Remove concept of ticking, instead wait for jobs

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "background-jobs"
 description = "Background Jobs implemented with actix and futures"
-version = "0.12.0"
+version = "0.13.0"
 license = "AGPL-3.0"
 authors = ["asonix <asonix@asonix.dog>"]
 repository = "https://git.asonix.dog/asonix/background-jobs"
@@ -22,14 +22,17 @@ members = [
 
 [features]
 default = ["background-jobs-actix"]
-completion-logging = ["background-jobs-core/completion-logging", "error-logging"]
+completion-logging = [
+  "background-jobs-core/completion-logging",
+  "error-logging",
+]
 error-logging = ["background-jobs-core/error-logging"]
 
 [dependencies.background-jobs-core]
-version = "0.12.0"
+version = "0.13.0"
 path = "jobs-core"
 
 [dependencies.background-jobs-actix]
-version = "0.12.0"
+version = "0.13.0"
 path = "jobs-actix"
 optional = true

examples/basic-example/Cargo.toml

@@ -9,7 +9,9 @@ edition = "2021"
 [dependencies]
 actix-rt = "2.0.0"
 anyhow = "1.0"
-background-jobs = { version = "0.12.0", path = "../..", features = ["error-logging"] }
+background-jobs = { version = "0.13.0", path = "../..", features = [
+  "error-logging",
+] }
 background-jobs-sled-storage = { version = "0.10.0", path = "../../jobs-sled" }
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["fmt"] }

examples/long-example/Cargo.toml

@@ -9,7 +9,9 @@ edition = "2021"
 [dependencies]
 actix-rt = "2.0.0"
 anyhow = "1.0"
-background-jobs = { version = "0.12.0", path = "../..", features = ["error-logging"] }
+background-jobs = { version = "0.13.0", path = "../..", features = [
+  "error-logging",
+] }
 background-jobs-sled-storage = { version = "0.10.0", path = "../../jobs-sled" }
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["fmt"] }

examples/managed-example/Cargo.toml

@@ -9,7 +9,9 @@ edition = "2021"
 [dependencies]
 actix-rt = "2.0.0"
 anyhow = "1.0"
-background-jobs = { version = "0.12.0", path = "../..", features = ["error-logging"] }
+background-jobs = { version = "0.13.0", path = "../..", features = [
+  "error-logging",
+] }
 background-jobs-sled-storage = { version = "0.10.0", path = "../../jobs-sled" }
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["fmt"] }

examples/managed-example/src/main.rs

@@ -53,12 +53,14 @@ async fn main() -> Result<(), Error> {
         .await?;
 
     // Block on Actix
+    tracing::info!("Press CTRL^C to continue");
     actix_rt::signal::ctrl_c().await?;
 
     // kill the current arbiter
     manager.queue(StopJob).await?;
 
     // Block on Actix
+    tracing::info!("Press CTRL^C to continue");
     actix_rt::signal::ctrl_c().await?;
 
     // See that the workers have respawned
@@ -70,6 +72,7 @@ async fn main() -> Result<(), Error> {
         .await?;
 
     // Block on Actix
+    tracing::info!("Press CTRL^C to quit");
     actix_rt::signal::ctrl_c().await?;
 
     drop(manager);

examples/panic-example/Cargo.toml

@@ -9,7 +9,9 @@ edition = "2021"
 [dependencies]
 actix-rt = "2.0.0"
 anyhow = "1.0"
-background-jobs = { version = "0.12.0", path = "../..", features = ["error-logging"] }
+background-jobs = { version = "0.13.0", path = "../..", features = [
+  "error-logging",
+] }
 background-jobs-sled-storage = { version = "0.10.0", path = "../../jobs-sled" }
 time = "0.3"
 tracing = "0.1"

jobs-actix/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "background-jobs-actix"
 description = "in-process jobs processor based on Actix"
-version = "0.12.0"
+version = "0.13.0"
 license = "AGPL-3.0"
 authors = ["asonix <asonix@asonix.dog>"]
 repository = "https://git.asonix.dog/asonix/background-jobs"
@@ -14,12 +14,18 @@ actix-rt = "2.5.1"
 anyhow = "1.0"
 async-mutex = "1.0.1"
 async-trait = "0.1.24"
-background-jobs-core = { version = "0.12.0", path = "../jobs-core", features = ["with-actix"] }
+background-jobs-core = { version = "0.13.0", path = "../jobs-core", features = [
+  "with-actix",
+] }
 tracing = "0.1"
 tracing-futures = "0.2"
 num_cpus = "1.10.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 thiserror = "1.0"
-tokio = { version = "1", default-features = false, features = ["macros", "rt", "sync"] }
+tokio = { version = "1", default-features = false, features = [
-uuid = { version ="0.8.1", features = ["v4", "serde"] }
+  "macros",
+  "rt",
+  "sync",
+] }
+uuid = { version = "1", features = ["v4", "serde"] }

jobs-actix/src/lib.rs

@@ -171,10 +171,6 @@ impl Manager {
             };
 
             loop {
-                worker_config
-                    .queue_handle
-                    .inner
-                    .ticker(arbiter.handle(), drop_notifier.clone());
                 worker_config.start_managed(&arbiter.handle(), &drop_notifier);
 
                 notifier.notified().await;
@@ -254,20 +250,6 @@ impl Drop for DropNotifier {
     }
 }
 
-/// Create a new Server
-///
-/// In previous versions of this library, the server itself was run on it's own dedicated threads
-/// and guarded access to jobs via messages. Since we now have futures-aware synchronization
-/// primitives, the Server has become an object that gets shared between client threads.
-fn create_server_in_arbiter<S>(arbiter: ArbiterHandle, storage: S) -> QueueHandle
-where
-    S: Storage + Sync + 'static,
-{
-    let handle = create_server_managed(storage);
-    handle.inner.ticker(arbiter, ());
-    handle
-}
-
 /// Create a new managed Server
 ///
 /// In previous versions of this library, the server itself was run on it's own dedicated threads
@@ -361,7 +343,7 @@ where
         storage: S,
         state_fn: impl Fn(QueueHandle) -> State + Send + Sync + 'static,
     ) -> Self {
-        let queue_handle = create_server_in_arbiter(arbiter.clone(), storage);
+        let queue_handle = create_server_managed(storage);
         let q2 = queue_handle.clone();
 
         WorkerConfig {

jobs-actix/src/server.rs

@@ -2,63 +2,10 @@ use crate::{
     storage::{ActixStorage, StorageWrapper},
     worker::Worker,
 };
-use actix_rt::{
-    time::{interval_at, Instant},
-    ArbiterHandle,
-};
 use anyhow::Error;
-use async_mutex::Mutex;
 use background_jobs_core::{NewJobInfo, ReturnJobInfo, Stats, Storage};
-use std::{
+use std::sync::Arc;
-    collections::{HashMap, VecDeque},
+use tracing::{error, trace};
-    sync::Arc,
-    time::Duration,
-};
-use tracing::{error, trace, warn};
-
-type WorkerQueue = VecDeque<Box<dyn Worker + Send + Sync>>;
-
-#[derive(Clone)]
-pub(crate) struct ServerCache {
-    cache: Arc<Mutex<HashMap<String, WorkerQueue>>>,
-}
-
-pub(super) struct Ticker<Extras: Send + 'static> {
-    server: Server,
-    extras: Option<Extras>,
-    arbiter: ArbiterHandle,
-}
-
-impl<Extras: Send + 'static> Drop for Ticker<Extras> {
-    fn drop(&mut self) {
-        let online = self.arbiter.spawn(async move {});
-
-        let extras = self.extras.take().unwrap();
-
-        if online {
-            let server = self.server.clone();
-
-            let arbiter = self.arbiter.clone();
-            let spawned = self.arbiter.spawn(async move {
-                let _ticker = server.ticker(arbiter, extras);
-                let mut interval = interval_at(Instant::now(), Duration::from_secs(1));
-
-                loop {
-                    interval.tick().await;
-                    if let Err(e) = server.check_db().await {
-                        error!("Error while checking database for new jobs, {}", e);
-                    }
-                }
-            });
-
-            if spawned {
-                return;
-            }
-        }
-
-        warn!("Not restarting ticker, arbiter is dead");
-    }
-}
 
