Asynk change schema (#75)

* add uniq method for AsyncRunnable trait (#70)

* add uniq method for asyncrunnable

* add hash enum

* remove string

* return bool values

* Task struct modified (#71)

* Task struct modified

* asynk module try to adapt new scheme

* delete period in millis

* delete period in millis completed

* Cron support :D

* Cron and single Schedule support :D

* Current timestamp value

* fix bug and new test that confirms that it was a bug

* fix a call

* Update Cargo.toml

Co-authored-by: Ayrat Badykov <ayratin555@gmail.com>

* comments suggestions

* fix clippy

* Better user api for schedule with cron

* Cron tested with example

* Comments adressed

* Comments adressed

Co-authored-by: Ayrat Badykov <ayratin555@gmail.com>

Co-authored-by: Ayrat Badykov <ayratin555@gmail.com>
This commit is contained in:
Pmarquez 2022-08-27 15:58:38 +00:00 committed by GitHub
parent fc935f487e
commit dffee33b9c
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
26 changed files with 462 additions and 545 deletions

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@ -17,6 +17,9 @@ blocking = ["diesel", "diesel-derive-enum", "dotenv"]
asynk = ["bb8-postgres", "postgres-types", "tokio", "async-trait", "typed-builder", "async-recursion"]
[dependencies]
cron = "0.11"
hex = "0.4"
sha2 = "0.10"
chrono = "0.4"
log = "0.4"
serde = "1"

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@ -0,0 +1,12 @@
[package]
name = "simple_async_cron_worker"
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
fang = { path = "../../../" , features = ["asynk"]}
env_logger = "0.9.0"
log = "0.4.0"
tokio = { version = "1", features = ["full"] }

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@ -0,0 +1,33 @@
use fang::async_trait;
use fang::asynk::async_queue::AsyncQueueable;
use fang::asynk::async_runnable::Error;
use fang::asynk::async_runnable::Scheduled;
use fang::serde::{Deserialize, Serialize};
use fang::typetag;
use fang::AsyncRunnable;
#[derive(Serialize, Deserialize)]
#[serde(crate = "fang::serde")]
pub struct MyCronTask {}
#[async_trait]
#[typetag::serde]
impl AsyncRunnable for MyCronTask {
async fn run(&self, _queue: &mut dyn AsyncQueueable) -> Result<(), Error> {
log::info!("CRON!!!!!!!!!!!!!!!",);
Ok(())
}
fn cron(&self) -> Option<Scheduled> {
// sec min hour day of month month day of week year
// be careful works only with UTC hour.
// https://www.timeanddate.com/worldclock/timezone/utc
let expression = "0/20 * * * Aug-Sep * 2022/1";
Some(Scheduled::CronPattern(expression.to_string()))
}
fn uniq(&self) -> bool {
true
}
}

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@ -0,0 +1,41 @@
use fang::asynk::async_queue::AsyncQueue;
use fang::asynk::async_queue::AsyncQueueable;
use fang::asynk::async_worker_pool::AsyncWorkerPool;
use fang::AsyncRunnable;
use fang::NoTls;
use simple_async_cron_worker::MyCronTask;
use std::time::Duration;
#[tokio::main]
async fn main() {
env_logger::init();
log::info!("Starting...");
let max_pool_size: u32 = 3;
let mut queue = AsyncQueue::builder()
.uri("postgres://postgres:postgres@localhost/fang")
.max_pool_size(max_pool_size)
.build();
queue.connect(NoTls).await.unwrap();
log::info!("Queue connected...");
let mut pool: AsyncWorkerPool<AsyncQueue<NoTls>> = AsyncWorkerPool::builder()
.number_of_workers(10_u32)
.queue(queue.clone())
.build();
log::info!("Pool created ...");
pool.start().await;
log::info!("Workers started ...");
let task = MyCronTask {};
queue
.schedule_task(&task as &dyn AsyncRunnable)
.await
.unwrap();
tokio::time::sleep(Duration::from_secs(100)).await;
}

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@ -6,7 +6,7 @@ edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
fang = { path = "../../" , features = ["asynk"]}
fang = { path = "../../../" , features = ["asynk"]}
env_logger = "0.9.0"
log = "0.4.0"
tokio = { version = "1", features = ["full"] }

View file

@ -12,11 +12,10 @@ async fn main() {
env_logger::init();
log::info!("Starting...");
let max_pool_size: u32 = 2;
let max_pool_size: u32 = 3;
let mut queue = AsyncQueue::builder()
.uri("postgres://postgres:postgres@localhost/fang")
.max_pool_size(max_pool_size)
.duplicated_tasks(true)
.build();
queue.connect(NoTls).await.unwrap();
@ -40,6 +39,7 @@ async fn main() {
.insert_task(&task1 as &dyn AsyncRunnable)
.await
.unwrap();
queue
.insert_task(&task2 as &dyn AsyncRunnable)
.await

View file

@ -8,7 +8,6 @@ CREATE TABLE fang_tasks (
error_message TEXT,
state fang_task_state DEFAULT 'new' NOT NULL,
task_type VARCHAR DEFAULT 'common' NOT NULL,
periodic BOOLEAN DEFAULT FALSE,
uniq_hash CHAR(64),
scheduled_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),

