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",

2
Cargo.toml
View File

@ -1,7 +1,7 @@
[package]
name = "flodgatt"
description = "A blazingly fast drop-in replacement for the Mastodon streaming api server"
version = "0.9.4"
version = "0.9.5"
authors = ["Daniel Long Sockwell <daniel@codesections.com", "Julian Laubstein <contact@julianlaubstein.de>"]
edition = "2018"

74
benches/parse_redis.rs
View File

@ -1,9 +1,5 @@
use criterion::{black_box, criterion_group, criterion_main, Criterion};
use flodgatt::{
event::*,
request::{Content::*, Reach::*, Stream::*, Timeline},
response::{RedisMsg, RedisParseOutput},
};
use flodgatt::response::{RedisMsg, RedisParseOutput};
use lru::LruCache;
use std::convert::TryFrom;
@ -16,27 +12,27 @@ fn parse_long_redis_input<'a>(input: &'a str) -> RedisMsg<'a> {
}
}
fn parse_to_timeline(msg: RedisMsg) -> Timeline {
let trimmed_tl_txt = &msg.timeline_txt["timeline:".len()..];
let tl = Timeline::from_redis_text(trimmed_tl_txt, &mut LruCache::new(1000)).unwrap();
assert_eq!(tl, Timeline(User(Id(1)), Federated, All));
tl
}
fn parse_to_checked_event(msg: RedisMsg) -> EventKind {
EventKind::TypeSafe(serde_json::from_str(msg.event_txt).unwrap())
}
// fn parse_to_timeline(msg: RedisMsg) -> Timeline {
// let trimmed_tl_txt = &msg.timeline_txt["timeline:".len()..];
// let tl = Timeline::from_redis_text(trimmed_tl_txt, &mut LruCache::new(1000)).unwrap();
// assert_eq!(tl, Timeline(User(Id(1)), Federated, All));
// tl
// }
// fn parse_to_checked_event(msg: RedisMsg) -> EventKind {
// EventKind::TypeSafe(serde_json::from_str(msg.event_txt).unwrap())
// }
fn parse_to_dyn_event(msg: RedisMsg) -> EventKind {
EventKind::Dynamic(serde_json::from_str(msg.event_txt).unwrap())
}
// fn parse_to_dyn_event(msg: RedisMsg) -> EventKind {
// EventKind::Dynamic(serde_json::from_str(msg.event_txt).unwrap())
// }
fn redis_msg_to_event_string(msg: RedisMsg) -> String {
msg.event_txt.to_string()
}
// fn redis_msg_to_event_string(msg: RedisMsg) -> String {
// msg.event_txt.to_string()
// }
fn string_to_checked_event(event_txt: &String) -> EventKind {
EventKind::TypeSafe(serde_json::from_str(event_txt).unwrap())
}
// fn string_to_checked_event(event_txt: &String) -> EventKind {
// EventKind::TypeSafe(serde_json::from_str(event_txt).unwrap())
// }
fn criterion_benchmark(c: &mut Criterion) {
let input = ONE_MESSAGE_FOR_THE_USER_TIMLINE_FROM_REDIS;
@ -46,25 +42,25 @@ fn criterion_benchmark(c: &mut Criterion) {
b.iter(|| black_box(parse_long_redis_input(input)))
});
let msg = parse_long_redis_input(input);
group.bench_function("parse RedisMsg to Timeline", |b| {
b.iter(|| black_box(parse_to_timeline(msg.clone())))
});
// let msg = parse_long_redis_input(input);
// group.bench_function("parse RedisMsg to Timeline", |b| {
// b.iter(|| black_box(parse_to_timeline(msg.clone())))
// });
group.bench_function("parse RedisMsg -> DynamicEvent", |b| {
b.iter(|| black_box(parse_to_dyn_event(msg.clone())))
});
// group.bench_function("parse RedisMsg -> DynamicEvent", |b| {
// b.iter(|| black_box(parse_to_dyn_event(msg.clone())))
// });
group.bench_function("parse RedisMsg -> CheckedEvent", |b| {
b.iter(|| black_box(parse_to_checked_event(msg.clone())))
});
// group.bench_function("parse RedisMsg -> CheckedEvent", |b| {
// b.iter(|| black_box(parse_to_checked_event(msg.clone())))
// });
group.bench_function("parse RedisMsg -> String -> CheckedEvent", |b| {
b.iter(|| {
let txt = black_box(redis_msg_to_event_string(msg.clone()));
black_box(string_to_checked_event(&txt));
})
});
// group.bench_function("parse RedisMsg -> String -> CheckedEvent", |b| {
// b.iter(|| {
// let txt = black_box(redis_msg_to_event_string(msg.clone()));
// black_box(string_to_checked_event(&txt));
// })
// });
}
criterion_group!(benches, criterion_benchmark);

