Library provides periodic task executions on top of db-queue library.
Project uses Semantic Versioning.
Library is available on Maven Central.
implementation 'ru.yoomoney.tech:db-queue-scheduler-core:3.0.0',
'ru.yoomoney.tech:db-queue-scheduler-spring:3.0.0'
- Persisted periodic tasks;
- At most once task execution at the same time;
- Different schedule configuration: cron expressions, fixed rates, fixed delays, dynamic calculations;
- Tracing support;
- Task event listeners to build up monitoring;
- Many other features.
The library provides only (recurring tasks)/(periodic tasks)/(scheduled tasks) functionality - that allows executing tasks periodically. If you need one-time tasks - tasks that are executed once, please, look at db-queue library.
The project uses db-queue to work with a database.
The library requires a single database table where periodic tasks are stored.
CREATE TABLE scheduled_tasks (
id BIGSERIAL PRIMARY KEY,
queue_name TEXT NOT NULL,
payload TEXT,
created_at TIMESTAMP WITH TIME ZONE DEFAULT now(),
next_process_at TIMESTAMP WITH TIME ZONE DEFAULT now(),
attempt INTEGER DEFAULT 0,
reenqueue_attempt INTEGER DEFAULT 0,
total_attempt INTEGER DEFAULT 0
);
CREATE UNIQUE INDEX scheduled_tasks_uq ON scheduled_tasks (queue_name);CREATE TABLE scheduled_tasks (
id INT IDENTITY(1,1) NOT NULL,
queue_name VARCHAR(100) NOT NULL,
payload TEXT,
created_at DATETIMEOFFSET NOT NULL DEFAULT SYSDATETIMEOFFSET(),
next_process_at DATETIMEOFFSET NOT NULL DEFAULT SYSDATETIMEOFFSET(),
attempt INTEGER NOT NULL DEFAULT 0,
reenqueue_attempt INTEGER NOT NULL DEFAULT 0,
total_attempt INTEGER NOT NULL DEFAULT 0,
PRIMARY KEY (id)
);
CREATE UNIQUE INDEX scheduled_tasks_uq ON scheduled_tasks (queue_name);CREATE TABLE scheduled_tasks (
id NUMBER(38) NOT NULL PRIMARY KEY,
queue_name VARCHAR2(128) NOT NULL,
payload CLOB,
created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
next_process_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
attempt NUMBER(38) DEFAULT 0,
reenqueue_attempt NUMBER(38) DEFAULT 0,
total_attempt NUMBER(38) DEFAULT 0
);
CREATE UNIQUE INDEX scheduled_tasks_uq ON scheduled_tasks (queue_name);
-- Create sequence and specify its name through scheduler configurator.
CREATE SEQUENCE scheduled_tasks_seq;CREATE TABLE scheduled_tasks (
id BIGSERIAL PRIMARY KEY,
queue_name VARCHAR(100) NOT NULL,
payload VARCHAR(100),
created_at TIMESTAMP WITH TIME ZONE DEFAULT now(),
next_process_at TIMESTAMP WITH TIME ZONE DEFAULT now(),
attempt INTEGER DEFAULT 0,
reenqueue_attempt INTEGER DEFAULT 0,
total_attempt INTEGER DEFAULT 0
);
CREATE UNIQUE INDEX scheduled_tasks_uq ON scheduled_tasks (queue_name);Scheduler scheduler = new SpringSchedulerConfigurator()
.withDatabaseDialect(DatabaseDialect.POSTGRESQL)
.withTableName("scheduled_tasks")
.withJdbcOperations(jdbcTemplate)
.withTransactionOperations(transactionTemplate)
.configure();
ScheduledTask task = SimpleScheduledTask.create(
"scheduled-task-id",
context -> {
System.out.println("Hello World!");
return ScheduledTaskExecutionResult.success();
});
ScheduledTaskSettings settings = ScheduledTaskSettings.builder()
.withScheduleSettings(ScheduleSettings.fixedDelay(Duration.ofHours(1L)))
.withFailureSettings(FailureSettings.none())
.build()
scheduler.schedule(task, settings);
scheduler.start();See also our runnable example.
- When a new scheduled task
is registered, the library creates a new
db-queuequeue that linked exactly to the registeredscheduled task; - If the
db-queuequeue does not have a task, the library creates a new one and postpones it according to the linked schedule settings; - Each
db-queuequeue have a consumer that executes its linkedscheduled task; - When the consumer got a
db-queuetask it does the following steps:- Postponing the next execution time of the
db-queuetask according to the linked schedule settings and failure settings; - Starting HeartbeatAgent to prevent concurrent execution of the same task by different application nodes in case of a time-consuming execution;
- Executing the linked
scheduled task; - Postponing
db-queuetask according to the result of the last execution of the linkedscheduled task.
- Postponing the next execution time of the
The library lets configure ScheduleSettings
and FailureSettings.
FailureSettings is applied each time when an execution result is ERROR and the following conditions are true:
- The execution task attempts since the last successful one is less than
FailureSettings.maxAttempts; ScheduleSettings.CronSettingsis not configured, or the next execution time computed viaFailureSettingsis earlier than the one computed viaScheduleSettings.CronSettings.
Just fork the repo and send us a pull request.
Make sure your branch builds without any warnings/issues.
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent