Struct TaskExecutor 

pub struct TaskExecutor { /* private fields */ }

Task executor for managing process lifecycle

TaskExecutor is the main entry point for executing system processes with real-time event monitoring, timeout management, and cross-platform process control. It coordinates process spawning, I/O handling, and termination through an event-driven architecture built on tokio.

Examples

Basic Process Execution

use tcrm_task::tasks::{config::TaskConfig, tokio::executor::TaskExecutor};
use tokio::sync::mpsc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    #[cfg(windows)]
    let config = TaskConfig::new("cmd").args(["/C", "echo", "Hello, World!"]);
    #[cfg(unix)]
    let config = TaskConfig::new("echo").args(["Hello, World!"]);
     
    config.validate()?;
     
    let (tx, mut rx) = mpsc::channel(100);
    let mut executor = TaskExecutor::new(config, tx);
     
    executor.coordinate_start().await?;
     
    while let Some(event) = rx.recv().await {
        match event {
            tcrm_task::tasks::event::TaskEvent::Output { line, .. } => {
                println!("Output: {}", line);
            }
            tcrm_task::tasks::event::TaskEvent::Stopped { .. } => break,
            _ => {}
        }
    }
     
    Ok(())
}

Process with Timeout and Termination

use tcrm_task::tasks::{
    config::TaskConfig,
    tokio::executor::TaskExecutor,
    control::TaskControl,
    event::TaskTerminateReason
};
use tokio::sync::mpsc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    #[cfg(windows)]
    let config = TaskConfig::new("cmd")
        .args(["/C", "timeout", "/t", "10"])
        .timeout_ms(5000);
    #[cfg(unix)]
    let config = TaskConfig::new("sleep")
        .args(["10"])
        .timeout_ms(5000);
     
    let (tx, mut rx) = mpsc::channel(100);
    let mut executor = TaskExecutor::new(config, tx);
     
    executor.coordinate_start().await?;
     
    // Terminate after 2 seconds
    tokio::spawn(async move {
        tokio::time::sleep(tokio::time::Duration::from_secs(2)).await;
        let _ = executor.terminate_task(TaskTerminateReason::UserRequested);
    });
     
    while let Some(event) = rx.recv().await {
        if matches!(event, tcrm_task::tasks::event::TaskEvent::Stopped { .. }) {
            break;
        }
    }
     
    Ok(())
}

Implementations

impl TaskExecutor

pub fn new(config: TaskConfig, event_tx: Sender<TaskEvent>) -> Self

Create a new task executor with the given configuration

Arguments

• config - Validated task configuration containing command, arguments, and options
• event_tx - Channel for sending task events

Examples

use tcrm_task::tasks::{config::TaskConfig, tokio::executor::TaskExecutor};
use tokio::sync::mpsc;

#[cfg(windows)]
let config = TaskConfig::new("cmd").args(["/C", "dir"]);
#[cfg(unix)]
let config = TaskConfig::new("ls").args(["-la"]);

let (tx, _rx) = mpsc::channel(100);
let executor = TaskExecutor::new(config, tx);

pub fn set_drop_event_tx_on_finished(&self, drop: bool)

Configures whether to drop (close) the event channel when the task finishes.

By default, the event channel (event_tx) is dropped when the task finishes, signaling to receivers that no more events will be sent. This method allows you to override that behavior, which is useful if you want to keep the event channel open for multiple tasks or for manual control.

Arguments

• drop - If true, the event channel will be dropped when the task finishes (default behavior). If false, the event channel will remain open after task completion.

Example

executor.set_drop_event_tx_on_finished(false); // Keep event channel open after task finishes

impl TaskExecutor

pub async fn send_stdin( &mut self, input: impl Into<String>, ) -> Result<(), TaskError>

Sends input to the process’s stdin.

Writes the provided input to the process’s stdin stream. The input will be automatically terminated with a newline if it doesn’t already end with one.

Arguments

• input - The input string to send to stdin

Returns

• Ok(()) - If the input was sent successfully
• Err(TaskError) - If sending fails or the task is not running

Errors

Returns TaskError::Control if the task is not in a running state, or TaskError::IO if writing to stdin fails

impl TaskExecutor

pub async fn coordinate_start(&mut self) -> Result<(), TaskError>

Start execution in a coordinated async event loop.

This is the main execution method that spawns the process, sets up event monitoring, and manages the complete process lifecycle. It handles stdout/stderr streaming, timeout management, termination signals, and process cleanup in a coordinated async event loop using `tokio::select!``.