View file

@ -1,3 +1,4 @@
use crate::async_runnable::Scheduled::*;
use crate::asynk::async_runnable::AsyncRunnable;
use crate::asynk::async_runnable::Error as FangError;
use async_trait::async_trait;
@ -9,10 +10,11 @@ use bb8_postgres::tokio_postgres::Socket;
use bb8_postgres::tokio_postgres::Transaction;
use bb8_postgres::PostgresConnectionManager;
use chrono::DateTime;
use chrono::Duration;
use chrono::Utc;
use cron::Schedule;
use postgres_types::{FromSql, ToSql};
use std::time::Duration as StdDuration;
use sha2::{Digest, Sha256};
use std::str::FromStr;
use thiserror::Error;
use typed_builder::TypedBuilder;
use uuid::Uuid;
@ -21,21 +23,15 @@ use uuid::Uuid;
use bb8_postgres::tokio_postgres::tls::NoTls;
const INSERT_TASK_QUERY: &str = include_str!("queries/insert_task.sql");
const INSERT_PERIODIC_TASK_QUERY: &str = include_str!("queries/insert_periodic_task.sql");
const SCHEDULE_NEXT_TASK_QUERY: &str = include_str!("queries/schedule_next_task.sql");
const INSERT_TASK_UNIQ_QUERY: &str = include_str!("queries/insert_task_uniq.sql");
const UPDATE_TASK_STATE_QUERY: &str = include_str!("queries/update_task_state.sql");
const FAIL_TASK_QUERY: &str = include_str!("queries/fail_task.sql");
const REMOVE_ALL_TASK_QUERY: &str = include_str!("queries/remove_all_tasks.sql");
const REMOVE_TASK_QUERY: &str = include_str!("queries/remove_task.sql");
const REMOVE_TASKS_TYPE_QUERY: &str = include_str!("queries/remove_tasks_type.sql");
const FETCH_TASK_TYPE_QUERY: &str = include_str!("queries/fetch_task_type.sql");
const FETCH_PERIODIC_TASKS_QUERY: &str = include_str!("queries/fetch_periodic_tasks.sql");
const FIND_TASK_BY_METADATA_QUERY: &str = include_str!("queries/find_task_by_metadata.sql");
#[cfg(test)]
const FIND_TASK_BY_UNIQ_HASH_QUERY: &str = include_str!("queries/find_task_by_uniq_hash.sql");
const FIND_TASK_BY_ID_QUERY: &str = include_str!("queries/find_task_by_id.sql");
#[cfg(test)]
const FIND_PERIODIC_TASK_BY_ID_QUERY: &str = include_str!("queries/find_periodic_task_by_id.sql");
pub const DEFAULT_TASK_TYPE: &str = "common";
@ -71,25 +67,23 @@ pub struct Task {
#[builder(setter(into))]
pub task_type: String,
#[builder(setter(into))]
pub uniq_hash: Option<String>,
#[builder(setter(into))]
pub scheduled_at: DateTime<Utc>,
#[builder(setter(into))]
pub created_at: DateTime<Utc>,
#[builder(setter(into))]
pub updated_at: DateTime<Utc>,
}
#[derive(TypedBuilder, Debug, Eq, PartialEq, Clone)]
pub struct PeriodicTask {
#[builder(setter(into))]
pub id: Uuid,
#[builder(setter(into))]
pub metadata: serde_json::Value,
#[builder(setter(into))]
pub period_in_millis: i64,
#[builder(setter(into))]
pub scheduled_at: Option<DateTime<Utc>>,
#[builder(setter(into))]
pub created_at: DateTime<Utc>,
#[builder(setter(into))]
pub updated_at: DateTime<Utc>,
#[derive(Debug, Error)]
pub enum CronError {
#[error(transparent)]
LibraryError(#[from] cron::error::Error),
#[error("You have to implement method `cron()` in your AsyncRunnable")]
TaskNotSchedulableError,
#[error("No timestamps match with this cron pattern")]
NoTimestampsError,
}
#[derive(Debug, Error)]
@ -100,6 +94,8 @@ pub enum AsyncQueueError {
PgError(#[from] bb8_postgres::tokio_postgres::Error),
#[error(transparent)]
SerdeError(#[from] serde_json::Error),
#[error(transparent)]
CronError(#[from] CronError),
#[error("returned invalid result (expected {expected:?}, found {found:?})")]
ResultError { expected: u64, found: u64 },
#[error(
@ -110,6 +106,12 @@ pub enum AsyncQueueError {
TimeError,
}
impl From<cron::error::Error> for AsyncQueueError {
fn from(error: cron::error::Error) -> Self {
AsyncQueueError::CronError(CronError::LibraryError(error))
}
}
impl From<AsyncQueueError> for FangError {
fn from(error: AsyncQueueError) -> Self {
let message = format!("{:?}", error);
@ -127,12 +129,15 @@ pub trait AsyncQueueable: Send {
) -> Result<Option<Task>, AsyncQueueError>;
async fn insert_task(&mut self, task: &dyn AsyncRunnable) -> Result<Task, AsyncQueueError>;
async fn remove_all_tasks(&mut self) -> Result<u64, AsyncQueueError>;
async fn remove_task(&mut self, task: Task) -> Result<u64, AsyncQueueError>;
async fn remove_tasks_type(&mut self, task_type: &str) -> Result<u64, AsyncQueueError>;
async fn find_task_by_id(&mut self, id: Uuid) -> Result<Task, AsyncQueueError>;
async fn update_task_state(
&mut self,
task: Task,
@ -142,22 +147,7 @@ pub trait AsyncQueueable: Send {
async fn fail_task(&mut self, task: Task, error_message: &str)
-> Result<Task, AsyncQueueError>;
async fn fetch_periodic_tasks(
&mut self,
error_margin: StdDuration,
) -> Result<Option<Vec<PeriodicTask>>, AsyncQueueError>;
async fn insert_periodic_task(
&mut self,
task: &dyn AsyncRunnable,
timestamp: DateTime<Utc>,
period: i64,
) -> Result<PeriodicTask, AsyncQueueError>;
async fn schedule_next_task(
&mut self,
periodic_task: PeriodicTask,
) -> Result<PeriodicTask, AsyncQueueError>;
async fn schedule_task(&mut self, task: &dyn AsyncRunnable) -> Result<Task, AsyncQueueError>;
}
#[derive(TypedBuilder, Debug, Clone)]
@ -174,8 +164,6 @@ where
uri: String,
#[builder(setter(into))]
max_pool_size: u32,
#[builder(default = false, setter(into))]
duplicated_tasks: bool,
#[builder(default = false, setter(skip))]
connected: bool,
}
@ -185,47 +173,24 @@ where
pub struct AsyncQueueTest<'a> {
