hmbdc
simplify-high-performance-messaging-programming
Sender.hpp
1 #include "hmbdc/Copyright.hpp"
2 #pragma once
3 #include "hmbdc/app/udpcast/SendTransportEngine.hpp"
4 
5 #include <type_traits>
6 #include <memory>
7 
8 namespace hmbdc { namespace app { namespace udpcast {
9 struct NetContext;
10 /**
11  * @brief fascade class for sending network messages
12  */
13 
14 struct Sender {
15  using ptr = std::shared_ptr<Sender>;
16 
17 private:
18  friend struct hmbdc::app::udpcast::NetContext;
19  Sender(SendTransport::ptr transport, Topic const& t)
20  : transport_(transport)
21  , topic_(t) {
22  }
23 
24 public:
25 
26  /**
27  * @brief send a message's first bytes
28  * @details the bytes length could be larger than Message, but needs to
29  * be able to fit in the tansport buffer the sender is associated
30  * with - exception thrown otherwise
31  *
32  * @param msg the message to send
33  * @tparam Message Type
34  * @param len just send the first len bytes of this message
35  * @tparam T integral type
36  */
37  template <typename Message, typename T
38  , typename = std::enable_if<std::is_integral<T>::value>>
39  void send(Message&& msg, T len) {
40  using raw = typename std::remove_reference<Message>::type;
41  static_assert(std::is_trivially_destructible<raw>::value, "cannot send message with dtor");
42  transport_->queueBytes(
43  topic_, raw::typeTag, &msg, static_cast<size_t>(len));
44  }
45 
46  /**
47  * @brief send a batch of message asynchronizely
48  * @details although batching could implicitly happen
49  * further performance gain could be achieved by sending more msg in
50  * a batch here
51  *
52  * @param m Message
53  * @tparam Message Type
54  */
55  template <typename... Messages>
56  void send(Messages&&... msgs) {
57  transport_->queue(topic_, std::forward<Messages>(msgs)...);
58  }
59 
60  /**
61  * @brief send a batch of message asynchronizely
62  * @details this call does not block and is transactional - all or none is queued
63  *
64  * @param m Message
65  * @tparam Message Type
66  *
67  * @return true if messages are queued successfully
68  */
69  template <typename... Messages>
70  bool trySend(Messages&&... msgs) {
71  return transport_->tryQueue(topic_, std::forward<Messages>(msgs)...);
72  }
73 
74  /**
75  * @brief send a message asynchronizely - avoiding Message copying
76  * by directly constructing the message in the buffer
77  *
78  * @param args Message's ctor args to construct the Message in the buffer
79  * @tparam Message Type
80  * @tparam typename ... Args args type
81  */
82  template <typename Message, typename ... Args>
83  void sendInPlace(Args&&... args) {
84  transport_->template queueInPlace<Message>(topic_, std::forward<Args>(args)...);
85  }
86 
87  /**
88  * @brief send a message asynchronizely by providing message
89  * in tag and bytes
90  * @details for runtime typed usage when the message type can only be decided
91  * at runtime
92  *
93  * @param tag message tag
94  * @param bytes message byte starting address
95  * @param len byte length of the above
96  */
97  void sendBytes(uint16_t tag, void const* bytes, size_t len) {
98  transport_->queueBytes(topic_, tag, bytes, len);
99  }
100 
101 private:
102  SendTransport::ptr transport_;
103  comm::Topic topic_;
104 };
105 }}}
a singleton that holding udpcast resources
Definition: NetContext.hpp:38
topic as in the publish / subscribe communication paradigm
Definition: Topic.hpp:14
void send(Messages &&... msgs)
send a batch of message asynchronizely
Definition: Sender.hpp:56
bool trySend(Messages &&... msgs)
send a batch of message asynchronizely
Definition: Sender.hpp:70
void send(Message &&msg, T len)
send a message&#39;s first bytes
Definition: Sender.hpp:39
void sendInPlace(Args &&... args)
send a message asynchronizely - avoiding Message copying by directly constructing the message in the ...
Definition: Sender.hpp:83
fascade class for sending network messages
Definition: Sender.hpp:14
void sendBytes(uint16_t tag, void const *bytes, size_t len)
send a message asynchronizely by providing message in tag and bytes
Definition: Sender.hpp:97
Definition: Base.hpp:12