Arguments

• event_tx - Channel sender for emitting [TaskEvent]s during process execution

Returns

• Ok(()) - Process coordination started successfully
• Err(TaskError) - Configuration validation or process spawning failed

Errors

Returns TaskError for:

• TaskError::InvalidConfiguration - Configuration validation failed
• TaskError::IO - Process spawning failed
• TaskError::Handle - Process handle or watcher setup failed

Events Emitted

During execution, the following events are sent via event_tx:

• [TaskEvent::Started] - Process spawned successfully
• [TaskEvent::Output] - Lines from stdout/stderr
• [TaskEvent::Ready] - Ready indicator detected (if configured)
• [TaskEvent::Stopped] - Process completed with exit code
• [TaskEvent::Error] - Errors during execution

Examples

Basic Usage

use tcrm_task::tasks::{config::TaskConfig, tokio::executor::TaskExecutor};
use tokio::sync::mpsc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    #[cfg(windows)]
    let config = TaskConfig::new("cmd").args(["/C", "echo", "test"]);
    #[cfg(unix)]
    let config = TaskConfig::new("echo").args(["test"]);
     
    config.validate()?;
     
    let (tx, mut rx) = mpsc::channel(100);
    let mut executor = TaskExecutor::new(config, tx);
     
    // Start coordination - returns immediately, process runs in background
    executor.coordinate_start().await?;
     
    // Process events until completion
    while let Some(event) = rx.recv().await {
        println!("Event: {:?}", event);
        if matches!(event, tcrm_task::tasks::event::TaskEvent::Stopped { .. }) {
            break;
        }
    }
     
    Ok(())
}

With Ready Indicator

use tcrm_task::tasks::{
    config::{TaskConfig, StreamSource},
    tokio::executor::TaskExecutor,
    event::TaskEvent
};
use tokio::sync::mpsc;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    #[cfg(windows)]
    let config = TaskConfig::new("cmd")
        .args(["/C", "echo", "Server ready"])
        .ready_indicator("Server ready")
        .ready_indicator_source(StreamSource::Stdout);
     
    #[cfg(unix)]
    let config = TaskConfig::new("echo")
        .args(["Server ready"])
        .ready_indicator("Server ready")
        .ready_indicator_source(StreamSource::Stdout);
     
    let (tx, mut rx) = mpsc::channel(100);
    let mut executor = TaskExecutor::new(config, tx);
     
    executor.coordinate_start().await?;
     
    while let Some(event) = rx.recv().await {
        match event {
            TaskEvent::Ready => {
                println!("Process is ready!");
                // Can now interact with the running process
            }
            TaskEvent::Stopped { .. } => break,
            _ => {}
        }
    }
     
    Ok(())
}

Trait Implementations

impl Debug for TaskExecutor

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl ProcessControl for TaskExecutor

async fn perform_process_action( &mut self, action: ProcessControlAction, ) -> Result<(), TaskError>

Performs a control action on the process or process group.

fn stop_process(&mut self) -> impl Future<Output = Result<(), TaskError>>

Requests the process to stop execution.

fn pause_process(&mut self) -> impl Future<Output = Result<(), TaskError>>

Requests the process to pause execution.

fn resume_process(&mut self) -> impl Future<Output = Result<(), TaskError>>

Requests the process to resume execution if it is paused.

impl TaskControl for TaskExecutor

fn terminate_task( &mut self, reason: TaskTerminateReason, ) -> Result<(), TaskError>

Terminates the task with the specified reason.

impl TaskStatusInfo for TaskExecutor

fn get_task_state(&self) -> TaskState

Gets the current state of the task.

fn get_process_state(&self) -> ProcessState

Gets the current state of the process.

fn get_process_id(&self) -> Option<u32>

Gets the process ID of the running task.

fn get_create_at(&self) -> SystemTime

Gets the creation timestamp of the task.

fn get_running_at(&self) -> Option<SystemTime>

Gets the timestamp when the task started running.

fn get_finished_at(&self) -> Option<SystemTime>

Gets the timestamp when the task finished.

fn get_exit_code(&self) -> Option<i32>

Gets the exit code of the finished task.

fn get_last_signal_code(&self) -> Option<Signal>

Gets the last received signal (if any) from the process.

fn get_information(&self) -> TaskInformation

Gets all information about the task.