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svn commit: r955411 [2/10] - in /qpid/site/docs/books:
0.5/AMQP-Messaging-Broker-CPP-Book/html/
0.5/Programming-In-Apache-Qpid/html/ 0.5/Programming-In-Apache-Qpid/pdf/
0.6/AMQP-Messaging-Broker-CPP-Book/html/
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Modified: qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02.html
URL: http://svn.apache.org/viewvc/qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02.html?rev=955411&r1=955410&r2=955411&view=diff
==============================================================================
--- qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02.html (original)
+++ qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02.html Wed Jun 16 22:01:44 2010
@@ -1,4 +1,4 @@
-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 2. Using the Qpid Messaging API</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="index.html" title="Programming in Apache Qpid"><link rel="prev" href="ch01.html" title="Chapter 1. Introduction"><link rel="next" href="ch02s02.html" title="2. A Simple Messaging Program in Python"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 2. Using the Qpid Messaging API</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch01.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ch02s02.html">Next</a></td></tr></table><hr></div><div class="chapter"
title="Chapter 2. Using the Qpid Messaging API"><div class="titlepage"><div><div><h2 class="title"><a name="id2604821"></a>Chapter 2. Using the Qpid Messaging API</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="ch02.html#id2588066">1. A Simple Messaging Program in C++</a></span></dt><dt><span class="section"><a href="ch02s02.html">2. A Simple Messaging Program in Python</a></span></dt><dt><span class="section"><a href="ch02s03.html">3. Addresses</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s03.html#id2598210">3.1. Address Strings</a></span></dt><dt><span class="section"><a href="ch02s03.html#id2607393">3.2. Subjects</a></span></dt><dt><span class="section"><a href="ch02s03.html#id2594787">3.3. Address String Options</a></span></dt><dt><span class="section"><a href="ch02s03.html#section-address-string-bnf">3.4. Address String Grammar</a></span></dt></dl></dd><dt><span class="section"><a href="ch
02s04.html">4. Logging</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s04.html#id2564826">4.1. Logging in C++</a></span></dt><dt><span class="section"><a href="ch02s04.html#id2564858">4.2. Logging in Python</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s05.html">5. Receiving Messages from Multiple Sources</a></span></dt><dt><span class="section"><a href="ch02s06.html">6. Request / Response</a></span></dt><dt><span class="section"><a href="ch02s07.html">7. Maps in Message Content</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s07.html#section-Python-Maps">7.1. Qpid Maps in Python</a></span></dt><dt><span class="section"><a href="ch02s07.html#section-cpp-Maps">7.2. Qpid Maps in C++</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s08.html">8. Performance</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s08.html#id2563236">8.1. Batching Acknowledgements</a></span></dt><dt><span class="section"><a href="
ch02s08.html#id2563245">8.2. Prefetch</a></span></dt><dt><span class="section"><a href="ch02s08.html#id2622677">8.3. Sizing the Replay Buffer</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s09.html">9. Reliability</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s09.html#id2622733">9.1. Reconnect</a></span></dt><dt><span class="section"><a href="ch02s09.html#id2622956">9.2. Guaranteed Delivery</a></span></dt><dt><span class="section"><a href="ch02s09.html#id2623004">9.3. Reliability Options in Senders and Receivers</a></span></dt><dt><span class="section"><a href="ch02s09.html#id2623104">9.4. Cluster Failover</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s10.html">10. Security</a></span></dt><dt><span class="section"><a href="ch02s11.html">11. Transactions</a></span></dt><dt><span class="section"><a href="ch02s12.html">12. The AMQP 0-10 mapping</a></span></dt></dl></div><p>The Qpid Messaging API is quite simple, consisting of o
