1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401
//! See [super]
use super::super::{
stream_executor::StreamExecutor,
mutiny_stream::MutinyStream,
types::{FullDuplexMultiChannel},
};
use std::{
sync::Arc,
fmt::Debug,
time::Duration,
future::Future,
marker::PhantomData,
};
use indexmap::IndexMap;
use futures::{Stream};
use tokio::{
sync::{RwLock},
};
/// `Multi` is an event handler capable of having several "listeners" -- all of which receives all events.\
/// With this struct, it is possible to:
/// - produce events
/// - spawn new `Stream`s & executors
/// - close `Stream`s (and executors)
/// Example:
/// ```nocompile
/// {reactive_mutiny::Instruments::MetricsWithoutLogs.into()}
pub struct Multi<ItemType: Debug + Sync + Send + 'static,
MultiChannelType: FullDuplexMultiChannel<'static, ItemType, DerivedItemType> + Sync + Send,
const INSTRUMENTS: usize,
DerivedItemType: Debug + Sync + Send + 'static> {
pub multi_name: String,
pub channel: Arc<MultiChannelType>,
pub executor_infos: RwLock<IndexMap<String, ExecutorInfo<INSTRUMENTS>>>,
_phantom: PhantomData<(ItemType, MultiChannelType, DerivedItemType)>,
}
impl<ItemType: Debug + Send + Sync + 'static,
MultiChannelType: FullDuplexMultiChannel<'static, ItemType, DerivedItemType> + Sync + Send + 'static,
const INSTRUMENTS: usize,
DerivedItemType: Debug + Sync + Send + 'static>
Multi<ItemType, MultiChannelType, INSTRUMENTS, DerivedItemType> {
pub fn new<IntoString: Into<String>>(multi_name: IntoString) -> Self {
let multi_name = multi_name.into();
Multi {
multi_name: multi_name.clone(),
channel: MultiChannelType::new(multi_name.clone()),
executor_infos: RwLock::new(IndexMap::new()),
_phantom: PhantomData::default(),
}
}
pub fn stream_name(self: &Self) -> &str {
&self.multi_name
}
#[inline(always)]
#[must_use]
pub fn try_send<F: FnOnce(&mut ItemType)>(&self, setter: F) -> bool {
self.channel.try_send(setter)
}
#[inline(always)]
pub fn send<F: FnOnce(&mut ItemType)>(&self, setter: F) {
self.channel.send(setter);
}
#[inline(always)]
pub fn send_derived(&self, arc_item: &DerivedItemType) {
self.channel.send_derived(arc_item);
}
#[inline(always)]
#[must_use]
pub fn try_send_movable(&self, item: ItemType) -> bool {
self.channel.try_send_movable(item)
}
#[inline(always)]
pub fn buffer_size(&self) -> u32 {
self.channel.buffer_size()
}
#[inline(always)]
pub fn pending_items_count(&self) -> u32 {
self.channel.pending_items_count()
}
/// Spawns a new listener of all subsequent events sent to this `Multi`, processing them through the `Stream` returned by `pipeline_builder()`,
/// which generates events that are Futures & Fallible.
#[must_use]
pub async fn spawn_executor<IntoString: Into<String>,
OutItemType: Send + Debug,
OutStreamType: Stream<Item=OutType> + Send + 'static,
OutType: Future<Output=Result<OutItemType, Box<dyn std::error::Error + Send + Sync>>> + Send,
ErrVoidAsyncType: Future<Output=()> + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(&self,
concurrency_limit: u32,
futures_timeout: Duration,
pipeline_name: IntoString,
pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> OutStreamType,
on_err_callback: impl Fn(Box<dyn std::error::Error + Send + Sync>) -> ErrVoidAsyncType + Send + Sync + 'static,
on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let (in_stream, in_stream_id) = self.channel.create_stream_for_new_events();
let out_stream = pipeline_builder(in_stream);
self.spawn_executor_from_stream(concurrency_limit, futures_timeout, pipeline_name, in_stream_id, out_stream, on_err_callback, on_close_callback).await
}
/// For channels that allow it (like [channels::reference::mmap_log::MmapLog]), spawns two listeners for events sent to this `Multi`:
/// 1) One for past events -- to be processed by the stream returned by `oldies_pipeline_builder()`;
/// 2) Another one for subsequent events -- to be processed by the stream returned by `newies_pipeline_builder()`.