#[builder(setter(into))]
pub transaction: Transaction<'a>,
#[builder(default = false, setter(into))]
pub duplicated_tasks: bool,
}
#[cfg(test)]
impl<'a> AsyncQueueTest<'a> {
pub async fn find_task_by_id(&mut self, id: Uuid) -> Result<Task, AsyncQueueError> {
let row: Row = self
.transaction
.query_one(FIND_TASK_BY_ID_QUERY, &[&id])
.await?;
let task = AsyncQueue::<NoTls>::row_to_task(row);
Ok(task)
}
pub async fn find_periodic_task_by_id(
&mut self,
id: Uuid,
) -> Result<PeriodicTask, AsyncQueueError> {
let row: Row = self
.transaction
.query_one(FIND_PERIODIC_TASK_BY_ID_QUERY, &[&id])
.await?;
let task = AsyncQueue::<NoTls>::row_to_periodic_task(row);
Ok(task)
}
}
#[cfg(test)]
#[async_trait]
impl AsyncQueueable for AsyncQueueTest<'_> {
async fn find_task_by_id(&mut self, id: Uuid) -> Result<Task, AsyncQueueError> {
let transaction = &mut self.transaction;
AsyncQueue::<NoTls>::find_task_by_id_query(transaction, id).await
}
async fn fetch_and_touch_task(
&mut self,
task_type: Option<String>,
) -> Result<Option<Task>, AsyncQueueError> {
let transaction = &mut self.transaction;
let task = AsyncQueue::<NoTls>::fetch_and_touch_task_query(transaction, task_type).await?;
Ok(task)
AsyncQueue::<NoTls>::fetch_and_touch_task_query(transaction, task_type).await
}
async fn insert_task(&mut self, task: &dyn AsyncRunnable) -> Result<Task, AsyncQueueError> {
@ -233,84 +198,86 @@ impl AsyncQueueable for AsyncQueueTest<'_> {
let metadata = serde_json::to_value(task)?;
let task: Task = if self.duplicated_tasks {
AsyncQueue::<NoTls>::insert_task_query(transaction, metadata, &task.task_type()).await?
let task: Task = if !task.uniq() {
AsyncQueue::<NoTls>::insert_task_query(
transaction,
metadata,
&task.task_type(),
Utc::now(),
)
.await?
} else {
AsyncQueue::<NoTls>::insert_task_if_not_exist_query(
transaction,
metadata,
&task.task_type(),
Utc::now(),
)
.await?
};
Ok(task)
}
async fn schedule_next_task(
&mut self,
periodic_task: PeriodicTask,
) -> Result<PeriodicTask, AsyncQueueError> {
let transaction = &mut self.transaction;
let periodic_task =
AsyncQueue::<NoTls>::schedule_next_task_query(transaction, periodic_task).await?;
Ok(periodic_task)
}
async fn insert_periodic_task(
&mut self,
task: &dyn AsyncRunnable,
timestamp: DateTime<Utc>,
period: i64,
) -> Result<PeriodicTask, AsyncQueueError> {
async fn schedule_task(&mut self, task: &dyn AsyncRunnable) -> Result<Task, AsyncQueueError> {
let transaction = &mut self.transaction;
let metadata = serde_json::to_value(task)?;
let periodic_task = AsyncQueue::<NoTls>::insert_periodic_task_query(
let scheduled_at = match task.cron() {
Some(scheduled) => match scheduled {
CronPattern(cron_pattern) => {
let schedule = Schedule::from_str(&cron_pattern)?;
let mut iterator = schedule.upcoming(Utc);
iterator
.next()
.ok_or(AsyncQueueError::CronError(CronError::NoTimestampsError))?
}
ScheduleOnce(datetime) => datetime,
},
None => {
return Err(AsyncQueueError::CronError(
CronError::TaskNotSchedulableError,
));
}
};
let task: Task = if !task.uniq() {
AsyncQueue::<NoTls>::insert_task_query(
transaction,
metadata,
timestamp,
period,
&task.task_type(),
scheduled_at,
)
.await?;
.await?
} else {
AsyncQueue::<NoTls>::insert_task_if_not_exist_query(
transaction,
metadata,
&task.task_type(),
scheduled_at,
)
.await?
};
Ok(periodic_task)
}
async fn fetch_periodic_tasks(
&mut self,
error_margin: StdDuration,
) -> Result<Option<Vec<PeriodicTask>>, AsyncQueueError> {
let transaction = &mut self.transaction;
let periodic_task =
AsyncQueue::<NoTls>::fetch_periodic_tasks_query(transaction, error_margin).await?;
Ok(periodic_task)
Ok(task)
}
async fn remove_all_tasks(&mut self) -> Result<u64, AsyncQueueError> {
let transaction = &mut self.transaction;
let result = AsyncQueue::<NoTls>::remove_all_tasks_query(transaction).await?;
Ok(result)
AsyncQueue::<NoTls>::remove_all_tasks_query(transaction).await
}
async fn remove_task(&mut self, task: Task) -> Result<u64, AsyncQueueError> {
let transaction = &mut self.transaction;
let result = AsyncQueue::<NoTls>::remove_task_query(transaction, task).await?;
Ok(result)
AsyncQueue::<NoTls>::remove_task_query(transaction, task).await
}
async fn remove_tasks_type(&mut self, task_type: &str) -> Result<u64, AsyncQueueError> {
let transaction = &mut self.transaction;
let result = AsyncQueue::<NoTls>::remove_tasks_type_query(transaction, task_type).await?;
Ok(result)
AsyncQueue::<NoTls>::remove_tasks_type_query(transaction, task_type).await
}
async fn update_task_state(
@ -320,9 +287,7 @@ impl AsyncQueueable for AsyncQueueTest<'_> {
) -> Result<Task, AsyncQueueError> {
let transaction = &mut self.transaction;
let task = AsyncQueue::<NoTls>::update_task_state_query(transaction, task, state).await?;
Ok(task)
AsyncQueue::<NoTls>::update_task_state_query(transaction, task, state).await
}
async fn fail_task(
@ -332,9 +297,7 @@ impl AsyncQueueable for AsyncQueueTest<'_> {
) -> Result<Task, AsyncQueueError> {
let transaction = &mut self.transaction;
let task = AsyncQueue::<NoTls>::fail_task_query(transaction, task, error_message).await?;
Ok(task)
AsyncQueue::<NoTls>::fail_task_query(transaction, task, error_message).await
}
}
@ -384,6 +347,16 @@ where
Self::execute_query(transaction, REMOVE_TASKS_TYPE_QUERY, &[&task_type], None).await
}