nly a
+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 2. Using the Qpid Messaging API</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="index.html" title="Programming in Apache Qpid"><link rel="prev" href="ch01.html" title="Chapter 1. Introduction"><link rel="next" href="ch02s02.html" title="2. A Simple Messaging Program in Python"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 2. Using the Qpid Messaging API</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch01.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ch02s02.html">Next</a></td></tr></table><hr></div><div class="chapter"
title="Chapter 2. Using the Qpid Messaging API"><div class="titlepage"><div><div><h2 class="title"><a name="id2755578"></a>Chapter 2. Using the Qpid Messaging API</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="ch02.html#id2782717">1. A Simple Messaging Program in C++</a></span></dt><dt><span class="section"><a href="ch02s02.html">2. A Simple Messaging Program in Python</a></span></dt><dt><span class="section"><a href="ch02s03.html">3. A Simple Messaging Program in .NET C#</a></span></dt><dt><span class="section"><a href="ch02s04.html">4. Addresses</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s04.html#id2762724">4.1. Address Strings</a></span></dt><dt><span class="section"><a href="ch02s04.html#id2779643">4.2. Subjects</a></span></dt><dt><span class="section"><a href="ch02s04.html#id2758496">4.3. Address String Options</a></span></dt><dt><span class="section"><a href="ch02s04.html#section-addre
ss-string-bnf">4.4. Address String Grammar</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s05.html">5. Logging</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s05.html#id2743901">5.1. Logging in C++</a></span></dt><dt><span class="section"><a href="ch02s05.html#id2743934">5.2. Logging in Python</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s06.html">6. Receiving Messages from Multiple Sources</a></span></dt><dt><span class="section"><a href="ch02s07.html">7. Request / Response</a></span></dt><dt><span class="section"><a href="ch02s08.html">8. Maps in Message Content</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s08.html#section-Python-Maps">8.1. Qpid Maps in Python</a></span></dt><dt><span class="section"><a href="ch02s08.html#section-cpp-Maps">8.2. Qpid Maps in C++</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s09.html">9. Performance</a></span></dt><dd><dl><dt><span class="section"><a href="
ch02s09.html#id2727820">9.1. Batching Acknowledgements</a></span></dt><dt><span class="section"><a href="ch02s09.html#id2727840">9.2. Prefetch</a></span></dt><dt><span class="section"><a href="ch02s09.html#id2787527">9.3. Sizing the Replay Buffer</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s10.html">10. Reliability</a></span></dt><dd><dl><dt><span class="section"><a href="ch02s10.html#id2787575">10.1. Reconnect</a></span></dt><dt><span class="section"><a href="ch02s10.html#id2787798">10.2. Guaranteed Delivery</a></span></dt><dt><span class="section"><a href="ch02s10.html#id2787839">10.3. Reliability Options in Senders and Receivers</a></span></dt><dt><span class="section"><a href="ch02s10.html#id2787939">10.4. Cluster Failover</a></span></dt></dl></dd><dt><span class="section"><a href="ch02s11.html">11. Security</a></span></dt><dt><span class="section"><a href="ch02s12.html">12. Transactions</a></span></dt><dt><span class="section"><a href="ch02s13.html">
13. The AMQP 0-10 mapping</a></span></dt></dl></div><p>The Qpid Messaging API is quite simple, consisting of only a
handful of core classes.
</p><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"><p>
A <em class="firstterm">message</em> consists of a standard set
@@ -26,9 +26,9 @@
</p></li></ul></div><p>
The following sections show how to use these classes in a
simple messaging program.
