1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
#ifndef _QmfEngineResilientConnection_
#define _QmfEngineResilientConnection_
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
#include <qmf/engine/Message.h>
#include <qmf/engine/ConnectionSettings.h>
#include <string>
namespace qmf {
namespace engine {
class ResilientConnectionImpl;
/**
* Represents events that occur, unsolicited, from ResilientConnection.
*/
struct ResilientConnectionEvent {
enum EventKind {
CONNECTED = 1,
DISCONNECTED = 2,
SESSION_CLOSED = 3,
RECV = 4
};
EventKind kind;
void* sessionContext; // SESSION_CLOSED, RECV
char* errorText; // DISCONNECTED, SESSION_CLOSED
Message message; // RECV
};
class SessionHandle {
friend class ResilientConnectionImpl;
void* impl;
};
/**
* ResilientConnection represents a Qpid connection that is resilient.
*
* Upon creation, ResilientConnection attempts to establish a connection to the
* messaging broker. If it fails, it will continue to retry at an interval that
* increases over time (to a maximum interval). If an extablished connection is
* dropped, a reconnect will be attempted.
*/
class ResilientConnection {
public:
/**
* Create a new resilient connection.
*@param settings Settings that define how the connection is to be made.
*@param delayMin Minimum delay (in seconds) between retries.
*@param delayMax Maximum delay (in seconds) between retries.
*@param delayFactor Factor to multiply retry delay by after each failure.
*/
ResilientConnection(const ConnectionSettings& settings);
~ResilientConnection();
/**
* Get the connected status of the resilient connection.
*@return true iff the connection is established.
*/
bool isConnected() const;
/**
* Get the next event (if present) from the connection.
*@param event Returned event if one is available.
*@return true if event is valid, false if there are no more events to handle.
*/
bool getEvent(ResilientConnectionEvent& event);
/**
* Discard the event on the front of the queue. This should be invoked after processing
* the event from getEvent.
*/
void popEvent();
/**
* Create a new AMQP session.
*@param name Unique name for the session.
*@param sessionContext Optional user-context value that will be provided in events
* pertaining to this session.
*@param handle Output handle to be stored and used in subsequent calls pertaining to
* this session.
*@return true iff the session was successfully created.
*/
bool createSession(const char* name, void* sessionContext, SessionHandle& handle);
/**
* Destroy a created session.
*@param handle SessionHandle returned by createSession.
*/
void destroySession(SessionHandle handle);
/**
* Send a message into the AMQP broker via a session.
*@param handle The session handle of the session to transmit through.
*@param message The QMF message to transmit.
*/
void sendMessage(SessionHandle handle, Message& message);
/**
* Declare an exclusive, auto-delete queue for a session.
*@param handle The session handle for the owner of the queue.
*@param queue The name of the queue.
*/
void declareQueue(SessionHandle handle, char* queue);
/**
* Delete a queue.
*@param handle The session handle for the owner of the queue.
*@param queue The name of the queue.
*/
void deleteQueue(SessionHandle handle, char* queue);
/**
* Bind a queue to an exchange.
*@param handle The session handle of the session to use for binding.
*@param exchange The name of the exchange for binding.
*@param queue The name of the queue for binding.
*@param key The binding key.
*/
void bind(SessionHandle handle, char* exchange, char* queue, char* key);
/**
* Remove a binding.
*@param handle The session handle of the session to use for un-binding.
*@param exchange The name of the exchange.
*@param queue The name of the queue.
*@param key The binding key.
*/
void unbind(SessionHandle handle, char* exchange, char* queue, char* key);
/**
* Establish a file descriptor for event notification.
*@param fd A file descriptor into which the connection shall write a character each
* time an event is enqueued. This fd may be in a pair, the other fd of which
* is used in a select loop to control execution.
*/
void setNotifyFd(int fd);
/**
* Send a byte into the notify file descriptor.
*
* This can be used to wake up the event processing portion of the engine from either the
* wrapped implementation or the engine itself.
*/
void notify();
private:
ResilientConnectionImpl* impl;
};
}
}
#endif
|
