setter.h 文件参考

Write-side primitive of the VLink field communication model. 更多...

#include <memory>
#include <mutex>
#include <optional>
#include <string>
#include <type_traits>
#include "./impl/setter_impl.h"
#include "./node.h"
#include "./internal/setter-inl.h"

setter.h 的引用(Include)关系图:

此图展示该文件直接或间接的被哪些文件引用了:

浏览源代码.

类
class	vlink::Setter< ValueT, SecT >
	Type-safe latest-value writer for the VLink field communication model. 更多...
class	vlink::SecuritySetter< ValueT >
	Convenience alias of Setter with per-message encryption enabled. 更多...

命名空间
	vlink

详细描述

Write-side primitive of the VLink field communication model.

Setter<ValueT, SecT> publishes the latest value for a field topic. Every call to set() updates the locally cached value and emits the new serialised payload over the transport. When a late Getter joins after the setter has already written, an internally registered sync() callback resends the cached value so the late peer receives the current state immediately.

The class is a thin, header-only template wrapper around SetterImpl.

Field-model Data Flow

*   Setter<ValueT>             Transport Back-end             Getter<ValueT>
*   --------------             ------------------             ---------------
*      | set(v)                       |                              |
*      |  cache value                 |                              |
*      |  Serializer::serialize       |                              |
*      |----------------------------->|--- latest-value frame ------>|
*      |                              |  (overwrites any previous)   |
*      |                              |                              |--> callback(v)
*      |                              |                              |--> get() => v
*      | <-- late joiner sync ------- | <-- sync() fired by impl --- |
*      | re-emit cached value         |                              |
*      |----------------------------->|----------------------------->|
* 

Setter vs Publisher

Feature	Setter<T>	Publisher<T>
Transport role tag	kSetter	kPublisher
Latest-value retention	Re-sent to late-joining getters	No re-send to late subscribers
Sync-on-connect callback	Yes (registered inside init())	No
Cross-role bridge	mark_as_publisher()	mark_as_setter()

Durability and Persistence Modes

Setter inherits durability behaviour from the transport's effective Qos profile. Common configurations:

Durability mode	Behaviour
kVolatile	Cached in-process only; re-sent on local sync() hook.
kTransientLocal	Cached inside the transport writer for late subscribers.
kTransient	Persisted in an external durability service (DDS only).
kPersistent	Persisted to stable storage (DDS only).

Usage Example

vlink::Setter<MyStruct> setter("dds://vehicle/gear");
setter.set(MyStruct{3, "Drive"});
 
// A Getter that connects afterwards still receives the cached value:
vlink::Getter<MyStruct> getter("dds://vehicle/gear");
if (auto v = getter.get()) { use(*v); }

参见

getter.h, publisher.h, node.h, extension/qos.h