- </p><div class="section" title="1. A Simple Messaging Program in C++"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2588066"></a>1. A Simple Messaging Program in C++</h2></div></div></div><p>The following C++ program shows how to create a connection,
+ </p><div class="section" title="1. A Simple Messaging Program in C++"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2782717"></a>1. A Simple Messaging Program in C++</h2></div></div></div><p>The following C++ program shows how to create a connection,
create a session, send messages using a sender, and receive
- messages using a receiver.</p><div class="example"><a name="id2618921"></a><p class="title"><b>Example 2.1. "Hello world!" in C++</b></p><div class="example-contents"><pre lang="c++" class="programlisting">
+ messages using a receiver.</p><div class="example"><a name="id2782038"></a><p class="title"><b>Example 2.1. "Hello world!" in C++</b></p><div class="example-contents"><pre lang="c++" class="programlisting">
#include <qpid/messaging/Connection.h>
#include <qpid/messaging/Message.h>
#include <qpid/messaging/Receiver.h>
@@ -44,23 +44,23 @@ int main(int argc, char** argv) {
std::string address = argc > 2 ? argv[2] : "amq.topic";
Connection connection(broker);
try {
- connection.open(); <a class="co" name="hello-cpp-open" href="ch02.html#callout-cpp-open"><img src="images/callouts/1.png" alt="1" border="0"></a>
- Session session = connection.createSession(); <a class="co" name="hello-cpp-session" href="ch02.html#callout-cpp-session"><img src="images/callouts/2.png" alt="2" border="0"></a>
+ connection.open(); <a class="co" name="hello-cpp-open" href="ch02.html#callout-cpp-open">(1)</a>
+ Session session = connection.createSession(); <a class="co" name="hello-cpp-session" href="ch02.html#callout-cpp-session">(2)</a>
- Receiver receiver = session.createReceiver(address); <a class="co" name="hello-cpp-receiver" href="ch02.html#callout-cpp-receiver"><img src="images/callouts/3.png" alt="3" border="0"></a>
- Sender sender = session.createSender(address); <a class="co" name="hello-cpp-sender" href="ch02.html#callout-cpp-sender"><img src="images/callouts/4.png" alt="4" border="0"></a>
+ Receiver receiver = session.createReceiver(address); <a class="co" name="hello-cpp-receiver" href="ch02.html#callout-cpp-receiver">(3)</a>
+ Sender sender = session.createSender(address); <a class="co" name="hello-cpp-sender" href="ch02.html#callout-cpp-sender">(4)</a>
sender.send(Message("Hello world!"));
- Message message = receiver.fetch(Duration::SECOND * 1); <a class="co" name="hello-cpp-fetch" href="ch02.html#callout-cpp-fetch"><img src="images/callouts/5.png" alt="5" border="0"></a>
+ Message message = receiver.fetch(Duration::SECOND * 1); <a class="co" name="hello-cpp-fetch" href="ch02.html#callout-cpp-fetch">(5)</a>
std::cout << message.getContent() << std::endl;
- session.acknowledge(); <a class="co" name="hello-cpp-acknowledge" href="ch02.html#callout-cpp-acknowledge"><img src="images/callouts/6.png" alt="6" border="0"></a>
+ session.acknowledge(); <a class="co" name="hello-cpp-acknowledge" href="ch02.html#callout-cpp-acknowledge">(6)</a>
- connection.close(); <a class="co" name="hello-cpp-close" href="ch02.html#callout-cpp-close"><img src="images/callouts/7.png" alt="7" border="0"></a>
+ connection.close(); <a class="co" name="hello-cpp-close" href="ch02.html#callout-cpp-close">(7)</a>
return 0;
} catch(const std::exception& error) {
std::cerr << error.what() << std::endl;
connection.close();
return 1;
}
-}</pre><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-open"></a><a href="#hello-cpp-open"><img src="images/callouts/1.png" alt="1" border="0"></a> </p></td><td valign="top" align="left"><p>Establishes the connection with the messaging broker.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-session"></a><a href="#hello-cpp-session"><img src="images/callouts/2.png" alt="2" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a session object, which maintains the state of all interactions with the messaging broker, and manages senders and receivers.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-receiver"></a><a href="#hello-cpp-receiver"><img src="images/callouts/3.png" alt="3" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a receiver that reads from the given address.</p></td></tr><tr><td w
idth="5%" valign="top" align="left"><p><a name="callout-cpp-sender"></a><a href="#hello-cpp-sender"><img src="images/callouts/4.png" alt="4" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a sender that sends to the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-fetch"></a><a href="#hello-cpp-fetch"><img src="images/callouts/5.png" alt="5" border="0"></a> </p></td><td valign="top" align="left"><p>Reads the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-acknowledge"></a><a href="#hello-cpp-acknowledge"><img src="images/callouts/6.png" alt="6" border="0"></a> </p></td><td valign="top" align="left"><p>Acknowledges messages that have been read. To guarantee delivery, a message remains on the messaging broker until it is acknowledged by a client. session.acknowledge() acknowledges al
l unacknowledged messages for the given session—this allows acknowledgements to be batched, which is more efficient than acknowledging messages individually.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-close"></a><a href="#hello-cpp-close"><img src="images/callouts/7.png" alt="7" border="0"></a> </p></td><td valign="top" align="left"><p>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</p></td></tr></table></div></div></div><br class="example-break"></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch01.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="ch02s02.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 1. Introduction </td><td width="20%" align="center"><a accesskey="h" hr
ef="index.html">Home</a></td><td width="40%" align="right" valign="top"> 2. A Simple Messaging Program in Python</td></tr></table></div></body></html>
+}</pre><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-open"></a><a href="#hello-cpp-open">(1)</a> </p></td><td valign="top" align="left"><p>Establishes the connection with the messaging broker.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-session"></a><a href="#hello-cpp-session">(2)</a> </p></td><td valign="top" align="left"><p>Creates a session object, which maintains the state of all interactions with the messaging broker, and manages senders and receivers.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-receiver"></a><a href="#hello-cpp-receiver">(3)</a> </p></td><td valign="top" align="left"><p>Creates a receiver that reads from the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-sender"></a><a href="#hello-cpp-sender">(4)</a> </p></td><td valign="top" align="left">
<p>Creates a sender that sends to the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-fetch"></a><a href="#hello-cpp-fetch">(5)</a> </p></td><td valign="top" align="left"><p>Reads the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-acknowledge"></a><a href="#hello-cpp-acknowledge">(6)</a> </p></td><td valign="top" align="left"><p>Acknowledges messages that have been read. To guarantee delivery, a message remains on the messaging broker until it is acknowledged by a client. session.acknowledge() acknowledges all unacknowledged messages for the given session—this allows acknowledgements to be batched, which is more efficient than acknowledging messages individually.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-cpp-close"></a><a href="#hello-cpp-close">(7)</a> <
/p></td><td valign="top" align="left"><p>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</p></td></tr></table></div></div></div><br class="example-break"></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch01.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="ch02s02.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 1. Introduction </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 2. A Simple Messaging Program in Python</td></tr></table></div></body></html>
Modified: qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02s02.html
URL: http://svn.apache.org/viewvc/qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02s02.html?rev=955411&r1=955410&r2=955411&view=diff
==============================================================================
--- qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02s02.html (original)
+++ qpid/site/docs/books/0.5/Programming-In-Apache-Qpid/html/ch02s02.html Wed Jun 16 22:01:44 2010
@@ -1,6 +1,6 @@
-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>2. A Simple Messaging Program in Python</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="prev" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="next" href="ch02s03.html" title="3. Addresses"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">2. A Simple Messaging Program in Python</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch02.html">Prev</a> </td><th width="60%" align="center">Chapter 2. Using the Qpid Messaging API</th><td width="20%" align="right"> <a accesskey="n" href="ch02s03.html">Next</a></td></tr
></table><hr></div><div class="section" title="2. A Simple Messaging Program in Python"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2621571"></a>2. A Simple Messaging Program in Python</h2></div></div></div><p>The following Python program shows how to create a
+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>2. A Simple Messaging Program in Python</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="prev" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="next" href="ch02s03.html" title="3. A Simple Messaging Program in .NET C#"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">2. A Simple Messaging Program in Python</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch02.html">Prev</a> </td><th width="60%" align="center">Chapter 2. Using the Qpid Messaging API</th><td width="20%" align="right"> <a accesskey="n" href="ch0
2s03.html">Next</a></td></tr></table><hr></div><div class="section" title="2. A Simple Messaging Program in Python"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2764277"></a>2. A Simple Messaging Program in Python</h2></div></div></div><p>The following Python program shows how to create a
