MQTT的学习研究（七）基于HTTP POST MQTT 发布消息服务端使用

参阅官方文档

http://publib.boulder.ibm.com/infocenter/wmqv7/v7r0/topic/com.ibm.mq.csqzau.doc/ts21220_.htm

HTTP POST puts a message to a queue, or a publication to a topic. The HTTPPOST Java sample is an example an HTTP POST request of a message to a queue. Instead of using Java, you could create an HTTPPOST request using a browser form, or an AJAX toolkit instead.

Figure 1 shows an HTTP request to put a message on a queue called myQueue. This request contains the HTTP header x-msg-correlId to set the correlation ID of the WebSphere MQ message.

Figure 1. Example of an HTTP POST request to a queue

POST /msg/queue/myQueue/ HTTP/1.1
Host: www.example.org
Content-Type: text/plain
x-msg-correlID: 1234567890
Content-Length: 50

Here's my message body that will appear on the queue.

Figure 2 shows the response sent back to the client. There is no response content.

Figure 2. Example of an HTTP POST response

HTTP/1.1 200 OK
Date: Wed, 2 Jan 2007 22:38:34 GMT
Server: Apache-Coyote/1.1 WMQ-HTTP/1.1 JEE-Bridge/1.1
Content-Length: 0

请求的协议格式和请求的响应格式

The HTTP POST operation puts a message on a WebSphere® MQ queue, or publishes a message to a topic.

Syntax

Request

>>-POST-- --| Path |-- --HTTP version--CRLF--------------------->

   .-CRLF---------------.  .-CRLF---------------.   
   V                    |  V                    |   
>----+----------------+-+----+----------------+-+--------------->
     '-general-header-'      '-request-header-'     

   .-CRLF----------------------------.        .-CRLF----.   
   V                                 |        V         |   
>----+-----------------------------+-+--CRLF----Message-+------><
     '-| entity header (Request) |-'                        

Path

|--/--contextRoot--/-------------------------------------------->

>--msg/--+-queue/--queueName--+-------------+-+--/--------------|
         |                    '-@--qMgrName-' |      
         '-topic/--topicName------------------'      

entity-header (Request)

|--+----------------------------------------------+-------------|
   +-standard entity-header-- --entity-value------+   
   +-x-msg-class-- --message type-----------------+   
   +-x-msg-correlId-- --correlation ID------------+   
   +-x-msg-encoding-- --encoding type-------------+   
   +-x-msg-expiry-- --duration--------------------+   
   +-x-msg-format-- --message format--------------+   
   +-x-msg-msgId-- --message ID-------------------+   
   +-x-msg-persistence-- --persistence------------+   
   +-x-msg-priority-- --priority class------------+   
   +-x-msg-replyTo-- --reply-to queue-------------+   
   +-x-msg-require-headers-- --entity header name-+   
   '-x-msg-usr-- --user properties----------------'   

Note:

1. If a question mark (?) is used it must be substituted with %3f. For example, orange?topic should be specified as orange%3ftopic.
2. @qMgrName is only valid on an HTTP POST

Response

>>-HTTP version-- --HTTP Status-Code-- --HTTP Reason-Phrase--CRLF-->

   .-CRLF---------------.  .-CRLF----------------.   
   V                    |  V                     |   
>----+----------------+-+----+-----------------+-+-------------->
     '-general-header-'      '-response-header-'     

   .-CRLF-----------------------------.   
   V                                  |   
>----+------------------------------+-+------------------------><
     '-| entity-header (Response) |-'     

entity-header (Response)

|--+-----------------------------------------+------------------|
   +-standard entity-header-- --entity-value-+   
   +-x-msg-class-- --message type------------+   
   +-x-msg-correlId-- --correlation ID-------+   
   +-x-msg-encoding-- --encoding type--------+   
   +-x-msg-expiry-- --duration---------------+   
   +-x-msg-format-- --message format---------+   
   +-x-msg-msgId-- --message ID--------------+   
   +-x-msg-persistence-- --persistence-------+   
   +-x-msg-priority-- --priority class-------+   
   +-x-msg-replyTo-- --reply-to queue--------+   
   +-x-msg-timestamp-- --HTTP-date-----------+   
   '-x-msg-usr-- --user properties-----------'   