2
src/err.rs
View File

@ -15,7 +15,7 @@ pub enum Error {
impl Error {
pub fn log(msg: impl fmt::Display) {
eprintln!("{}", msg);
eprintln!("Error: {}", msg);
}
}

1
src/request/timeline.rs
View File

@ -35,7 +35,6 @@ impl Timeline {
}
pub(crate) fn to_redis_raw_timeline(&self, hashtag: Option<&String>) -> Result<String> {
// TODO -- does this need to account for namespaces?
use {Content::*, Error::*, Reach::*, Stream::*};
Ok(match self {

2
src/response.rs
View File

@ -14,4 +14,4 @@ mod stream;
pub use redis::Error;
#[cfg(feature = "bench")]
pub use redis::msg::{RedisMsg, RedisParseOutput};
pub use redis::{RedisMsg, RedisParseOutput};

83
src/response/redis.rs
View File

@ -7,6 +7,9 @@ pub(self) use connection::RedisConn;
pub use manager::Error;
pub use manager::Manager;
#[cfg(feature = "bench")]
pub use msg::{RedisMsg, RedisParseOutput};
use connection::RedisConnErr;
use msg::RedisParseErr;
@ -16,44 +19,50 @@ enum RedisCmd {
}
impl RedisCmd {
fn into_sendable(self, tl: &str) -> (Vec<u8>, Vec<u8>) {
fn into_sendable(self, timelines: &[String]) -> (Vec<u8>, Vec<u8>) {
match self {
RedisCmd::Subscribe => (
[
b"*2\r\n$9\r\nsubscribe\r\n$",
tl.len().to_string().as_bytes(),
b"\r\n",
tl.as_bytes(),
b"\r\n",
]
.concat(),
[
b"*3\r\n$3\r\nSET\r\n$",
(tl.len() + "subscribed:".len()).to_string().as_bytes(),
b"\r\nsubscribed:",
tl.to_string().as_bytes(),
b"\r\n$1\r\n1\r\n",
]
.concat(),
),
RedisCmd::Unsubscribe => (
[
b"*2\r\n$11\r\nunsubscribe\r\n$",
tl.len().to_string().as_bytes(),
b"\r\n",
tl.as_bytes(),
b"\r\n",
]
.concat(),
[
b"*3\r\n$3\r\nSET\r\n$",
(tl.len() + "subscribed:".len()).to_string().as_bytes(),
b"\r\nsubscribed:",
tl.to_string().as_bytes(),
b"\r\n$1\r\n0\r\n",
]
.concat(),
),
RedisCmd::Subscribe => {
let primary = {
let mut cmd = format!("*{}\r\n$9\r\nsubscribe\r\n", 1 + timelines.len());
for tl in timelines {
cmd.push_str(&format!("${}\r\n{}\r\n", tl.len(), tl));
}
cmd
};
let secondary = {
let mut cmd = format!("*{}\r\n$4\r\nMSET\r\n", 1 + timelines.len());
for tl in timelines {
cmd.push_str(&format!(
"${}\r\nsubscribed:{}\r\n$1\r\n$1\r\n",
"subscribed:".len() + tl.len(),
tl
));
}
cmd
};
(primary.as_bytes().to_vec(), secondary.as_bytes().to_vec())
}
RedisCmd::Unsubscribe => {
let primary = {
let mut cmd = format!("*{}\r\n$11\r\nunsubscribe\r\n", 1 + timelines.len());
for tl in timelines {
cmd.push_str(&format!("${}\r\n{}\r\n", tl.len(), tl));
}
cmd
};
let secondary = {
let mut cmd = format!("*{}\r\n$4\r\nMSET\r\n", 1 + timelines.len());
for tl in timelines {
cmd.push_str(&format!(
"${}\r\nsubscribed:{}\r\n$1\r\n$0\r\n",
"subscribed:".len() + tl.len(),
tl
));
}
cmd
};
(primary.as_bytes().to_vec(), secondary.as_bytes().to_vec())
}
}
}
}