async fn find_task_by_id_query(
transaction: &mut Transaction<'_>,
id: Uuid,
) -> Result<Task, AsyncQueueError> {
let row: Row = transaction.query_one(FIND_TASK_BY_ID_QUERY, &[&id]).await?;
let task = Self::row_to_task(row);
Ok(task)
}
async fn fail_task_query(
transaction: &mut Transaction<'_>,
task: Task,
@ -435,7 +408,7 @@ where
task_type: &str,
) -> Result<Task, AsyncQueueError> {
let row: Row = transaction
.query_one(FETCH_TASK_TYPE_QUERY, &[&task_type])
.query_one(FETCH_TASK_TYPE_QUERY, &[&task_type, &Utc::now()])
.await?;
let task = Self::row_to_task(row);
@ -461,72 +434,32 @@ where
transaction: &mut Transaction<'_>,
metadata: serde_json::Value,
task_type: &str,
scheduled_at: DateTime<Utc>,
) -> Result<Task, AsyncQueueError> {
let row: Row = transaction
.query_one(INSERT_TASK_QUERY, &[&metadata, &task_type])
.query_one(INSERT_TASK_QUERY, &[&metadata, &task_type, &scheduled_at])
.await?;
let task = Self::row_to_task(row);
Ok(task)
}
async fn schedule_next_task_query(
transaction: &mut Transaction<'_>,
periodic_task: PeriodicTask,
) -> Result<PeriodicTask, AsyncQueueError> {
let updated_at = Utc::now();
let scheduled_at = updated_at + Duration::milliseconds(periodic_task.period_in_millis);
let row: Row = transaction
.query_one(SCHEDULE_NEXT_TASK_QUERY, &[&scheduled_at, &updated_at])
.await?;
let periodic_task = Self::row_to_periodic_task(row);
Ok(periodic_task)
}
async fn insert_periodic_task_query(
async fn insert_task_uniq_query(
transaction: &mut Transaction<'_>,
metadata: serde_json::Value,
timestamp: DateTime<Utc>,
period: i64,
) -> Result<PeriodicTask, AsyncQueueError> {
task_type: &str,
scheduled_at: DateTime<Utc>,
) -> Result<Task, AsyncQueueError> {
let uniq_hash = Self::calculate_hash(metadata.to_string());
let row: Row = transaction
.query_one(
INSERT_PERIODIC_TASK_QUERY,
&[&metadata, &timestamp, &period],
INSERT_TASK_UNIQ_QUERY,
&[&metadata, &task_type, &uniq_hash, &scheduled_at],
)
.await?;
let periodic_task = Self::row_to_periodic_task(row);
Ok(periodic_task)
}
async fn fetch_periodic_tasks_query(
transaction: &mut Transaction<'_>,
error_margin: StdDuration,
) -> Result<Option<Vec<PeriodicTask>>, AsyncQueueError> {
let current_time = Utc::now();
let margin: Duration = match Duration::from_std(error_margin) {
Ok(value) => Ok(value),
Err(_) => Err(AsyncQueueError::TimeError),
}?;
let low_limit = current_time - margin;
let high_limit = current_time + margin;
let rows: Vec<Row> = transaction
.query(FETCH_PERIODIC_TASKS_QUERY, &[&low_limit, &high_limit])
.await?;
let periodic_tasks: Vec<PeriodicTask> = rows
.into_iter()
.map(|row| Self::row_to_periodic_task(row))
.collect();
if periodic_tasks.is_empty() {
Ok(None)
} else {
Ok(Some(periodic_tasks))
}
let task = Self::row_to_task(row);
Ok(task)
}
async fn execute_query(
@ -552,19 +485,31 @@ where
transaction: &mut Transaction<'_>,
metadata: serde_json::Value,
task_type: &str,
scheduled_at: DateTime<Utc>,
) -> Result<Task, AsyncQueueError> {
match Self::find_task_by_metadata_query(transaction, &metadata).await {
match Self::find_task_by_uniq_hash_query(transaction, &metadata).await {
Some(task) => Ok(task),
None => Self::insert_task_query(transaction, metadata, task_type).await,
None => {
Self::insert_task_uniq_query(transaction, metadata, task_type, scheduled_at).await
}
}
}
async fn find_task_by_metadata_query(
fn calculate_hash(json: String) -> String {
let mut hasher = Sha256::new();
hasher.update(json.as_bytes());
let result = hasher.finalize();
hex::encode(result)
}
async fn find_task_by_uniq_hash_query(
transaction: &mut Transaction<'_>,
metadata: &serde_json::Value,
) -> Option<Task> {
let uniq_hash = Self::calculate_hash(metadata.to_string());
let result = transaction
.query_one(FIND_TASK_BY_METADATA_QUERY, &[metadata])
.query_one(FIND_TASK_BY_UNIQ_HASH_QUERY, &[&uniq_hash])
.await;
match result {
@ -573,47 +518,29 @@ where
}
}
fn row_to_periodic_task(row: Row) -> PeriodicTask {
let id: Uuid = row.get("id");
let metadata: serde_json::Value = row.get("metadata");
let period_in_millis: i64 = row.get("period_in_millis");
let scheduled_at: Option<DateTime<Utc>> = match row.try_get("scheduled_at") {
Ok(datetime) => Some(datetime),
Err(_) => None,
};
let created_at: DateTime<Utc> = row.get("created_at");
let updated_at: DateTime<Utc> = row.get("updated_at");
PeriodicTask::builder()
.id(id)
.metadata(metadata)
.period_in_millis(period_in_millis)
.scheduled_at(scheduled_at)
.created_at(created_at)
.updated_at(updated_at)
.build()
}
fn row_to_task(row: Row) -> Task {
let id: Uuid = row.get("id");
let metadata: serde_json::Value = row.get("metadata");
let error_message: Option<String> = match row.try_get("error_message") {
Ok(error_message) => Some(error_message),
Err(_) => None,
};
let error_message: Option<String> = row.try_get("error_message").ok();
let uniq_hash: Option<String> = row.try_get("uniq_hash").ok();
let state: FangTaskState = row.get("state");
let task_type: String = row.get("task_type");
let created_at: DateTime<Utc> = row.get("created_at");
let updated_at: DateTime<Utc> = row.get("updated_at");
let scheduled_at: DateTime<Utc> = row.get("scheduled_at");
Task::builder()
.id(id)
.metadata(metadata)
.error_message(error_message)
.state(state)
.uniq_hash(uniq_hash)
.task_type(task_type)
.created_at(created_at)