 /// The server Actor
 ///
@@ -67,22 +14,9 @@ impl<Extras: Send + 'static> Drop for Ticker<Extras> {
 #[derive(Clone)]
 pub(crate) struct Server {
     storage: Arc<dyn ActixStorage + Send + Sync>,
-    cache: ServerCache,
 }
 
 impl Server {
-    pub(super) fn ticker<Extras: Send + 'static>(
-        &self,
-        arbiter: ArbiterHandle,
-        extras: Extras,
-    ) -> Ticker<Extras> {
-        Ticker {
-            server: self.clone(),
-            extras: Some(extras),
-            arbiter,
-        }
-    }
-
     /// Create a new Server from a compatible storage implementation
     pub(crate) fn new<S>(storage: S) -> Self
     where
@@ -90,26 +24,10 @@ impl Server {
     {
         Server {
             storage: Arc::new(StorageWrapper(storage)),
-            cache: ServerCache::new(),
         }
     }
 
-    async fn check_db(&self) -> Result<(), Error> {
-        trace!("Checking db for ready jobs");
-        for queue in self.cache.keys().await {
-            'worker_loop: while let Some(worker) = self.cache.pop(queue.clone()).await {
-                if !self.try_turning(queue.clone(), worker).await? {
-                    break 'worker_loop;
-                }
-            }
-            trace!("Finished job lookups for queue {}", queue);
-        }
-
-        Ok(())
-    }
-
     pub(crate) async fn new_job(&self, job: NewJobInfo) -> Result<(), Error> {
-        let queue = job.queue().to_owned();
         let ready = job.is_ready();
         self.storage.new_job(job).await?;
 
@@ -118,10 +36,6 @@ impl Server {
             return Ok(());
         }
 
-        if let Some(worker) = self.cache.pop(queue.clone()).await {
-            self.try_turning(queue, worker).await?;
-        }
-
         Ok(())
     }
 
@@ -130,30 +44,17 @@ impl Server {
         worker: Box<dyn Worker + Send + Sync + 'static>,
     ) -> Result<(), Error> {
         trace!("Worker {} requested job", worker.id());
+        let job = self
+            .storage
+            .request_job(worker.queue(), worker.id())
+            .await?;
 
-        self.try_turning(worker.queue().to_owned(), worker).await?;
-
-        Ok(())
-    }
-
-    async fn try_turning(
-        &self,
-        queue: String,
-        worker: Box<dyn Worker + Send + Sync + 'static>,
-    ) -> Result<bool, Error> {
-        trace!("Trying to find job for worker {}", worker.id());
-        if let Ok(Some(job)) = self.storage.request_job(&queue, worker.id()).await {
         if let Err(job) = worker.process(job).await {
             error!("Worker {} has hung up", worker.id());
-                self.storage.return_job(job.unexecuted()).await?
+            self.storage.return_job(job.unexecuted()).await?;
-            }
-        } else {
-            trace!("No job exists, returning worker {}", worker.id());
-            self.cache.push(queue.clone(), worker).await;
-            return Ok(false);
         }
 
-        Ok(true)
+        Ok(())
     }
 
     pub(crate) async fn return_job(&self, job: ReturnJobInfo) -> Result<(), Error> {
@@ -164,37 +65,3 @@ impl Server {
         Ok(self.storage.get_stats().await?)
     }
 }
-
-impl ServerCache {
-    fn new() -> Self {
-        ServerCache {
-            cache: Arc::new(Mutex::new(HashMap::new())),
-        }
-    }
-
-    async fn keys(&self) -> Vec<String> {
-        let cache = self.cache.lock().await;
-
-        cache.keys().cloned().collect()
-    }
-
-    async fn push(&self, queue: String, worker: Box<dyn Worker + Send + Sync>) {
-        let mut cache = self.cache.lock().await;
-
-        let entry = cache.entry(queue).or_insert_with(VecDeque::new);
-        entry.push_back(worker);
-    }
-
-    async fn pop(&self, queue: String) -> Option<Box<dyn Worker + Send + Sync>> {
-        let mut cache = self.cache.lock().await;
-
-        let mut vec_deque = cache.remove(&queue)?;
-        let item = vec_deque.pop_front()?;
-
-        if !vec_deque.is_empty() {
-            cache.insert(queue, vec_deque);
-        }
-
-        Some(item)
-    }
-}

jobs-actix/src/storage.rs

@@ -6,7 +6,7 @@ use uuid::Uuid;
 pub(crate) trait ActixStorage {
     async fn new_job(&self, job: NewJobInfo) -> Result<Uuid, Error>;
 