141
src/response/redis/connection.rs
View File

@ -1,19 +1,15 @@
mod err;
pub(crate) use err::RedisConnErr;
use super::msg::{RedisParseErr, RedisParseOutput};
use super::Error as ManagerErr;
use super::Event;
use super::RedisCmd;
use crate::config::Redis;
use crate::request::Timeline;
use futures::{Async, Poll};
use lru::LruCache;
use std::convert::{TryFrom, TryInto};
use std::io::{self, Read, Write};
use std::net::TcpStream;
use std::str;
use std::time::Duration;
type Result<T> = std::result::Result<T, RedisConnErr>;
@ -22,11 +18,13 @@ type Result<T> = std::result::Result<T, RedisConnErr>;
pub(super) struct RedisConn {
primary: TcpStream,
secondary: TcpStream,
redis_namespace: Option<String>,
tag_id_cache: LruCache<String, i64>,
pub(super) namespace: Option<String>,
// TODO: eventually, it might make sense to have Mastodon publish to timelines with
// the tag number instead of the tag name. This would save us from dealing
// with a cache here and would be consistent with how lists/users are handled.
pub(super) tag_id_cache: LruCache<String, i64>,
tag_name_cache: LruCache<i64, String>,
redis_input: Vec<u8>,
cursor: usize,
pub(super) input: Vec<u8>,
}
impl RedisConn {
@ -36,79 +34,31 @@ impl RedisConn {
let conn = Self::new_connection(&addr, redis_cfg.password.as_ref())?;
conn.set_nonblocking(true)
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
let redis_conn = Self {
Ok(Self {
primary: conn,
secondary: Self::new_connection(&addr, redis_cfg.password.as_ref())?,
tag_id_cache: LruCache::new(1000),
tag_name_cache: LruCache::new(1000),
// TODO: eventually, it might make sense to have Mastodon publish to timelines with
// the tag number instead of the tag name. This would save us from dealing
// with a cache here and would be consistent with how lists/users are handled.
redis_namespace: redis_cfg.namespace.clone().0,
redis_input: vec![0_u8; 5000],
cursor: 0,
};
Ok(redis_conn)
namespace: redis_cfg.namespace.clone().0,
input: vec![47_u8; 10_000], // TODO - set to something reasonable
})
}
pub(super) fn poll_redis(&mut self) -> Poll<Option<(Timeline, Event)>, ManagerErr> {
loop {
match self.primary.read(&mut self.redis_input[self.cursor..]) {
Ok(n) => {
self.cursor += n;
if self.redis_input.len() - 1 == self.cursor {
self.redis_input.resize(self.redis_input.len() * 2, 0);
} else {
break;
}
}
Err(e) if matches!(e.kind(), io::ErrorKind::WouldBlock) => {
break;
}
Err(e) => break log::error!("{}", e),
};
pub(super) fn poll_redis(&mut self, start: usize) -> Poll<usize, ManagerErr> {
const BLOCK: usize = 8192;
if self.input.len() <= start + BLOCK {
self.input.resize(self.input.len() * 2, 0);
log::info!("Resizing input buffer. (Old input was {} bytes)", start);
}
// at this point, we have the raw bytes; now, parse a msg
let input = &self.redis_input[..self.cursor];
let (input, invalid_bytes) = str::from_utf8(&input)
.map(|input| (input, "".as_bytes()))
.unwrap_or_else(|e| {
let (valid, invalid) = input.split_at(e.valid_up_to());
(str::from_utf8(valid).expect("Guaranteed by ^^^^"), invalid)
});
use {Async::*, RedisParseOutput::*};
let (res, leftover) = match RedisParseOutput::try_from(input) {
Ok(Msg(msg)) => match &self.redis_namespace {
Some(ns) if msg.timeline_txt.starts_with(&[ns, ":timeline:"].concat()) => {
let trimmed_tl = &msg.timeline_txt[ns.len() + ":timeline:".len()..];
let tl = Timeline::from_redis_text(trimmed_tl, &mut self.tag_id_cache)?;
let event = msg.event_txt.try_into()?;
(Ok(Ready(Some((tl, event)))), (msg.leftover_input))
}
None => {
let trimmed_tl = &msg.timeline_txt["timeline:".len()..];