.updated_at(updated_at)
.scheduled_at(scheduled_at)
.build()
}
}
@ -626,6 +553,17 @@ where
<Tls as MakeTlsConnect<Socket>>::TlsConnect: Send,
<<Tls as MakeTlsConnect<Socket>>::TlsConnect as TlsConnect<Socket>>::Future: Send,
{
async fn find_task_by_id(&mut self, id: Uuid) -> Result<Task, AsyncQueueError> {
let mut connection = self.pool.as_ref().unwrap().get().await?;
let mut transaction = connection.transaction().await?;
let task = Self::find_task_by_id_query(&mut transaction, id).await?;
transaction.commit().await?;
Ok(task)
}
async fn fetch_and_touch_task(
&mut self,
task_type: Option<String>,
@ -648,10 +586,16 @@ where
let metadata = serde_json::to_value(task)?;
let task: Task = if self.duplicated_tasks {
Self::insert_task_query(&mut transaction, metadata, &task.task_type()).await?
let task: Task = if !task.uniq() {
Self::insert_task_query(&mut transaction, metadata, &task.task_type(), Utc::now())
.await?
} else {
Self::insert_task_if_not_exist_query(&mut transaction, metadata, &task.task_type())
Self::insert_task_if_not_exist_query(
&mut transaction,
metadata,
&task.task_type(),
Utc::now(),
)
.await?
};
@ -660,55 +604,44 @@ where
Ok(task)
}
async fn insert_periodic_task(
&mut self,
task: &dyn AsyncRunnable,
timestamp: DateTime<Utc>,
period: i64,
) -> Result<PeriodicTask, AsyncQueueError> {
async fn schedule_task(&mut self, task: &dyn AsyncRunnable) -> Result<Task, AsyncQueueError> {
self.check_if_connection()?;
let mut connection = self.pool.as_ref().unwrap().get().await?;
let mut transaction = connection.transaction().await?;
let metadata = serde_json::to_value(task)?;
let periodic_task =
Self::insert_periodic_task_query(&mut transaction, metadata, timestamp, period).await?;
transaction.commit().await?;
Ok(periodic_task)
let scheduled_at = match task.cron() {
Some(scheduled) => match scheduled {
CronPattern(cron_pattern) => {
let schedule = Schedule::from_str(&cron_pattern)?;
let mut iterator = schedule.upcoming(Utc);
iterator
.next()
.ok_or(AsyncQueueError::CronError(CronError::NoTimestampsError))?
}
async fn schedule_next_task(
&mut self,
periodic_task: PeriodicTask,
) -> Result<PeriodicTask, AsyncQueueError> {
self.check_if_connection()?;
let mut connection = self.pool.as_ref().unwrap().get().await?;
let mut transaction = connection.transaction().await?;
let periodic_task = Self::schedule_next_task_query(&mut transaction, periodic_task).await?;
transaction.commit().await?;
Ok(periodic_task)
ScheduleOnce(datetime) => datetime,
},
None => {
return Err(AsyncQueueError::CronError(
CronError::TaskNotSchedulableError,
));
}
};
async fn fetch_periodic_tasks(
&mut self,
error_margin: StdDuration,
) -> Result<Option<Vec<PeriodicTask>>, AsyncQueueError> {
self.check_if_connection()?;
let mut connection = self.pool.as_ref().unwrap().get().await?;
let mut transaction = connection.transaction().await?;
let periodic_task =
Self::fetch_periodic_tasks_query(&mut transaction, error_margin).await?;
let task: Task = if !task.uniq() {
Self::insert_task_query(&mut transaction, metadata, &task.task_type(), scheduled_at)
.await?
} else {
Self::insert_task_if_not_exist_query(
&mut transaction,
metadata,
&task.task_type(),
scheduled_at,
)
.await?
};
transaction.commit().await?;
Ok(periodic_task)
Ok(task)
}
async fn remove_all_tasks(&mut self) -> Result<u64, AsyncQueueError> {
@ -784,12 +717,17 @@ mod async_queue_tests {
use super::AsyncQueueable;
use super::FangTaskState;
use super::Task;
use crate::async_runnable::Scheduled;
use crate::asynk::AsyncError as Error;
use crate::asynk::AsyncRunnable;
use async_trait::async_trait;
use bb8_postgres::bb8::Pool;
use bb8_postgres::tokio_postgres::NoTls;
use bb8_postgres::PostgresConnectionManager;
use chrono::DateTime;
use chrono::Duration;
use chrono::SubsecRound;
use chrono::Utc;
use serde::{Deserialize, Serialize};
#[derive(Serialize, Deserialize)]
@ -805,6 +743,25 @@ mod async_queue_tests {
}
}
#[derive(Serialize, Deserialize)]
struct AsyncTaskSchedule {
pub number: u16,
pub datetime: String,
}
#[typetag::serde]
#[async_trait]
impl AsyncRunnable for AsyncTaskSchedule {
async fn run(&self, _queueable: &mut dyn AsyncQueueable) -> Result<(), Error> {
Ok(())
}
fn cron(&self) -> Option<Scheduled> {
let datetime = self.datetime.parse::<DateTime<Utc>>().ok()?;
Some(Scheduled::ScheduleOnce(datetime))
}
}
#[tokio::test]
async fn insert_task_creates_new_task() {
let pool = pool().await;
@ -912,6 +869,32 @@ mod async_queue_tests {
test.transaction.rollback().await.unwrap();
}
#[tokio::test]
async fn schedule_task_test() {
let pool = pool().await;
let mut connection = pool.get().await.unwrap();
let transaction = connection.transaction().await.unwrap();
let mut test = AsyncQueueTest::builder().transaction(transaction).build();
let datetime = (Utc::now() + Duration::seconds(7)).round_subsecs(0);
let task = &AsyncTaskSchedule {
number: 1,
datetime: datetime.to_string(),
};
let task = test.schedule_task(task).await.unwrap();
let metadata = task.metadata.as_object().unwrap();
let number = metadata["number"].as_u64();
let type_task = metadata["type"].as_str();
assert_eq!(Some(1), number);
assert_eq!(Some("AsyncTaskSchedule"), type_task);
assert_eq!(task.scheduled_at, datetime);
}
#[tokio::test]
async fn fetch_and_touch_test() {
let pool = pool().await;