-    async fn request_job(&self, queue: &str, runner_id: Uuid) -> Result<Option<JobInfo>, Error>;
+    async fn request_job(&self, queue: &str, runner_id: Uuid) -> Result<JobInfo, Error>;
 
     async fn return_job(&self, ret: ReturnJobInfo) -> Result<(), Error>;
 
@@ -28,7 +28,7 @@ where
         Ok(self.0.new_job(job).await?)
     }
 
-    async fn request_job(&self, queue: &str, runner_id: Uuid) -> Result<Option<JobInfo>, Error> {
+    async fn request_job(&self, queue: &str, runner_id: Uuid) -> Result<JobInfo, Error> {
         Ok(self.0.request_job(queue, runner_id).await?)
     }
 

jobs-core/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "background-jobs-core"
 description = "Core types for implementing an asynchronous jobs processor"
-version = "0.12.0"
+version = "0.13.0"
 license = "AGPL-3.0"
 authors = ["asonix <asonix@asonix.dog>"]
 repository = "https://git.asonix.dog/asonix/background-jobs"
@@ -18,12 +18,12 @@ error-logging = []
 [dependencies]
 actix-rt = { version = "2.3.0", optional = true }
 anyhow = "1.0"
-async-mutex = "1.0.1"
 async-trait = "0.1.24"
+event-listener = "2"
 time = { version = "0.3", features = ["serde-human-readable"] }
 tracing = "0.1"
 tracing-futures = "0.2.5"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 thiserror = "1.0"
-uuid = { version = "0.8.1", features = ["serde", "v4"] }
+uuid = { version = "1", features = ["serde", "v4"] }

jobs-core/src/storage.rs

@@ -1,6 +1,6 @@
 use crate::{JobInfo, NewJobInfo, ReturnJobInfo, Stats};
 use std::{error::Error, time::SystemTime};
-use tracing::info;
+use tracing::warn;
 use uuid::Uuid;
 
 /// Define a storage backend for jobs
@@ -29,8 +29,8 @@ pub trait Storage: Clone + Send {
     /// This should fetch a job ready to be processed from the queue
     ///
     /// If a job is not ready, is currently running, or is not in the requested queue, this method
-    /// should not return it. If no jobs meet these criteria, this method should return Ok(None)
+    /// should not return it. If no jobs meet these criteria, this method wait until a job becomes available
-    async fn fetch_job_from_queue(&self, queue: &str) -> Result<Option<JobInfo>, Self::Error>;
+    async fn fetch_job_from_queue(&self, queue: &str) -> Result<JobInfo, Self::Error>;
 
     /// This method tells the storage mechanism to mark the given job as being in the provided
     /// queue
@@ -68,13 +68,10 @@ pub trait Storage: Clone + Send {
     }
 
     /// Fetch a job that is ready to be executed, marking it as running
-    async fn request_job(
+    async fn request_job(&self, queue: &str, runner_id: Uuid) -> Result<JobInfo, Self::Error> {
-        &self,
+        loop {
-        queue: &str,
+            let mut job = self.fetch_job_from_queue(queue).await?;
-        runner_id: Uuid,
+
-    ) -> Result<Option<JobInfo>, Self::Error> {
-        match self.fetch_job_from_queue(queue).await? {
-            Some(mut job) => {
             let now = SystemTime::now();
             if job.is_pending(now) && job.is_ready(now) && job.is_in_queue(queue) {
                 job.run();
@@ -82,18 +79,15 @@ pub trait Storage: Clone + Send {
                 self.save_job(job.clone()).await?;
                 self.update_stats(Stats::run_job).await?;
 
-                    Ok(Some(job))
+                return Ok(job);
             } else {
-                    info!(
+                warn!(
                     "Not fetching job {}, it is not ready for processing",
                     job.id()
                 );
                 self.queue_job(job.queue(), job.id()).await?;
-                    Ok(None)
             }
         }
-            None => Ok(None),
-        }
     }
 