/// By using this method, it is assumed that both pipeline builders returns Futures & Fallible events. If this is not so, see [spawn_non_futures_non_fallible_oldies_executor].\
/// The stream splitting is guaranteed not to drop any events and `sequential_transition` may be used to indicate if old events should be processed first or if both old and new events
/// may be processed simultaneously (in an inevitable out-of-order fashion).
#[must_use]
pub async fn spawn_oldies_executor<IntoString: Into<String>,
OutItemType: Send + Debug,
OldiesOutStreamType: Stream<Item=OutType> + Sync + Send + 'static,
NewiesOutStreamType: Stream<Item=OutType> + Sync + Send + 'static,
OutType: Future<Output=Result<OutItemType, Box<dyn std::error::Error + Send + Sync>>> + Send,
ErrVoidAsyncType: Future<Output=()> + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(self: &Arc<Self>,
concurrency_limit: u32,
sequential_transition: bool,
futures_timeout: Duration,
oldies_pipeline_name: IntoString,
oldies_pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> OldiesOutStreamType,
oldies_on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static,
newies_pipeline_name: IntoString,
newies_pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> NewiesOutStreamType + Send + Sync + 'static,
newies_on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static,
on_err_callback: impl Fn(Box<dyn std::error::Error + Send + Sync>) -> ErrVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let ((oldies_in_stream, oldies_in_stream_id),
(newies_in_stream, newies_in_stream_id)) = self.channel.create_streams_for_old_and_new_events();
let cloned_self = Arc::clone(&self);
let oldies_pipeline_name = oldies_pipeline_name.into();
let newies_pipeline_name = Arc::new(newies_pipeline_name.into());
let on_err_callback_ref1 = Arc::new(on_err_callback);
let on_err_callback_ref2 = Arc::clone(&on_err_callback_ref1);
let oldies_out_stream = oldies_pipeline_builder(oldies_in_stream);
let newies_out_stream = newies_pipeline_builder(newies_in_stream);
match sequential_transition {
true => {
self.spawn_executor_from_stream(concurrency_limit, futures_timeout, oldies_pipeline_name, oldies_in_stream_id, oldies_out_stream,
move |err| on_err_callback_ref1(err),
move |executor| {
let cloned_self = Arc::clone(&cloned_self);
let on_err_callback_ref2 = Arc::clone(&on_err_callback_ref2);
let newies_pipeline_name = Arc::clone(&newies_pipeline_name);
async move {
cloned_self.spawn_executor_from_stream(concurrency_limit, futures_timeout, newies_pipeline_name.as_str(), newies_in_stream_id, newies_out_stream,
move |err| on_err_callback_ref2(err),
move |executor| newies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_oldies_executor(): could not start `newies`/sequential executor: {:?}", err))
.expect("CANNOT SPAWN NEWIES EXECUTOR AFTER OLDIES HAD COMPLETE");
oldies_on_close_callback(executor).await;
}
} ).await
.map_err(|err| format!("Multi::spawn_oldies_executor(): could not start `oldies`/sequential executor: {:?}", err))?;
},
false => {
self.spawn_executor_from_stream(concurrency_limit, futures_timeout, oldies_pipeline_name, oldies_in_stream_id, oldies_out_stream,
move |err| on_err_callback_ref1(err),
move |executor| oldies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_oldies_executor(): could not start `oldies` executor: {:?}", err))?;
self.spawn_executor_from_stream(concurrency_limit, futures_timeout, newies_pipeline_name.as_str(), newies_in_stream_id, newies_out_stream,
move |err| on_err_callback_ref2(err),
move |executor| newies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_oldies_executor(): could not start `newies` executor: {:?}", err))?;
},
}
Ok(())
}
/// Internal method with common code for [spawn_executor()] & [spawn_oldies_executor()].
#[must_use]
async fn spawn_executor_from_stream<IntoString: Into<String>,
OutItemType: Send + Debug,
OutStreamType: Stream<Item=OutType> + Send + 'static,
OutType: Future<Output=Result<OutItemType, Box<dyn std::error::Error + Send + Sync>>> + Send,
ErrVoidAsyncType: Future<Output=()> + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(&self,
concurrency_limit: u32,
futures_timeout: Duration,
pipeline_name: IntoString,
stream_id: u32,
pipelined_stream: OutStreamType,
on_err_callback: impl Fn(Box<dyn std::error::Error + Send + Sync>) -> ErrVoidAsyncType + Send + Sync + 'static,
on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let executor = StreamExecutor::with_futures_timeout(format!("{}: {}", self.stream_name(), pipeline_name.into()), futures_timeout);
self.add_executor(Arc::clone(&executor), stream_id).await?;
executor
.spawn_executor(
concurrency_limit,
on_err_callback,
move |executor| on_close_callback(executor),
pipelined_stream
);
Ok(())
}
/// Spawns a new listener of all subsequent events sent to this `Multi`, processing them through the `Stream` returned by `pipeline_builder()`,
/// which generates events that are Non-Futures & Non-Fallible.