connection, create a session, send messages using a sender, and
- receive messages using a receiver.</p><div class="example"><a name="id2599690"></a><p class="title"><b>Example 2.2. "Hello world!" in Python</b></p><div class="example-contents"><pre lang="python" class="programlisting">
+ receive messages using a receiver.</p><div class="example"><a name="id2747068"></a><p class="title"><b>Example 2.2. "Hello world!" in Python</b></p><div class="example-contents"><pre lang="python" class="programlisting">
import sys
from qpid.messaging import *
@@ -10,20 +10,20 @@ address = "amq.topic" if len(sys.argv)&l
connection = Connection(broker)
try:
- connection.open() <a class="co" name="hello-python-open" href="ch02s02.html#callout-python-open"><img src="images/callouts/1.png" alt="1" border="0"></a>
- session = connection.session() <a class="co" name="hello-python-session" href="ch02s02.html#callout-python-session"><img src="images/callouts/2.png" alt="2" border="0"></a>
+ connection.open() <a class="co" name="hello-python-open" href="ch02s02.html#callout-python-open">(1)</a>
+ session = connection.session() <a class="co" name="hello-python-session" href="ch02s02.html#callout-python-session">(2)</a>
- sender = session.sender(address) <a class="co" name="hello-python-sender" href="ch02s02.html#callout-python-sender"><img src="images/callouts/3.png" alt="3" border="0"></a>
- receiver = session.receiver(address) <a class="co" name="hello-python-receiver" href="ch02s02.html#callout-python-receiver"><img src="images/callouts/4.png" alt="4" border="0"></a>
+ sender = session.sender(address) <a class="co" name="hello-python-sender" href="ch02s02.html#callout-python-sender">(3)</a>
+ receiver = session.receiver(address) <a class="co" name="hello-python-receiver" href="ch02s02.html#callout-python-receiver">(4)</a>
sender.send(Message("Hello world!"));
- message = receiver.fetch(timeout=1) <a class="co" name="hello-python-fetch" href="ch02s02.html#callout-python-fetch"><img src="images/callouts/5.png" alt="5" border="0"></a>
+ message = receiver.fetch(timeout=1) <a class="co" name="hello-python-fetch" href="ch02s02.html#callout-python-fetch">(5)</a>
print message.content
- session.acknowledge() <a class="co" name="hello-python-acknowledge" href="ch02s02.html#callout-python-acknowledge"><img src="images/callouts/6.png" alt="6" border="0"></a>
+ session.acknowledge() <a class="co" name="hello-python-acknowledge" href="ch02s02.html#callout-python-acknowledge">(6)</a>
except MessagingError,m:
print m
finally:
- connection.close() <a class="co" name="hello-python-close" href="ch02s02.html#callout-python-close"><img src="images/callouts/7.png" alt="7" border="0"></a>
-</pre><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-open"></a><a href="#hello-python-open"><img src="images/callouts/1.png" alt="1" border="0"></a> </p></td><td valign="top" align="left"><p>Establishes the connection with the messaging broker.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-session"></a><a href="#hello-python-session"><img src="images/callouts/2.png" alt="2" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a session object, which maintains the state of all interactions with the messaging broker, and manages senders and receivers.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-receiver"></a><a href="#hello-python-receiver"><img src="images/callouts/4.png" alt="4" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a receiver that reads from the given address.</p></
td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-sender"></a><a href="#hello-python-sender"><img src="images/callouts/3.png" alt="3" border="0"></a> </p></td><td valign="top" align="left"><p>Creates a sender that sends to the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-fetch"></a><a href="#hello-python-fetch"><img src="images/callouts/5.png" alt="5" border="0"></a> </p></td><td valign="top" align="left"><p>Reads the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-acknowledge"></a><a href="#hello-python-acknowledge"><img src="images/callouts/6.png" alt="6" border="0"></a> </p></td><td valign="top" align="left"><p>Acknowledges messages that have been read. To guarantee delivery, a message remains on the messaging broker until it is acknowledged by a client. se
ssion.acknowledge() acknowledges all unacknowledged messages for the given session—this allows acknowledgements to be batched, which is more efficient than acknowledging messages individually.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-close"></a><a href="#hello-python-close"><img src="images/callouts/7.png" alt="7" border="0"></a> </p></td><td valign="top" align="left"><p>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</p></td></tr></table></div></div></div><br class="example-break"></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch02.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch02s03.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter
2. Using the Qpid Messaging API </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 3. Addresses</td></tr></table></div></body></html>