View file

@ -1,5 +1,7 @@
use crate::asynk::async_queue::AsyncQueueable;
use async_trait::async_trait;
use chrono::DateTime;
use chrono::Utc;
const COMMON_TYPE: &str = "common";
@ -8,6 +10,11 @@ pub struct Error {
pub description: String,
}
pub enum Scheduled {
CronPattern(String),
ScheduleOnce(DateTime<Utc>),
}
#[typetag::serde(tag = "type")]
#[async_trait]
pub trait AsyncRunnable: Send + Sync {
@ -16,4 +23,12 @@ pub trait AsyncRunnable: Send + Sync {
fn task_type(&self) -> String {
COMMON_TYPE.to_string()
}
fn uniq(&self) -> bool {
false
}
fn cron(&self) -> Option<Scheduled> {
None
}
}

View file

@ -1,260 +0,0 @@
use crate::asynk::async_queue::AsyncQueueable;
use crate::asynk::async_queue::PeriodicTask;
use crate::asynk::AsyncError as Error;
use crate::asynk::AsyncRunnable;
use async_recursion::async_recursion;
use log::error;
use std::time::Duration;
use tokio::task::JoinHandle;
use tokio::time::sleep;
use typed_builder::TypedBuilder;
#[derive(TypedBuilder, Clone)]
pub struct Scheduler<AQueue>
where
AQueue: AsyncQueueable + Clone + Sync + 'static,
{
#[builder(setter(into))]
pub check_period: Duration,
#[builder(setter(into))]
pub error_margin: Duration,
#[builder(setter(into))]
pub queue: AQueue,
#[builder(default = 0, setter(into))]
pub number_of_restarts: u32,
}
impl<AQueue> Scheduler<AQueue>
where
AQueue: AsyncQueueable + Clone + Sync + 'static,
{
#[async_recursion(?Send)]
pub async fn start(&mut self) -> Result<(), Error> {
let join_handle: JoinHandle<Result<(), Error>> = self.schedule_loop().await;
match join_handle.await {
Err(err) => {
error!(
"Scheduler panicked, restarting {:?}. Number of restarts {}",
err, self.number_of_restarts
);
self.number_of_restarts += 1;
sleep(Duration::from_secs(1)).await;
self.start().await
}
Ok(task_res) => match task_res {
Err(err) => {
error!(
"Scheduler failed, restarting {:?}. Number of restarts {}",
err, self.number_of_restarts
);
self.number_of_restarts += 1;
self.start().await
}
Ok(_) => {
error!(
"Scheduler stopped. restarting. Number of restarts {}",
self.number_of_restarts
);
self.number_of_restarts += 1;
self.start().await
}
},
}
}
pub async fn schedule_loop(&mut self) -> JoinHandle<Result<(), Error>> {
let mut scheduler = self.clone();
tokio::spawn(async move {
let sleep_duration = scheduler.check_period;
loop {
scheduler.schedule().await?;
sleep(sleep_duration).await;
}
})
}
pub async fn schedule(&mut self) -> Result<(), Error> {
if let Some(tasks) = self.queue.fetch_periodic_tasks(self.error_margin).await? {
for task in tasks {
self.process_task(task).await?;
}
};
Ok(())
}
async fn process_task(&mut self, task: PeriodicTask) -> Result<(), Error> {
match task.scheduled_at {
None => {
self.queue.schedule_next_task(task).await?;
}
Some(_) => {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
self.queue.insert_task(&*actual_task).await?;
self.queue.schedule_next_task(task).await?;
}
}
Ok(())
}
}
#[cfg(test)]
#[derive(TypedBuilder)]
pub struct SchedulerTest<'a> {
#[builder(setter(into))]
pub check_period: Duration,
#[builder(setter(into))]
pub error_margin: Duration,
#[builder(setter(into))]
pub queue: &'a mut dyn AsyncQueueable,
#[builder(default = 0, setter(into))]
pub number_of_restarts: u32,
}
#[cfg(test)]
impl<'a> SchedulerTest<'a> {
async fn schedule_test(&mut self) -> Result<(), Error> {
let sleep_duration = self.check_period;
loop {
match self.queue.fetch_periodic_tasks(self.error_margin).await? {
Some(tasks) => {
for task in tasks {
self.process_task(task).await?;
}
return Ok(());
}
None => {
sleep(sleep_duration).await;
}
};
}
}
async fn process_task(&mut self, task: PeriodicTask) -> Result<(), Error> {
match task.scheduled_at {
None => {
self.queue.schedule_next_task(task).await?;
}
Some(_) => {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
self.queue.insert_task(&*actual_task).await?;
self.queue.schedule_next_task(task).await?;
}
}
Ok(())
}
}
#[cfg(test)]
mod async_scheduler_tests {
use super::SchedulerTest;
use crate::asynk::async_queue::AsyncQueueTest;
use crate::asynk::async_queue::AsyncQueueable;
use crate::asynk::async_queue::PeriodicTask;
use crate::asynk::AsyncError as Error;
use crate::asynk::AsyncRunnable;
use async_trait::async_trait;
use bb8_postgres::bb8::Pool;
use bb8_postgres::tokio_postgres::NoTls;
use bb8_postgres::PostgresConnectionManager;
use chrono::DateTime;
use chrono::Duration as OtherDuration;
use chrono::Utc;
use serde::{Deserialize, Serialize};
use std::time::Duration;
#[derive(Serialize, Deserialize)]
struct AsyncScheduledTask {
pub number: u16,
}
#[typetag::serde]
#[async_trait]
impl AsyncRunnable for AsyncScheduledTask {
async fn run(&self, _queueable: &mut dyn AsyncQueueable) -> Result<(), Error> {
Ok(())
}
fn task_type(&self) -> String {
"schedule".to_string()
}
}
#[tokio::test]
async fn schedules_tasks() {
let pool = pool().await;
let mut connection = pool.get().await.unwrap();
let transaction = connection.transaction().await.unwrap();
let mut test = AsyncQueueTest::builder().transaction(transaction).build();
let schedule_in_future = Utc::now() + OtherDuration::seconds(5);
let _periodic_task = insert_periodic_task(
&mut test,
&AsyncScheduledTask { number: 1 },
schedule_in_future,
10000,
)
.await;
let check_period: u64 = 1;
let error_margin_seconds: u64 = 2;
let mut scheduler = SchedulerTest::builder()
.check_period(Duration::from_secs(check_period))
.error_margin(Duration::from_secs(error_margin_seconds))
.queue(&mut test as &mut dyn AsyncQueueable)
.build();
// Scheduler start tricky not loop :)
scheduler.schedule_test().await.unwrap();
let task = scheduler
.queue
.fetch_and_touch_task(Some("schedule".to_string()))
.await
.unwrap()
.unwrap();
let metadata = task.metadata.as_object().unwrap();
let number = metadata["number"].as_u64();
let type_task = metadata["type"].as_str();
let runnable_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
assert_eq!("schedule", runnable_task.task_type());
assert_eq!(Some("AsyncScheduledTask"), type_task);
assert_eq!(Some(1), number);
}
async fn insert_periodic_task(
test: &mut AsyncQueueTest<'_>,
task: &dyn AsyncRunnable,
timestamp: DateTime<Utc>,
period_in_millis: i64,
) -> PeriodicTask {
test.insert_periodic_task(task, timestamp, period_in_millis)
.await
.unwrap()
}
async fn pool() -> Pool<PostgresConnectionManager<NoTls>> {
let pg_mgr = PostgresConnectionManager::new_from_stringlike(
"postgres://postgres:postgres@localhost/fang",
NoTls,
)
.unwrap();
Pool::builder().build(pg_mgr).await.unwrap()
}
}