#[must_use]
pub async fn spawn_non_futures_non_fallible_executor<IntoString: Into<String>,
OutItemType: Send + Debug,
OutStreamType: Stream<Item=OutItemType> + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(&self,
concurrency_limit: u32,
pipeline_name: IntoString,
pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> OutStreamType,
on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let (in_stream, in_stream_id) = self.channel.create_stream_for_new_events();
let out_stream = pipeline_builder(in_stream);
self.spawn_non_futures_non_fallible_executor_from_stream(concurrency_limit, pipeline_name, in_stream_id, out_stream, on_close_callback).await
}
/// For channels that allow it (like [channels::reference::mmap_log::MmapLog]), spawns two listeners for events sent to this `Multi`:
/// 1) One for past events -- to be processed by the stream returned by `oldies_pipeline_builder()`;
/// 2) Another one for subsequent events -- to be processed by the stream returned by `newies_pipeline_builder()`.
/// By using this method, it is assumed that both pipeline builders returns non-Futures & non-Fallible events. If this is not so, see [spawn_oldies_executor].\
/// The stream splitting is guaranteed not to drop any events and `sequential_transition` may be used to indicate if old events should be processed first or if both old and new events
/// may be processed simultaneously (in an inevitable out-of-order fashion).
#[must_use]
pub async fn spawn_non_futures_non_fallible_oldies_executor<IntoString: Into<String>,
OutItemType: Send + Debug,
OldiesOutStreamType: Stream<Item=OutItemType> + Sync + Send + 'static,
NewiesOutStreamType: Stream<Item=OutItemType> + Sync + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(self: &Arc<Self>,
concurrency_limit: u32,
sequential_transition: bool,
oldies_pipeline_name: IntoString,
oldies_pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> OldiesOutStreamType,
oldies_on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static,
newies_pipeline_name: IntoString,
newies_pipeline_builder: impl FnOnce(MutinyStream<'static, ItemType, MultiChannelType, DerivedItemType>) -> NewiesOutStreamType,
newies_on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let ((oldies_in_stream, oldies_in_stream_id),
(newies_in_stream, newies_in_stream_id)) = self.channel.create_streams_for_old_and_new_events();
let cloned_self = Arc::clone(&self);
let oldies_pipeline_name = oldies_pipeline_name.into();
let newies_pipeline_name = Arc::new(newies_pipeline_name.into());
let oldies_out_stream = oldies_pipeline_builder(oldies_in_stream);
let newies_out_stream = newies_pipeline_builder(newies_in_stream);
match sequential_transition {
true => {
self.spawn_non_futures_non_fallible_executor_from_stream(concurrency_limit, oldies_pipeline_name, oldies_in_stream_id, oldies_out_stream,
move |executor| {
let cloned_self = Arc::clone(&cloned_self);
let newies_pipeline_name = Arc::clone(&newies_pipeline_name);
async move {
cloned_self.spawn_non_futures_non_fallible_executor_from_stream(concurrency_limit, newies_pipeline_name.as_str(), newies_in_stream_id, newies_out_stream,
move |executor| newies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_non_futures_non_fallible_oldies_executor(): could not start `newies` executor: {:?}", err))
.expect("CANNOT SPAWN NEWIES EXECUTOR AFTER OLDIES HAD COMPLETE");
oldies_on_close_callback(executor).await;
}
}).await
.map_err(|err| format!("Multi::spawn_non_futures_non_fallible_oldies_executor(): could not start `oldies`/sequential executor: {:?}", err))?;
},
false => {
self.spawn_non_futures_non_fallible_executor_from_stream(concurrency_limit, oldies_pipeline_name, oldies_in_stream_id, oldies_out_stream,
move |executor| oldies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_non_futures_non_fallible_oldies_executor(): could not start `oldies` executor: {:?}", err))?;
self.spawn_non_futures_non_fallible_executor_from_stream(concurrency_limit, newies_pipeline_name.as_str(), newies_in_stream_id, newies_out_stream,
move |executor| newies_on_close_callback(executor)).await
.map_err(|err| format!("Multi::spawn_non_futures_non_fallible_oldies_executor(): could not start `newies` executor: {:?}", err))?;
},
}
Ok(())
}
/// Internal method with common code for [spawn_non_futures_non_fallible_executor()] & [spawn_non_futures_non_fallible_oldies_executor()].
#[must_use]
async fn spawn_non_futures_non_fallible_executor_from_stream<IntoString: Into<String>,
OutItemType: Send + Debug,
OutStreamType: Stream<Item=OutItemType> + Send + 'static,
CloseVoidAsyncType: Future<Output=()> + Send + 'static>
(&self,
concurrency_limit: u32,
pipeline_name: IntoString,
stream_id: u32,
pipelined_stream: OutStreamType,
on_close_callback: impl FnOnce(Arc<StreamExecutor<INSTRUMENTS>>) -> CloseVoidAsyncType + Send + Sync + 'static)
-> Result<(), Box<dyn std::error::Error>> {
let executor = StreamExecutor::new(format!("{}: {}", self.stream_name(), pipeline_name.into()));
self.add_executor(Arc::clone(&executor), stream_id).await?;
executor
.spawn_non_futures_non_fallible_executor(
concurrency_limit,
move |executor| on_close_callback(executor),
pipelined_stream
);
Ok(())
}
/// Closes this `Multi`, in isolation -- flushing pending events, closing the producers,
/// waiting for all events to be fully processed and calling all executor's "on close" callbacks.\
/// If this `Multi` share resources with another one (which will get dumped by the "on close"
/// callback), most probably you want to close them atomically -- see [multis_close_async!()]
pub async fn close(self: &Self, timeout: Duration) {
self.channel.gracefully_end_all_streams(timeout).await;
}
/// Asynchronously blocks until all resources associated with the executor responsible for `pipeline_name` are freed:
/// 1) immediately causes `pipeline_name` to cease receiving new elements by removing it from the active list
/// 2) wait for all pending elements to be processed
/// 3) remove the queue/channel and wake the Stream to see that it has ended
/// 4) waits for the executor to inform it ceased its execution
/// 5) return, dropping all resources\
/// Note it might make sense to spawn this operation by a `Tokio task`, for it may block indefinitely if the Stream has no timeout.\
/// Also note that timing out this operation is not advisable, for resources won't be freed until it reaches the last step.\
/// Returns false if there was no executor associated with `pipeline_name`.
pub async fn flush_and_cancel_executor<IntoString: Into<String>>
(self: &Self,
pipeline_name: IntoString,
timeout: Duration) -> bool {
let executor_name = format!("{}: {}", self.multi_name, pipeline_name.into());
// remove the pipeline from the active list
let mut executor_infos = self.executor_infos.write().await;
let executor_info = match executor_infos.remove(&executor_name) {
Some(executor) => executor,
None => return false,
};
drop(executor_infos);
// wait until all elements are taken out from the queue
executor_info.stream_executor.report_scheduled_to_finish();
self.channel.gracefully_end_stream(executor_info.stream_id, timeout).await;
true
}
/// Registers an executor within this `Multi` so it can be managed -- closed, inquired for stats, etc
async fn add_executor(&self, stream_executor: Arc<StreamExecutor<INSTRUMENTS>>, stream_id: u32) -> Result<(), Box<dyn std::error::Error>> {
let mut internal_multis = self.executor_infos.write().await;
if internal_multis.contains_key(&stream_executor.executor_name()) {
Err(Box::from(format!("an executor with the same name is already present: '{}'", stream_executor.executor_name())))
} else {
internal_multis.insert(stream_executor.executor_name(), ExecutorInfo { stream_executor, stream_id });
Ok(())
}
}
}
/// Macro to close, atomically-ish, all [Multi]s passed in as parameters
#[macro_export]
macro_rules! multis_close_async {
($timeout: expr,
$($multi: expr),+) => {
{
tokio::join!( $( $multi.channel.flush($timeout), )+ );
tokio::join!( $( $multi.channel.gracefully_end_all_streams($timeout), )+ );
}
}
}
pub use multis_close_async;
pub use crate::types::ChannelCommon;
/// Keeps track of the `stream_executor` associated to each `stream_id`
pub struct ExecutorInfo<const INSTRUMENTS: usize> {
pub stream_executor: Arc<StreamExecutor<INSTRUMENTS>>,
pub stream_id: u32,
}