+ connection.close() <a class="co" name="hello-python-close" href="ch02s02.html#callout-python-close">(7)</a>
+</pre><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-open"></a><a href="#hello-python-open">(1)</a> </p></td><td valign="top" align="left"><p>Establishes the connection with the messaging broker.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-session"></a><a href="#hello-python-session">(2)</a> </p></td><td valign="top" align="left"><p>Creates a session object, which maintains the state of all interactions with the messaging broker, and manages senders and receivers.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-receiver"></a><a href="#hello-python-receiver">(4)</a> </p></td><td valign="top" align="left"><p>Creates a receiver that reads from the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-sender"></a><a href="#hello-python-sender">(3)</a> </p></td><td val
ign="top" align="left"><p>Creates a sender that sends to the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-fetch"></a><a href="#hello-python-fetch">(5)</a> </p></td><td valign="top" align="left"><p>Reads the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-acknowledge"></a><a href="#hello-python-acknowledge">(6)</a> </p></td><td valign="top" align="left"><p>Acknowledges messages that have been read. To guarantee delivery, a message remains on the messaging broker until it is acknowledged by a client. session.acknowledge() acknowledges all unacknowledged messages for the given session—this allows acknowledgements to be batched, which is more efficient than acknowledging messages individually.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-python-close"></
a><a href="#hello-python-close">(7)</a> </p></td><td valign="top" align="left"><p>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</p></td></tr></table></div></div></div><br class="example-break"></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch02.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch02s03.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 2. Using the Qpid Messaging API </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 3. A Simple Messaging Program in .NET C#</td></tr></table></div></body></html>
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@@ -1,565 +1,39 @@
-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>3. Addresses</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="prev" href="ch02s02.html" title="2. A Simple Messaging Program in Python"><link rel="next" href="ch02s04.html" title="4. Logging"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">3. Addresses</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch02s02.html">Prev</a> </td><th width="60%" align="center">Chapter 2. Using the Qpid Messaging API</th><td width="20%" align="right"> <a accesskey="n" href="ch02s04.html">Next</a></td></tr></table><hr></div><div class="section" title="3.
Addresses"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="section-addresses"></a>3. Addresses</h2></div></div></div><p>An <em class="firstterm">address</em> is the name of a message
- target or message source. In the programs we have just seen, we
- used the address <code class="literal">amq.topic</code> (which is the name
- of an exchange on an AMQP 0-10 messaging broker).
-
- The methods that create senders and receivers require an
- address. The details of sending to a particular target or
- receiving from a particular source are then handled by the
- sender or receiver. A different target or source can be used
- simply by using a different address.
- </p><p>An address resolves to a <em class="firstterm">node</em>. The
- Qpid Messaging API recognises two kinds of nodes,
- <em class="firstterm">queues</em> and <em class="firstterm">topics</em>
-
- <sup>[<a name="id2609913" href="#ftn.id2609913" class="footnote">1</a>]</sup>.
-
- A queue stores each message until it has been received and
- acknowledged, and only one receiver can receive a given message
- <sup>[<a name="id2621138" href="#ftn.id2621138" class="footnote">2</a>]</sup>
-
- A topic immediately delivers a message to all eligible
- receivers; if there are no eligible receivers, it discards the
- message. In the AMQP 0-10 implementation of the API,
-
- <sup>[<a name="id2614455" href="#ftn.id2614455" class="footnote">3</a>]</sup>
-
- queues map to AMQP queues, and topics map to AMQP exchanges.
-
- <sup>[<a name="id2598385" href="#ftn.id2598385" class="footnote">4</a>]</sup>
- </p><p>In the rest of this tutorial, we present many examples
- using two programs that take an address as a command line
- parameter. <span class="command"><strong>spout</strong></span> sends messages to the
- target address, <span class="command"><strong>drain</strong></span> receives messages from
- the source address. The source code is available in both C++
- and Python, and can be found in the examples directory for each
- language. These programs can use any address string as a source
- or a destination, and have many command line options to
- configure behavior—use the <span class="command"><strong>-h</strong></span> option
- for documentation on these options.
