Task (Elixir)

Task (Elixir)

Task in Elixir is a module that allows developers to work with concurrent programming and asynchronous execution. It provides a high-level interface for managing concurrent computations and enables efficient utilization of system resources.

Creating a Task

In order to create a task, the `Task.async/1` function is used. It takes a single argument, a function or a module and function tuple, that represents the task to be executed.

 task = Task.async(fn -> some_function() end)
 

The `Task.async/1` function returns a struct representing the task, which can be used later for tracking or interacting with the task.

Starting a Task

To start a task and execute it concurrently, the `Task.start/1` or `Task.await/1` function can be used. The `Task.start/1` function takes a task struct and starts its execution in a separate process.

 task_pid = Task.start(task)
 

The `task_pid` is the process identifier (PID) of the newly created process that executes the task.

The `Task.await/1` function can be used to wait for and get the result of a task's execution.

 task_result = Task.await(task)
 

Task Cancellation

Tasks can be cancelled using the `Task.cancel/1` or `Task.shutdown/1` function.

 Task.cancel(task)
 
 Task.shutdown(task)
 

The `Task.cancel/1` function cancels a task by sending a cancellation signal to the executing process. The `Task.shutdown/1` function, on the other hand, cancels a task and waits for its termination.

Task Supervision

Tasks can be supervised using the `Task.Supervisor` module. It provides functionality for creating and managing supervised tasks. Supervised tasks are automatically restarted in case of failure, ensuring fault-tolerance.

 supervisor = Task.Supervisor.start_link()
 task_spec = {Task, :async, [fn -> some_function() end]}
 task_ref = Task.Supervisor.async_nolink(supervisor, task_spec)
 

The `Task.Supervisor.async_nolink/2` function is used to create and start a supervised task without linking it to the supervisor process.

Task Monitoring

Tasks can be monitored using the `Task.monitor/1` function. It allows developers to receive notifications about task termination or abnormal termination.

 task_ref = Task.monitor(task)
 

The `Task.monitor/1` function returns a reference to the monitoring process, which can be used to receive notifications.

Summary

Task module in Elixir enables concurrent programming and asynchronous execution. Developers can create, start, monitor, and cancel tasks for efficient utilization of system resources. By leveraging task supervision, fault-tolerant systems can be built.

For more details on Task module, check the official Elixir documentation [1].