     /// "Return" a job to the database, marking it for retry if needed
@@ -136,54 +130,66 @@ pub trait Storage: Clone + Send {
 /// A default, in-memory implementation of a storage mechanism
 pub mod memory_storage {
     use super::{JobInfo, Stats};
-    use async_mutex::Mutex;
+    use event_listener::Event;
-    use std::{collections::HashMap, convert::Infallible, sync::Arc, time::SystemTime};
+    use std::{
+        collections::HashMap,
+        convert::Infallible,
+        sync::Arc,
+        sync::Mutex,
+        time::{Duration, SystemTime},
+    };
     use uuid::Uuid;
 
-    #[derive(Clone)]
+    /// Allows memory storage to set timeouts for when to retry checking a queue for a job
-    /// An In-Memory store for jobs
+    #[async_trait::async_trait]
-    pub struct Storage {
+    pub trait Timer {
-        inner: Arc<Mutex<Inner>>,
+        /// Race a future against the clock, returning an empty tuple if the clock wins
+        async fn timeout<F>(&self, duration: Duration, future: F) -> Result<F::Output, ()>
+        where
+            F: std::future::Future;
     }
 
     #[derive(Clone)]
+    /// An In-Memory store for jobs
+    pub struct Storage<T> {
+        timer: T,
+        inner: Arc<Mutex<Inner>>,
+    }
+
     struct Inner {
+        queues: HashMap<String, Event>,
         jobs: HashMap<Uuid, JobInfo>,
-        queues: HashMap<Uuid, String>,
+        job_queues: HashMap<Uuid, String>,
         worker_ids: HashMap<Uuid, Uuid>,
         worker_ids_inverse: HashMap<Uuid, Uuid>,
         stats: Stats,
     }
 
-    impl Storage {
+    impl<T: Timer> Storage<T> {
         /// Create a new, empty job store
-        pub fn new() -> Self {
+        pub fn new(timer: T) -> Self {
             Storage {
                 inner: Arc::new(Mutex::new(Inner {
-                    jobs: HashMap::new(),
                     queues: HashMap::new(),
+                    jobs: HashMap::new(),
+                    job_queues: HashMap::new(),
                     worker_ids: HashMap::new(),
                     worker_ids_inverse: HashMap::new(),
                     stats: Stats::default(),
                 })),
+                timer,
             }
         }
     }
 
-    impl Default for Storage {
-        fn default() -> Self {
-            Self::new()
-        }
-    }
-
     #[async_trait::async_trait]
-    impl super::Storage for Storage {
+    impl<T: Timer + Send + Sync + Clone> super::Storage for Storage<T> {
         type Error = Infallible;
 
         async fn generate_id(&self) -> Result<Uuid, Self::Error> {
             let uuid = loop {
                 let uuid = Uuid::new_v4();
-                if !self.inner.lock().await.jobs.contains_key(&uuid) {
+                if !self.inner.lock().unwrap().jobs.contains_key(&uuid) {
                     break uuid;
                 }
             };
@@ -192,25 +198,24 @@ pub mod memory_storage {
         }
 
         async fn save_job(&self, job: JobInfo) -> Result<(), Self::Error> {
-            self.inner.lock().await.jobs.insert(job.id(), job);
+            self.inner.lock().unwrap().jobs.insert(job.id(), job);
 
             Ok(())
         }
 
         async fn fetch_job(&self, id: Uuid) -> Result<Option<JobInfo>, Self::Error> {
-            let j = self.inner.lock().await.jobs.get(&id).cloned();
+            let j = self.inner.lock().unwrap().jobs.get(&id).cloned();
 
             Ok(j)
         }
 
-        async fn fetch_job_from_queue(&self, queue: &str) -> Result<Option<JobInfo>, Self::Error> {
+        async fn fetch_job_from_queue(&self, queue: &str) -> Result<JobInfo, Self::Error> {
-            let mut inner = self.inner.lock().await;
+            loop {
+                let listener = {
+                    let mut inner = self.inner.lock().unwrap();
                     let now = SystemTime::now();
 
-            let j = inner
+                    let j = inner.job_queues.iter().find_map(|(k, v)| {
-                .queues
-                .iter()
-                .filter_map(|(k, v)| {
                         if v == queue {
                             let job = inner.jobs.get(k)?;
 
@@ -220,23 +225,67 @@ pub mod memory_storage {
                         }
 
                         None
-                })
+                    });
-                .next();
 