-
- <sup>[<a name="id2589472" href="#ftn.id2589472" class="footnote">5</a>]</sup>
-
-
- The examples in this tutorial also use the
- <span class="command"><strong>qpid-config</strong></span> utility to configure AMQP 0-10
- queues and exchanges on a Qpid broker.
- </p><div class="example"><a name="id2617058"></a><p class="title"><b>Example 2.3. Queues</b></p><div class="example-contents"><p>Create a queue with <span class="command"><strong>qpid-config</strong></span>, send a message using
- <span class="command"><strong>spout</strong></span>, and read it using <span class="command"><strong>drain</strong></span>:</p><pre class="screen">
-$ qpid-config add queue hello-world
-$ ./spout hello-world
-$ ./drain hello-world
-
-Message(properties={spout-id:c877e622-d57b-4df2-bf3e-6014c68da0ea:0}, content='')
- </pre><p>The queue stored the message sent by <span class="command"><strong>spout</strong></span> and delivered
- it to <span class="command"><strong>drain</strong></span> when requested.</p><p>Once the message has been delivered and and acknowledged
- by <span class="command"><strong>drain</strong></span>, it is no longer available on the queue. If we run
- <span class="command"><strong>drain</strong></span> one more time, no messages will be retrieved.</p><pre class="screen">
-$ ./drain hello-world
-$
- </pre></div></div><br class="example-break"><div class="example"><a name="id2613118"></a><p class="title"><b>Example 2.4. Topics</b></p><div class="example-contents"><p>This example is similar to the previous example, but it
- uses a topic instead of a queue.</p><p>First, use <span class="command"><strong>qpid-config</strong></span> to remove the queue
- and create an exchange with the same name:</p><pre class="screen">
-$ qpid-config del queue hello-world
-$ qpid-config add exchange topic hello-world
- </pre><p>Now run <span class="command"><strong>drain</strong></span> and <span class="command"><strong>spout</strong></span> the same way we did in the previous example:</p><pre class="screen">
-$ ./spout hello-world
-$ ./drain hello-world
-$
- </pre><p>Topics deliver messages immediately to any interested
- receiver, and do not store messages. Because there were no
- receivers at the time <span class="command"><strong>spout</strong></span> sent the
- message, it was simply discarded. When we ran
- <span class="command"><strong>drain</strong></span>, there were no messages to
- receive.</p><p>Now let's run <span class="command"><strong>drain</strong></span> first, using the
- <code class="literal">-t</code> option to specify a timeout in seconds.
- While <span class="command"><strong>drain</strong></span> is waiting for messages,
- run <span class="command"><strong>spout</strong></span> in another window.</p><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">
-$ ./drain -t 30 hello-word
- </pre><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">
-$ ./spout hello-word
- </pre><p>Once <span class="command"><strong>spout</strong></span> has sent a message, return
- to the first window to see the output from
- <span class="command"><strong>drain</strong></span>:</p><pre class="screen">
-Message(properties={spout-id:7da2d27d-93e6-4803-8a61-536d87b8d93f:0}, content='')
- </pre><p>You can run <span class="command"><strong>drain</strong></span> in several separate
- windows; each creates a subscription for the exchange, and
- each receives all messages sent to the exchange.</p></div></div><br class="example-break"><div class="section" title="3.1. Address Strings"><div class="titlepage"><div><div><h3 class="title"><a name="id2598210"></a>3.1. Address Strings</h3></div></div></div><p>So far, our examples have used address strings that
- contain only the name of a node. An <em class="firstterm">address
- string</em> can also contain a
- <em class="firstterm">subject</em> and
- <em class="firstterm">options</em>.</p><p>The syntax for an address string is:</p><pre class="programlisting">
-address_string ::= <address> [ / <subject> ] [ ; <options> ]
-options ::= { <key> : <value>, ... }
-</pre><p>Addresses, subjects, and keys are strings. Values can
- be numbers, strings (with optional single or double quotes),
- maps, or lists. A complete BNF for address strings appears in
- <a class="xref" href="ch02s03.html#section-address-string-bnf" title="3.4. Address String Grammar">Section 3.4, “Address String Grammar”</a>.</p><p>So far, the address strings in this tutorial have used
- only addresses. The following sections show how to use
- subjects and options.</p></div><div class="section" title="3.2. Subjects"><div class="titlepage"><div><div><h3 class="title"><a name="id2607393"></a>3.2. Subjects</h3></div></div></div><p>Every message has a property called
- <em class="firstterm">subject</em>, which is analogous to the
- subject on an email message. If no subject is specified, the
- message's subject is null. For convenience, address strings
- also allow a subject. If a sender's address contains a
- subject, it is used as the default subject for the messages
- it sends.