let tl = Timeline::from_redis_text(trimmed_tl, &mut self.tag_id_cache)?;
let event = msg.event_txt.try_into()?;
(Ok(Ready(Some((tl, event)))), (msg.leftover_input))
}
Some(_non_matching_namespace) => (Ok(Ready(None)), msg.leftover_input),
},
Ok(NonMsg(leftover)) => (Ok(Ready(None)), leftover),
Err(RedisParseErr::Incomplete) => (Ok(NotReady), input),
Err(other_parse_err) => (Err(ManagerErr::RedisParseErr(other_parse_err)), input),
};
// Store leftover in same buffer and set cursor to start after leftover next time
self.cursor = 0;
for byte in &[leftover.as_bytes(), invalid_bytes].concat() {
self.redis_input[self.cursor] = *byte;
self.cursor += 1;
use Async::*;
match self.primary.read(&mut self.input[start..start + BLOCK]) {
Ok(n) => Ok(Ready(n)),
Err(e) if matches!(e.kind(), io::ErrorKind::WouldBlock) => Ok(NotReady),
Err(e) => {
Ready(log::error!("{}", e));
Ok(Ready(0))
}
}
res
}
pub(super) fn update_cache(&mut self, hashtag: String, id: i64) {
@ -116,15 +66,20 @@ impl RedisConn {
self.tag_name_cache.put(id, hashtag);
}
pub(crate) fn send_cmd(&mut self, cmd: RedisCmd, timeline: &Timeline) -> Result<()> {
let namespace = self.redis_namespace.take();
let hashtag = timeline.tag().and_then(|id| self.tag_name_cache.get(&id));
let tl = match &namespace {
Some(ns) => format!("{}:{}", ns, timeline.to_redis_raw_timeline(hashtag)?),
None => timeline.to_redis_raw_timeline(hashtag)?,
};
pub(crate) fn send_cmd(&mut self, cmd: RedisCmd, timelines: &[Timeline]) -> Result<()> {
let namespace = self.namespace.take();
let timelines: Result<Vec<String>> = timelines
.iter()
.map(|tl| {
let hashtag = tl.tag().and_then(|id| self.tag_name_cache.get(&id));
match &namespace {
Some(ns) => Ok(format!("{}:{}", ns, tl.to_redis_raw_timeline(hashtag)?)),
None => Ok(tl.to_redis_raw_timeline(hashtag)?),
}
})
.collect();
let (primary_cmd, secondary_cmd) = cmd.into_sendable(&tl);
let (primary_cmd, secondary_cmd) = cmd.into_sendable(&timelines?[..]);
self.primary.write_all(&primary_cmd)?;
// We also need to set a key to tell the Puma server that we've subscribed or
@ -145,6 +100,7 @@ impl RedisConn {
Self::validate_connection(&mut conn, &addr)?;
conn.set_read_timeout(Some(Duration::from_millis(10)))
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
Self::set_connection_name(&mut conn, &addr)?;
Ok(conn)
}
@ -172,14 +128,27 @@ impl RedisConn {
fn validate_connection(conn: &mut TcpStream, addr: &str) -> Result<()> {
conn.write_all(b"PING\r\n")
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
let mut buffer = vec![0_u8; 7];
conn.read_exact(&mut buffer)
let mut buffer = vec![0_u8; 100];
conn.read(&mut buffer)
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
let reply = String::from_utf8_lossy(&buffer);
match &*reply {
"+PONG\r\n" => Ok(()),
"-NOAUTH" => Err(RedisConnErr::MissingPassword),
"HTTP/1." => Err(RedisConnErr::NotRedis(addr.to_string())),
r if r.starts_with("+PONG\r\n") => Ok(()),
r if r.starts_with("-NOAUTH") => Err(RedisConnErr::MissingPassword),
r if r.starts_with("HTTP/1.") => Err(RedisConnErr::NotRedis(addr.to_string())),
_ => Err(RedisConnErr::InvalidRedisReply(reply.to_string())),
}
}
fn set_connection_name(conn: &mut TcpStream, addr: &str) -> Result<()> {
conn.write_all(b"*3\r\n$6\r\nCLIENT\r\n$7\r\nSETNAME\r\n$8\r\nflodgatt\r\n")
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
let mut buffer = vec![0_u8; 100];
conn.read(&mut buffer)
.map_err(|e| RedisConnErr::with_addr(&addr, e))?;
let reply = String::from_utf8_lossy(&buffer);
match &*reply {
r if r.starts_with("+OK\r\n") => Ok(()),
_ => Err(RedisConnErr::InvalidRedisReply(reply.to_string())),
}
}

