Struct PullMessageService 

pub struct PullMessageService { /* private fields */ }

RocketMQ Consumer Pull Message Service

Responsibilities

• Asynchronously schedules Pull/Pop message requests
• Supports both delayed and immediate scheduling
• Manages lifecycle of background pull tasks

Thread Model

• Main loop: Single Tokio task
• Delayed tasks: Individual tokio::spawn tasks

Shutdown Semantics

• shutdown() sends stop signal and waits for graceful termination
• Main loop processes current request before exiting
• Delayed tasks check is_stopped() before execution

Implementations

impl PullMessageService

pub fn new() -> Self

Creates a new PullMessageService instance

pub fn with_capacity(queue_capacity: usize) -> Self

Creates a new PullMessageService instance with custom queue capacity

pub fn is_stopped(&self) -> bool

Checks if the service is stopped

pub fn get_service_name(&self) -> &'static str

Gets service name

pub async fn start( &mut self, instance: ArcMut<MQClientInstance>, ) -> Result<(), RocketMQError>

Starts the pull message service

Arguments

• instance - MQClientInstance for message processing

Errors

Returns error if service is already started

pub fn execute_pull_request_later( &self, pull_request: PullRequest, time_delay: u64, )

Executes pull request with delay

Arguments

• pull_request - The pull request to execute
• time_delay - Delay in milliseconds before execution

Behavior

• Returns immediately if service is stopped
• Spawns a tokio task that sleeps then sends the request

pub async fn execute_pull_request_immediately(&self, pull_request: PullRequest)

Executes pull request immediately

Arguments

• pull_request - The pull request to execute

Behavior

Logs error but does not return error (aligned with Java implementation)

pub fn execute_pop_pull_request_later( &self, pop_request: PopRequest, time_delay: u64, )

Executes pop request with delay

pub async fn execute_pop_pull_request_immediately( &self, pop_request: PopRequest, )

Executes pop request immediately

pub fn execute_task_later<F>(&self, task: F, time_delay: u64)

where F: FnOnce() + Send + 'static,

Executes a generic task with delay (equivalent to Java’s executeTaskLater)

Arguments

• task - Task function to execute
• time_delay - Delay in milliseconds before execution

pub fn execute_task<F>(&self, task: F)

where F: FnOnce() + Send + 'static,

Executes a generic task immediately (equivalent to Java’s executeTask)

pub async fn shutdown(&self, timeout_ms: u64) -> Result<(), RocketMQError>

Gracefully shuts down the service

Arguments

• timeout_ms - Maximum time to wait for shutdown (milliseconds)

Behavior

• Sets stopped flag
• Sends shutdown signal to main loop
• Cancels all scheduled tasks
• Waits for main loop to finish (with timeout)

pub async fn shutdown_default(&self) -> Result<(), RocketMQError>

Shuts down with default timeout

Trait Implementations

impl Clone for PullMessageService

fn clone(&self) -> PullMessageService

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for PullMessageService

fn default() -> Self

Returns the “default value” for a type.