View file

@ -1,3 +1,4 @@
use crate::async_runnable::Scheduled::*;
use crate::asynk::async_queue::AsyncQueueable;
use crate::asynk::async_queue::FangTaskState;
use crate::asynk::async_queue::Task;
@ -27,15 +28,20 @@ impl<AQueue> AsyncWorker<AQueue>
where
AQueue: AsyncQueueable + Clone + Sync + 'static,
{
pub async fn run(&mut self, task: Task) -> Result<(), Error> {
let result = self.execute_task(task).await;
pub async fn run(
&mut self,
task: Task,
actual_task: Box<dyn AsyncRunnable>,
) -> Result<(), Error> {
let result = self.execute_task(task, actual_task).await;
self.finalize_task(result).await
}
async fn execute_task(&mut self, task: Task) -> Result<Task, (Task, String)> {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
async fn execute_task(
&mut self,
task: Task,
actual_task: Box<dyn AsyncRunnable>,
) -> Result<Task, (Task, String)> {
let task_result = actual_task.run(&mut self.queue).await;
match task_result {
Ok(()) => Ok(task),
@ -88,14 +94,24 @@ where
pub async fn run_tasks(&mut self) -> Result<(), Error> {
loop {
//fetch task
match self
.queue
.fetch_and_touch_task(Some(self.task_type.clone()))
.await
{
Ok(Some(task)) => {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
// check if task is scheduled or not
if let Some(CronPattern(_)) = actual_task.cron() {
// program task
self.queue.schedule_task(&*actual_task).await?;
}
self.sleep_params.maybe_reset_sleep_period();
self.run(task).await?
// run scheduled task
self.run(task, actual_task).await?;
}
Ok(None) => {
self.sleep().await;
@ -126,15 +142,20 @@ pub struct AsyncWorkerTest<'a> {
#[cfg(test)]
impl<'a> AsyncWorkerTest<'a> {
pub async fn run(&mut self, task: Task) -> Result<(), Error> {
let result = self.execute_task(task).await;
pub async fn run(
&mut self,
task: Task,
actual_task: Box<dyn AsyncRunnable>,
) -> Result<(), Error> {
let result = self.execute_task(task, actual_task).await;
self.finalize_task(result).await
}
async fn execute_task(&mut self, task: Task) -> Result<Task, (Task, String)> {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
async fn execute_task(
&mut self,
task: Task,
actual_task: Box<dyn AsyncRunnable>,
) -> Result<Task, (Task, String)> {
let task_result = actual_task.run(self.queue).await;
match task_result {
Ok(()) => Ok(task),
@ -193,8 +214,17 @@ impl<'a> AsyncWorkerTest<'a> {
.await
{
Ok(Some(task)) => {
let actual_task: Box<dyn AsyncRunnable> =
serde_json::from_value(task.metadata.clone()).unwrap();
// check if task is scheduled or not
if let Some(CronPattern(_)) = actual_task.cron() {
// program task
self.queue.schedule_task(&*actual_task).await?;
}
self.sleep_params.maybe_reset_sleep_period();
self.run(task).await?
// run scheduled task
self.run(task, actual_task).await?;
}
Ok(None) => {
return Ok(());
@ -212,6 +242,7 @@ impl<'a> AsyncWorkerTest<'a> {
#[cfg(test)]
mod async_worker_tests {
use super::AsyncWorkerTest;
use crate::async_runnable::Scheduled;
use crate::asynk::async_queue::AsyncQueueTest;
use crate::asynk::async_queue::AsyncQueueable;
use crate::asynk::async_queue::FangTaskState;
@ -223,6 +254,8 @@ mod async_worker_tests {
use bb8_postgres::bb8::Pool;
use bb8_postgres::tokio_postgres::NoTls;
use bb8_postgres::PostgresConnectionManager;
use chrono::Duration;
use chrono::Utc;
use serde::{Deserialize, Serialize};
#[derive(Serialize, Deserialize)]
@ -237,6 +270,23 @@ mod async_worker_tests {
Ok(())
}
}
#[derive(Serialize, Deserialize)]
struct WorkerAsyncTaskSchedule {
pub number: u16,
}
#[typetag::serde]
#[async_trait]
impl AsyncRunnable for WorkerAsyncTaskSchedule {
async fn run(&self, _queueable: &mut dyn AsyncQueueable) -> Result<(), Error> {
Ok(())
}
fn cron(&self) -> Option<Scheduled> {
Some(Scheduled::ScheduleOnce(Utc::now() + Duration::seconds(7)))
}
}
#[derive(Serialize, Deserialize)]
struct AsyncFailedTask {
pub number: u16,
@ -290,8 +340,9 @@ mod async_worker_tests {
let transaction = connection.transaction().await.unwrap();
let mut test = AsyncQueueTest::builder().transaction(transaction).build();
let actual_task = WorkerAsyncTask { number: 1 };
let task = insert_task(&mut test, &WorkerAsyncTask { number: 1 }).await;
let task = insert_task(&mut test, &actual_task).await;
let id = task.id;
let mut worker = AsyncWorkerTest::builder()
@ -299,12 +350,48 @@ mod async_worker_tests {
.retention_mode(RetentionMode::KeepAll)
.build();
worker.run(task).await.unwrap();
worker.run(task, Box::new(actual_task)).await.unwrap();
let task_finished = test.find_task_by_id(id).await.unwrap();
assert_eq!(id, task_finished.id);
assert_eq!(FangTaskState::Finished, task_finished.state);
test.transaction.rollback().await.unwrap();
}
#[tokio::test]
async fn schedule_task_test() {
let pool = pool().await;
let mut connection = pool.get().await.unwrap();
let transaction = connection.transaction().await.unwrap();
let mut test = AsyncQueueTest::builder().transaction(transaction).build();
let actual_task = WorkerAsyncTaskSchedule { number: 1 };
let task = test.schedule_task(&actual_task).await.unwrap();
let id = task.id;
let mut worker = AsyncWorkerTest::builder()
.queue(&mut test as &mut dyn AsyncQueueable)
.retention_mode(RetentionMode::KeepAll)
.build();
worker.run_tasks_until_none().await.unwrap();
let task = worker.queue.find_task_by_id(id).await.unwrap();
assert_eq!(id, task.id);
assert_eq!(FangTaskState::New, task.state);
tokio::time::sleep(core::time::Duration::from_secs(10)).await;
worker.run_tasks_until_none().await.unwrap();
let task = test.find_task_by_id(id).await.unwrap();
assert_eq!(id, task.id);
assert_eq!(FangTaskState::Finished, task.state);
}
#[tokio::test]
async fn saves_error_for_failed_task() {
let pool = pool().await;
@ -312,8 +399,9 @@ mod async_worker_tests {
let transaction = connection.transaction().await.unwrap();
let mut test = AsyncQueueTest::builder().transaction(transaction).build();
let failed_task = AsyncFailedTask { number: 1 };
let task = insert_task(&mut test, &AsyncFailedTask { number: 1 }).await;
let task = insert_task(&mut test, &failed_task).await;
let id = task.id;
let mut worker = AsyncWorkerTest::builder()
@ -321,7 +409,7 @@ mod async_worker_tests {
.retention_mode(RetentionMode::KeepAll)
.build();
worker.run(task).await.unwrap();
worker.run(task, Box::new(failed_task)).await.unwrap();
let task_finished = test.find_task_by_id(id).await.unwrap();
assert_eq!(id, task_finished.id);
@ -367,6 +455,7 @@ mod async_worker_tests {
assert_eq!(FangTaskState::New, task2.state);
test.transaction.rollback().await.unwrap();
}
#[tokio::test]
async fn remove_when_finished() {
let pool = pool().await;