2
src/response/redis/connection/err.rs
View File

@ -31,7 +31,7 @@ impl fmt::Display for RedisConnErr {
addr, inner
),
InvalidRedisReply(unexpected_reply) => format!(
"Received and unexpected reply from Redis. Expected `+PONG` reply but got `{}`",
"Received and unexpected reply from Redis: `{}`",
unexpected_reply
),
UnknownRedisErr(io_err) => {

152
src/response/redis/manager.rs
View File

@ -4,8 +4,8 @@
mod err;
pub use err::Error;
use super::Event;
use super::{RedisCmd, RedisConn};
use super::msg::{RedisParseErr, RedisParseOutput};
use super::{Event, RedisCmd, RedisConn};
use crate::config;
use crate::request::{Subscription, Timeline};
@ -13,16 +13,19 @@ pub(self) use super::EventErr;
use futures::Async;
use hashbrown::{HashMap, HashSet};
use std::convert::{TryFrom, TryInto};
use std::str;
use std::sync::{Arc, Mutex, MutexGuard, PoisonError};
use std::time::{Duration, Instant};
use tokio::sync::mpsc::Sender;
type Result<T> = std::result::Result<T, Error>;
type EventChannel = Sender<Arc<Event>>;
/// The item that streams from Redis and is polled by the `ClientAgent`
pub struct Manager {
redis_connection: RedisConn,
timelines: HashMap<Timeline, HashMap<u32, Sender<Arc<Event>>>>,
redis_conn: RedisConn,
timelines: HashMap<Timeline, HashMap<u32, EventChannel>>,
ping_time: Instant,
channel_id: u32,
}
@ -31,7 +34,7 @@ impl Manager {
/// Create a new `Manager`, with its own Redis connections (but no active subscriptions).
pub fn try_from(redis_cfg: &config::Redis) -> Result<Self> {
Ok(Self {
redis_connection: RedisConn::new(redis_cfg)?,
redis_conn: RedisConn::new(redis_cfg)?,
timelines: HashMap::new(),
ping_time: Instant::now(),
channel_id: 0,
@ -42,10 +45,10 @@ impl Manager {
Arc::new(Mutex::new(self))
}
pub fn subscribe(&mut self, subscription: &Subscription, channel: Sender<Arc<Event>>) {
pub fn subscribe(&mut self, subscription: &Subscription, channel: EventChannel) {
let (tag, tl) = (subscription.hashtag_name.clone(), subscription.timeline);
if let (Some(hashtag), Some(id)) = (tag, tl.tag()) {
self.redis_connection.update_cache(hashtag, id);
self.redis_conn.update_cache(hashtag, id);
};
let channels = self.timelines.entry(tl).or_default();
@ -53,67 +56,99 @@ impl Manager {
self.channel_id += 1;
if channels.len() == 1 {
self.redis_connection
.send_cmd(RedisCmd::Subscribe, &tl)
self.redis_conn
.send_cmd(RedisCmd::Subscribe, &[tl])
.unwrap_or_else(|e| log::error!("Could not subscribe to the Redis channel: {}", e));
log::info!("Subscribed to {:?}", tl);
};
}
pub(crate) fn unsubscribe(&mut self, tl: &Timeline) -> Result<()> {
self.redis_connection.send_cmd(RedisCmd::Unsubscribe, &tl)?;
self.timelines.remove(&tl);
Ok(log::info!("Ended stream for {:?}", tl))
fn send_pings(&mut self) -> Result<()> {
// NOTE: this takes two cycles to close a connection after the client times out: on
// the first cycle, this successfully sends the Event to the response::Ws thread but
// that thread fatally errors sending to the client. On the *second* cycle, this
// gets the error. This isn't ideal, but is harmless.
self.ping_time = Instant::now();
let mut subscriptions_to_close = HashSet::new();
self.timelines.retain(|tl, channels| {
channels.retain(|_, chan| try_send_event(Arc::new(Event::Ping), chan, *tl).is_ok());
if channels.is_empty() {
subscriptions_to_close.insert(*tl);
false
} else {
true
}
});
if !subscriptions_to_close.is_empty() {
let timelines: Vec<_> = subscriptions_to_close.into_iter().collect();
&self
.redis_conn
.send_cmd(RedisCmd::Unsubscribe, &timelines[..])?;
log::info!("Unsubscribed from {:?}", timelines);
}
Ok(())
}
pub fn poll_broadcast(&mut self) -> Result<()> {