-            if let Some(ref j) = j {
+                    let duration = if let Some(j) = j {
-                inner.queues.remove(&j.id());
+                        if inner.job_queues.remove(&j.id()).is_some() {
+                            return Ok(j);
+                        } else {
+                            continue;
+                        }
+                    } else {
+                        inner.job_queues.iter().fold(
+                            Duration::from_secs(5),
+                            |duration, (id, v_queue)| {
+                                if v_queue == queue {
+                                    if let Some(job) = inner.jobs.get(id) {
+                                        if let Some(ready_at) = job.next_queue() {
+                                            let job_eta = ready_at
+                                                .duration_since(now)
+                                                .unwrap_or(Duration::from_secs(0));
+
+                                            if job_eta < duration {
+                                                return job_eta;
+                                            }
+                                        }
+                                    }
                                 }
 
-            Ok(j)
+                                duration
+                            },
+                        )
+                    };
+
+                    self.timer.timeout(
+                        duration,
+                        inner
+                            .queues
+                            .entry(queue.to_string())
+                            .or_insert(Event::new())
+                            .listen(),
+                    )
+                };
+
+                let _ = listener.await;
+            }
         }
 
         async fn queue_job(&self, queue: &str, id: Uuid) -> Result<(), Self::Error> {
-            self.inner.lock().await.queues.insert(id, queue.to_owned());
+            let mut inner = self.inner.lock().unwrap();
+
+            inner.job_queues.insert(id, queue.to_owned());
+
+            inner
+                .queues
+                .entry(queue.to_string())
+                .or_insert(Event::new())
+                .notify(1);
+
             Ok(())
         }
 
         async fn run_job(&self, id: Uuid, worker_id: Uuid) -> Result<(), Self::Error> {
-            let mut inner = self.inner.lock().await;
+            let mut inner = self.inner.lock().unwrap();
 
             inner.worker_ids.insert(id, worker_id);
             inner.worker_ids_inverse.insert(worker_id, id);
@@ -244,9 +293,9 @@ pub mod memory_storage {
         }
 
         async fn delete_job(&self, id: Uuid) -> Result<(), Self::Error> {
-            let mut inner = self.inner.lock().await;
+            let mut inner = self.inner.lock().unwrap();
             inner.jobs.remove(&id);
-            inner.queues.remove(&id);
+            inner.job_queues.remove(&id);
             if let Some(worker_id) = inner.worker_ids.remove(&id) {
                 inner.worker_ids_inverse.remove(&worker_id);
             }
@@ -254,14 +303,14 @@ pub mod memory_storage {
         }
 
         async fn get_stats(&self) -> Result<Stats, Self::Error> {
-            Ok(self.inner.lock().await.stats.clone())
+            Ok(self.inner.lock().unwrap().stats.clone())
         }
 
         async fn update_stats<F>(&self, f: F) -> Result<(), Self::Error>
         where
             F: Fn(Stats) -> Stats + Send,
         {
-            let mut inner = self.inner.lock().await;
+            let mut inner = self.inner.lock().unwrap();
 
             inner.stats = (f)(inner.stats.clone());
             Ok(())

jobs-sled/Cargo.toml

@@ -13,10 +13,10 @@ edition = "2021"
 [dependencies]
 actix-rt = "2.0.1"
 async-trait = "0.1.24"
-background-jobs-core = { version = "0.12.0", path = "../jobs-core" }
+background-jobs-core = { version = "0.13.0", path = "../jobs-core" }
 bincode = "1.2"
 sled = "0.34"
 serde_cbor = "0.11"
 thiserror = "1.0"
-tokio = { version = "1", default-features = false, features = ["rt"] }
+tokio = { version = "1", default-features = false, features = ["rt", "sync"] }
-uuid = { version = "0.8.1", features = ["v4", "serde"] }
+uuid = { version = "1", features = ["v4", "serde"] }

jobs-sled/src/lib.rs

@@ -13,10 +13,18 @@
 //! let queue_handle = ServerConfig::new(storage).thread_count(8).start();
 //! ```
 
-use actix_rt::task::{spawn_blocking, JoinError};
+use actix_rt::{
+    task::{spawn_blocking, JoinError},
+    time::timeout,
+};
 use background_jobs_core::{JobInfo, Stats};
 use sled::{Db, Tree};
-use std::time::SystemTime;
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+    time::{Duration, SystemTime},
+};
+use tokio::sync::Notify;
 use uuid::Uuid;
 
