database::async::async_result< T > Class Template Reference

Template class for asynchronous operation results. More...

#include <async_operations.h>

Collaboration diagram for database::async::async_result< T >:

Public Member Functions
	async_result (std::future< T > future)
T	get ()
T	get_for (std::chrono::milliseconds timeout)
bool	is_ready () const
std::future_status	wait_for (std::chrono::milliseconds timeout) const
template<concepts::VoidCallable< T > Callback>
void	then (Callback &&callback)
template<concepts::ErrorHandler Handler>
void	on_error (Handler &&error_handler)
void	then (std::function< void(T)> callback)
void	on_error (std::function< void(const std::exception &)> error_handler)

Private Attributes
std::future< T >	future_
std::mutex	callback_mutex_
std::function< void(T)>	success_callback_
std::function< void(const std::exception &)>	error_callback_

Detailed Description

template<typename T>
class database::async::async_result< T >

Template class for asynchronous operation results.

Thread-safety: Callback registration methods (then, on_error) are thread-safe. get() and get_for() should only be called once as they consume the future.

Definition at line 90 of file async_operations.h.

Constructor & Destructor Documentation

async_result()

template<typename T >

database::async::async_result< T >::async_result

(

std::future< T >

future

)

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 125 of file async_operations.h.

        : future_(std::move(future))
    {
    }

Member Function Documentation

get()

template<typename T >

T database::async::async_result< T >::get

(

)

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 131 of file async_operations.h.

    {
        std::function<void(T)> on_success;
        std::function<void(const std::exception&)> on_error_cb;
        {
            std::lock_guard<std::mutex> lock(callback_mutex_);
            on_success = success_callback_;
            on_error_cb = error_callback_;
        }
 
        try {
            T value = future_.get();
            if (on_success) {
                on_success(value);
            }
            return value;
        } catch (const std::exception& e) {
            if (on_error_cb) {
                on_error_cb(e);
            }
            throw;
        }
    }

Referenced by TEST_F(), and database::async::transaction_coordinator::two_phase_commit().

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get_for()

template<typename T >

T database::async::async_result< T >::get_for

(

std::chrono::milliseconds

timeout

)

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 156 of file async_operations.h.

    {
        auto status = future_.wait_for(timeout);
        if (status == std::future_status::timeout) {
            throw std::runtime_error("async_result::get_for timed out");
        }
        return get();
    }

References database::timeout.

Referenced by TEST_F().

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is_ready()

template<typename T >

bool database::async::async_result< T >::is_ready

(

)

const

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 166 of file async_operations.h.

    {
        return future_.wait_for(std::chrono::milliseconds(0)) == std::future_status::ready;
    }

Referenced by TEST_F(), and TEST_F().

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on_error() [1/2]

template<typename T >

template<concepts::ErrorHandler Handler>

void database::async::async_result< T >::on_error

(

Handler &&

error_handler

)

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 187 of file async_operations.h.

    {
        std::lock_guard<std::mutex> lock(callback_mutex_);
        error_callback_ = std::forward<Handler>(error_handler);
    }

on_error() [2/2]

template<typename T >

void database::async::async_result< T >::on_error

(

std::function< void(const std::exception &)>

error_handler

)

Definition at line 201 of file async_operations.h.

    {
        std::lock_guard<std::mutex> lock(callback_mutex_);
        error_callback_ = std::move(error_handler);
    }

then() [1/2]

template<typename T >

template<concepts::VoidCallable< T > Callback>

void database::async::async_result< T >::then

(

Callback &&

callback

)

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 179 of file async_operations.h.

    {
        std::lock_guard<std::mutex> lock(callback_mutex_);
        success_callback_ = std::forward<Callback>(callback);
    }

then() [2/2]

template<typename T >

void database::async::async_result< T >::then

(

std::function< void(T)>

callback

)

Definition at line 194 of file async_operations.h.

    {
        std::lock_guard<std::mutex> lock(callback_mutex_);
        success_callback_ = std::move(callback);
    }

wait_for()

template<typename T >

std::future_status database::async::async_result< T >::wait_for

(

std::chrono::milliseconds

timeout

)

const

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 172 of file async_operations.h.

    {
        return future_.wait_for(timeout);
    }

References database::timeout.

Referenced by TEST_F().

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Member Data Documentation

callback_mutex_

template<typename T >

std::mutex database::async::async_result< T >::callback_mutex_

mutableprivate

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 117 of file async_operations.h.

error_callback_

template<typename T >

std::function<void(const std::exception&)> database::async::async_result< T >::error_callback_

private

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 119 of file async_operations.h.

future_

template<typename T >

std::future<T> database::async::async_result< T >::future_

private

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 116 of file async_operations.h.

success_callback_

template<typename T >

std::function<void(T)> database::async::async_result< T >::success_callback_

private

Examples

/home/runner/work/database_system/database_system/database/async/async_operations.h.

Definition at line 118 of file async_operations.h.

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The documentation for this class was generated from the following file:

• database/async/async_operations.h