HTTP POST方式实现如下：

1. package com.etrip.mqttv3.http;
2. /**
3. * This sample shows how to post a message. It has the same behaviour as the
4. * amqsput command in that it will read in lines from the command line and put
5. * them to the queue. It will put non-persistent String messages on to the queue
6. * with UNLIMITED expiry and LOW (0) priority. The program is terminated by
7. * either EOF being put into the entry line (^Z on windows) or a blank line.
8. * usage: java HTTPPOST <Queue (default=SYSTEM.DEFAULT.LOCAL.QUEUE)> <host:port
9. * (default localhost:8080> <context-root (the MQ Bridge for HTTP's
10. * context-root)>
11. */
12. import java.io.BufferedReader;
13. import java.io.BufferedWriter;
14. import java.io.IOException;
15. import java.io.InputStreamReader;
16. import java.io.OutputStream;
17. import java.io.OutputStreamWriter;
18. import java.net.HttpURLConnection;
19. import java.net.MalformedURLException;
20. import java.net.URL;
21. /**
22. *
23. * 采用HTTP POST发布相关的消息
24. *     The HTTP POST operation puts a message on a WebSphere® MQ queue, or publishes
25. *  a message to a topic.
26. *
27. *  发布消息到主题或者队列的路径：
28. *
29. *
30. *
31. *
32. *
33. * @author longgangbai
34. */
35. public class HTTPPOST
36. {
37. private static final String DEFAULT_HOST = "localhost";
38. private static final String DEFAULT_PORT = "8080";
39. private static final String DEFAULT_QUEUE = "SYSTEM.DEFAULT.LOCAL.QUEUE";
40. private static final String DEFAULT_CONTEXT_ROOT = "mq";
41. private static final String CRLF = "\r\n";
42. public static int MALFORMED_URL_EXCEPTION_RC = -1;
43. public static int END_IOEXCEPTION_RC = -2;
44. /**
45. * 构建发布主题队列路径
46. *
47. * @param host
48. * @param port
49. * @param context
50. * @param queueName
51. */
52. private static String getPublishQueueURL(String host, String port,
53. String context, String queueName) {
54. StringBuffer urlString =new StringBuffer("http://");
55. if(StringUtils.isEmtry(host)){
56. host=DEFAULT_HOST;
57. }
58. if(StringUtils.isEmtry(port)){
59. port=DEFAULT_PORT;
60. }
61. urlString.append(host).append(":").append(port);
62. if(StringUtils.isEmtry(context)){
63. context=DEFAULT_CONTEXT_ROOT;
64. }
65. urlString.append("/");
66. urlString.append(context);
67. urlString.append("/msg/queue/");
68. if(StringUtils.isEmtry(queueName)){
69. }
70. queueName=DEFAULT_QUEUE;
71. urlString.append(queueName);
72. System.out.println("urlString="+urlString);
73. return urlString.toString();
74. }
75. /**
76. *
77. * @param host
78. * @param port
79. * @param context
80. * @param queueName
81. * @param message
82. * @return
83. * @throws MalformedURLException
84. */
85. public static boolean publishTopic(String host,String port,String context,String queueName,String message ){
86. boolean response = true;
87. HttpURLConnection connection=null;
88. try {
89. String publishURL=getPublishQueueURL(host, port, context, queueName);
90. URL url=new URL(publishURL);
91. connection = (HttpURLConnection) url.openConnection();
92. /* Build the headers */
93. // the verb first
94. connection.setRequestMethod("POST");
95. // Content type is a string message
96. connection.setRequestProperty("content-type", "text/plain");
97. // set the message priority to low
98. connection.setRequestProperty("x-msg-priority", "LOW");
99. // Ensure we can get the output stream from the connection
100. connection.setDoOutput(true);
101. OutputStream outputStream = connection.getOutputStream();
102. // wrapper the outputstream in a writer
103. BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
104. outputStream));
105. // Now write the actual content.
106. // Make sure the CRLF is there in case some HTTP servers don't understand
107. // that it's the end of the message
108. writer.write(message + CRLF + CRLF);
109. writer.flush();
110. // now actually send the message
111. connection.connect();
112. // check the response for errors
113. int responseCode = connection.getResponseCode();
114. if (responseCode != 200)
115. {
116. String responseMessage =connection.getResponseMessage();
117. System.out.println("responsere sponseCode "+responseCode+" response request ="+responseMessage);
118. System.out.println("responsere context ");
119. BufferedReader reader = new BufferedReader(new InputStreamReader(
120. connection.getErrorStream()));
121. String line = null;
122. while ((line = reader.readLine()) != null)
123. {
124. System.out.println(line);
125. }
126. connection.disconnect();
127. response = false;
128. }else{
129. //获取相应的消息头信息
130. String responseQueueName=connection.getHeaderField("x-msg-replyTo");
131. System.out.println("responseQueueName="+responseQueueName);
132. System.out.println("response successful context :"+connection.getResponseMessage());
133. }
134. } catch (MalformedURLException e) {
135. response = false;
136. e.printStackTrace();
137. // TODO: handle exception
138. } catch (IOException e) {
139. response = false;
140. // TODO Auto-generated catch block
141. e.printStackTrace();
142. }finally{
143. connection.disconnect();
144. }
145. return response;
146. }
147. public static void main(String[] args) {
148. HTTPPOST.publishTopic("192.168.208.46", "8080", "mq", "java_lover", "this is a message ");
149. }
150. }

HTTP POST 发布主题请求协议和响应协议
http://publib.boulder.ibm.com/infocenter/wmqv7/v7r0/topic/com.ibm.mq.csqzau.doc/ts21220_.htm

请求响应头各个字段的含义的讲解
http://publib.boulder.ibm.com/infocenter/wmqv7/v7r0/topic/com.ibm.mq.csqzau.doc/ts21250_.htm

响应错误处理
http://publib.boulder.ibm.com/infocenter/wmqv7/v7r0/topic/com.ibm.mq.csqzau.doc/ts21340_.htm