let mut completed_timelines = HashSet::new();
let log_send_err = |tl, e| Some(log::error!("cannot send to {:?}: {}", tl, e)).is_some();
if self.ping_time.elapsed() > Duration::from_secs(30) {
self.ping_time = Instant::now();
for (tl, channels) in self.timelines.iter_mut() {
channels.retain(|_, chan| match chan.try_send(Arc::new(Event::Ping)) {
Ok(()) => true,
Err(e) if !e.is_closed() => log_send_err(*tl, e),
Err(_) => false,
});
self.send_pings()?
}
// NOTE: this takes two cycles to close a connection after the client
// times out: on the first cycle, this fn sends the Event to the
// response::Ws thread without any error, but that thread encounters an
// error sending to the client and ends. On the *second* cycle, this fn
// gets the error it's waiting on to clean up the connection. This isn't
// ideal, but is harmless, since the only reason we haven't cleaned up the
// connection is that no messages are being sent to that client.
if channels.is_empty() {
completed_timelines.insert(*tl);
}
}
};
let (mut unread_start, mut msg_end) = (0, 0);
loop {
match self.redis_connection.poll_redis() {
Ok(Async::NotReady) => break,
Ok(Async::Ready(Some((tl, event)))) => {
let sendable_event = Arc::new(event);
let channels = self.timelines.get_mut(&tl).ok_or(Error::InvalidId)?;
channels.retain(|_, chan| match chan.try_send(sendable_event.clone()) {
Ok(()) => true,
Err(e) if !e.is_closed() => log_send_err(tl, e),
Err(_) => false,
});
if channels.is_empty() {
completed_timelines.insert(tl);
while let Async::Ready(msg_len) = self.redis_conn.poll_redis(msg_end)? {
msg_end += msg_len;
let input = &self.redis_conn.input[..msg_end];
let mut unread = str::from_utf8(input).unwrap_or_else(|e| {
str::from_utf8(input.split_at(e.valid_up_to()).0).expect("guaranteed by `split_at`")
});
while !unread.is_empty() {
let tag_id_cache = &mut self.redis_conn.tag_id_cache;
let redis_namespace = &self.redis_conn.namespace;
use {Error::InvalidId, RedisParseOutput::*};
unread = match RedisParseOutput::try_from(unread) {
Ok(Msg(msg)) => {
let trimmed_tl = match redis_namespace {
Some(ns) if msg.timeline_txt.starts_with(ns) => {
Some(&msg.timeline_txt[ns.len() + ":timeline:".len()..])
}
None => Some(&msg.timeline_txt["timeline:".len()..]),
Some(_non_matching_ns) => None,
};
if let Some(trimmed_tl) = trimmed_tl {
let tl = Timeline::from_redis_text(trimmed_tl, tag_id_cache)?;
let event: Arc<Event> = Arc::new(msg.event_txt.try_into()?);
let channels = self.timelines.get_mut(&tl).ok_or(InvalidId)?;
channels.retain(|_, c| try_send_event(event.clone(), c, tl).is_ok());
} else {
// skip messages for different Redis namespaces
}
msg.leftover_input
}
Ok(NonMsg(leftover_input)) => leftover_input,
Err(RedisParseErr::Incomplete) => break,
Err(e) => Err(e)?,
};
unread_start = msg_end - unread.len();
}
if !unread.is_empty() && unread_start > unread.len() {
log::info!("Re-using memory");
let (read, unread) = self.redis_conn.input[..msg_end].split_at_mut(unread_start);
for (i, b) in unread.iter().enumerate() {
read[i] = *b;
}
Ok(Async::Ready(None)) => (), // cmd or msg for other namespace
Err(err) => log::error!("{}", err), // drop msg, log err, and proceed
msg_end = unread.len();
unread_start = 0;
}
}
for tl in &mut completed_timelines.iter() {
self.unsubscribe(tl)?;
}
Ok(())
}
@ -146,3 +181,14 @@ impl Manager {
.collect()
}
}
fn try_send_event(event: Arc<Event>, chan: &mut EventChannel, tl: Timeline) -> Result<()> {
match chan.try_send(event) {
Ok(()) => Ok(()),
Err(e) if !e.is_closed() => {
log::error!("cannot send to {:?}: {}", tl, e);
Ok(())
}
Err(e) => Err(e)?,
}
}