View file

@ -1,6 +1,5 @@
pub mod async_queue;
pub mod async_runnable;
pub mod async_scheduler;
pub mod async_worker;
pub mod async_worker_pool;

View file

@ -1 +1 @@
UPDATE "fang_tasks" SET "state" = $1 , "error_message" = $2 , "updated_at" = $3 WHERE id = $4 RETURNING id , state , metadata , error_message , task_type , created_at , updated_at
UPDATE "fang_tasks" SET "state" = $1 , "error_message" = $2 , "updated_at" = $3 WHERE id = $4 RETURNING *

View file

@ -1 +0,0 @@
SELECT * FROM fang_periodic_tasks WHERE scheduled_at BETWEEN $1 AND $2 OR scheduled_at IS NULL

View file

@ -1 +1 @@
SELECT * FROM fang_tasks WHERE state = 'new' AND task_type = $1 ORDER BY created_at ASC LIMIT 1 FOR UPDATE SKIP LOCKED
SELECT * FROM fang_tasks WHERE task_type = $1 AND state = 'new' AND $2 >= scheduled_at ORDER BY created_at ASC, scheduled_at ASC LIMIT 1 FOR UPDATE SKIP LOCKED

View file

@ -1 +0,0 @@
SELECT * FROM fang_periodic_tasks WHERE id = $1

View file

@ -1 +0,0 @@
SELECT * FROM fang_tasks WHERE metadata = $1 LIMIT 1

View file

@ -0,0 +1 @@
SELECT * FROM fang_tasks WHERE uniq_hash = $1 AND state = 'new' LIMIT 1

View file

@ -1 +0,0 @@
INSERT INTO "fang_periodic_tasks" ("metadata", "scheduled_at", "period_in_millis") VALUES ($1, $2, $3) RETURNING id , metadata , period_in_millis , scheduled_at , created_at , updated_at

View file

@ -1 +1 @@
INSERT INTO "fang_tasks" ("metadata", "task_type") VALUES ($1, $2) RETURNING id , state , metadata , error_message , task_type , created_at , updated_at
INSERT INTO "fang_tasks" ("metadata", "task_type", "scheduled_at") VALUES ($1, $2, $3) RETURNING *

View file

@ -0,0 +1 @@
INSERT INTO "fang_tasks" ("metadata", "task_type" , "uniq_hash", "scheduled_at") VALUES ($1, $2 , $3, $4) RETURNING *

View file

@ -1 +0,0 @@
DELETE FROM "fang_periodic_tasks"

View file

@ -1 +0,0 @@
UPDATE "fang_periodic_tasks" SET "scheduled_at" = $1 , "updated_at" = $2 RETURNING id , metadata , period_in_millis , scheduled_at , created_at , updated_at

View file

@ -1 +1 @@
UPDATE "fang_tasks" SET "state" = $1 , "updated_at" = $2 WHERE id = $3 RETURNING id , state , metadata , error_message , task_type , created_at , updated_at
UPDATE "fang_tasks" SET "state" = $1 , "updated_at" = $2 WHERE id = $3 RETURNING *

View file

@ -60,9 +60,16 @@ pub use typetag;
#[doc(hidden)]
pub extern crate serde;
#[doc(hidden)]
pub extern crate chrono;
#[doc(hidden)]
pub use serde_derive::{Deserialize, Serialize};
pub use chrono::DateTime;
pub use chrono::Utc;
pub use cron::Schedule;
#[cfg(feature = "blocking")]
pub mod blocking;
#[cfg(feature = "blocking")]