 /// The error produced by sled storage calls
@@ -47,7 +55,8 @@ pub struct Storage {
     running_inverse: Tree,
     queue: Tree,
     stats: Tree,
-    db: Db,
+    notifiers: Arc<Mutex<HashMap<String, Arc<Notify>>>>,
+    _db: Db,
 }
 
 #[async_trait::async_trait]
@@ -103,11 +112,13 @@ impl background_jobs_core::Storage for Storage {
         .await??)
     }
 
-    async fn fetch_job_from_queue(&self, queue: &str) -> Result<Option<JobInfo>> {
+    async fn fetch_job_from_queue(&self, queue: &str) -> Result<JobInfo> {
+        loop {
             let this = self.clone();
-        let queue = queue.to_owned();
+            let queue2 = queue.to_owned();
 
-        Ok(spawn_blocking(move || {
+            let job = spawn_blocking(move || {
+                let queue = queue2;
                 let mut job;
 
                 let now = SystemTime::now();
@@ -140,14 +151,62 @@ impl background_jobs_core::Storage for Storage {
 
                 Ok(Some(job)) as Result<Option<JobInfo>>
             })
-        .await??)
+            .await??;
+
+            if let Some(job) = job {
+                return Ok(job);
+            }
+
+            let this = self.clone();
+            let queue2 = queue.to_owned();
+
+            let duration = spawn_blocking(move || {
+                let queue = queue2;
+                let now = SystemTime::now();
+
+                this.queue
+                    .iter()
+                    .filter_map(|res| res.ok())
+                    .filter_map(|(id, in_queue)| {
+                        if queue.as_bytes() == in_queue.as_ref() {
+                            Some(id)
+                        } else {
+                            None
+                        }
+                    })
+                    .filter_map(|id| this.jobinfo.get(id).ok())
+                    .flatten()
+                    .filter_map(|ivec| serde_cbor::from_slice(&ivec).ok())
+                    .filter(|job: &JobInfo| !job.is_ready(now) && job.is_pending(now))
+                    .fold(Duration::from_secs(5), |duration, job| {
+                        if let Some(next_queue) = job.next_queue() {
+                            let job_duration = next_queue
+                                .duration_since(now)
+                                .unwrap_or(Duration::from_secs(0));
+
+                            if job_duration < duration {
+                                return job_duration;
+                            }
+                        }
+
+                        duration
+                    })
+            })
+            .await?;
+
+            let notifier = self.notifier(queue.to_owned());
+
+            let _ = timeout(duration, notifier.notified()).await;
+        }
     }
 
     async fn queue_job(&self, queue: &str, id: Uuid) -> Result<()> {
         let this = self.clone();
-        let queue = queue.to_owned();
+        let queue2 = queue.to_owned();
+
+        spawn_blocking(move || {
+            let queue = queue2;
 
-        Ok(spawn_blocking(move || {
             if let Some(runner_id) = this.running_inverse.remove(id.as_bytes())? {
                 this.running.remove(runner_id)?;
             }
@@ -156,7 +215,11 @@ impl background_jobs_core::Storage for Storage {
 
             Ok(()) as Result<_>
         })
-        .await??)
+        .await??;
+
+        self.notify(queue.to_owned());
+
+        Ok(())
     }
 
     async fn run_job(&self, id: Uuid, runner_id: Uuid) -> Result<()> {
@@ -243,9 +306,28 @@ impl Storage {
             running_inverse: db.open_tree("background-jobs-running-inverse")?,
             queue: db.open_tree("background-jobs-queue")?,
             stats: db.open_tree("background-jobs-stats")?,
-            db,
+            notifiers: Arc::new(Mutex::new(HashMap::new())),
+            _db: db,
         })
     }
+
+    fn notifier(&self, queue: String) -> Arc<Notify> {
+        self.notifiers
+            .lock()
+            .unwrap()
+            .entry(queue)
+            .or_insert_with(|| Arc::new(Notify::new()))
+            .clone()
+    }
+
+    fn notify(&self, queue: String) {
+        self.notifiers
+            .lock()
+            .unwrap()
+            .entry(queue)
+            .or_insert_with(|| Arc::new(Notify::new()))
+            .notify_one();
+    }
 }
 
 impl From<JoinError> for Error {