18
src/response/redis/manager/err.rs
View File

@ -1,18 +1,18 @@
use super::super::{RedisConnErr, RedisParseErr};
use super::{Event, EventErr};
use crate::request::{Timeline, TimelineErr};
use crate::request::TimelineErr;
use std::fmt;
use std::sync::Arc;
#[derive(Debug)]
pub enum Error {
InvalidId,
TimelineErr(TimelineErr),
EventErr(EventErr),
RedisParseErr(RedisParseErr),
RedisConnErr(RedisConnErr),
ChannelSendErr(tokio::sync::watch::error::SendError<(Timeline, Event)>),
ChannelSendErr2(tokio::sync::mpsc::error::UnboundedTrySendError<Event>),
ChannelSendErr(tokio::sync::mpsc::error::TrySendError<Arc<Event>>),
}
impl std::error::Error for Error {}
@ -30,22 +30,16 @@ impl fmt::Display for Error {
RedisConnErr(inner) => write!(f, "{}", inner),
TimelineErr(inner) => write!(f, "{}", inner),
ChannelSendErr(inner) => write!(f, "{}", inner),
ChannelSendErr2(inner) => write!(f, "{}", inner),
}?;
Ok(())
}
}
impl From<tokio::sync::watch::error::SendError<(Timeline, Event)>> for Error {
fn from(error: tokio::sync::watch::error::SendError<(Timeline, Event)>) -> Self {
impl From<tokio::sync::mpsc::error::TrySendError<Arc<Event>>> for Error {
fn from(error: tokio::sync::mpsc::error::TrySendError<Arc<Event>>) -> Self {
Self::ChannelSendErr(error)
}
}
impl From<tokio::sync::mpsc::error::UnboundedTrySendError<Event>> for Error {
fn from(error: tokio::sync::mpsc::error::UnboundedTrySendError<Event>) -> Self {
Self::ChannelSendErr2(error)
}
}
impl From<EventErr> for Error {
fn from(error: EventErr) -> Self {

5
src/response/redis/msg.rs
View File

@ -82,8 +82,11 @@ fn utf8_to_redis_data<'a>(s: &'a str) -> Result<(RedisData, &'a str), RedisParse
fn after_newline_at(s: &str, start: usize) -> RedisParser<&str> {
let s = s.get(start..).ok_or(Incomplete)?;
if s.len() < 2 {
Err(Incomplete)?;
}
if !s.starts_with("\r\n") {
return Err(RedisParseErr::InvalidLineEnd);
Err(InvalidLineEnd)?;
}
Ok(s.get("\r\n".len()..).ok_or(Incomplete)?)
}