-
- If a receiver's address contains a subject, it is used to
- select only messages that match the subject—the matching
- algorithm depends on the message source.
- </p><p>
- In AMQP 0-10, each exchange type has its own matching
- algorithm, and queues do not provide filtering. This is
- discussed in <a class="xref" href="ch02s12.html" title="12. The AMQP 0-10 mapping">Section 12, “The AMQP 0-10 mapping”</a>.
- </p><div class="note" title="Note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>
- Currently, a receiver bound to a queue ignores subjects,
- receiving messages from the queue without filtering.
-
- In the future, if a receiver is bound to a queue, and its
- address contains a subject, the subject will be used as a
- selector to filter messages.
- </p></div><div class="example"><a name="id2606918"></a><p class="title"><b>Example 2.5. Using subjects</b></p><div class="example-contents"><p>In this example we show how subjects affect message
- flow.</p><p>First, let's use <span class="command"><strong>qpid-config</strong></span> to create a topic exchange.</p><pre class="screen">
-$ qpid-config add exchange topic news-service
- </pre><p>Now we use drain to receive messages from <code class="literal">news-service</code> that match the subject <code class="literal">sports</code>.</p><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">
-$ ./drain -t 30 news-service/sports
- </pre><p>In a second window, let's send messages to <code class="literal">news-service</code> using two different subjects:</p><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">
-$ ./spout news-service/sports
-$ ./spout news-service/news
- </pre><p>Now look at the first window, the message with the
- subject <code class="literal">sports</code> has been received, but not
- the message with the subject <code class="literal">news</code>:</p><pre class="screen">
-Message(properties={qpid.subject:sports, spout-id:9441674e-a157-4780-a78e-f7ccea998291:0}, content='')
- </pre><p>If you run <span class="command"><strong>drain</strong></span> in multiple
- windows using the same subject, all instances of
- <span class="command"><strong>drain</strong></span> receive the messages for that
- subject.</p></div></div><br class="example-break"><p>The AMQP exchange type we are using here,
- <code class="literal">amq.topic</code>, can also do more sophisticated
- matching.
-
- A sender's subject can contain multiple words separated by a
- <span class="quote">“<span class="quote">.</span>”</span> delimiter. For instance, in a news
- application, the sender might use subjects like
- <code class="literal">usa.news</code>, <code class="literal">usa.weather</code>,
- <code class="literal">europe.news</code>, or
- <code class="literal">europe.weather</code>.
-
- The receiver's subject can include wildcard characters—
- <span class="quote">“<span class="quote">#</span>”</span> matches one or more words in the message's
- subject, <span class="quote">“<span class="quote">*</span>”</span> matches a single word.
-
- For instance, if the subject in the source address is
- <code class="literal">*.news</code>, it matches messages with the
- subject <code class="literal">europe.news</code> or
- <code class="literal">usa.news</code>; if it is
- <code class="literal">europe.#</code>, it matches messages with subjects
- like <code class="literal">europe.news</code> or
- <code class="literal">europe.pseudo.news</code>.</p><div class="example"><a name="id2599695"></a><p class="title"><b>Example 2.6. Subjects with multi-word keys</b></p><div class="example-contents"><p>This example uses drain and spout to demonstrate the
- use of subjects with two-word keys.</p><p>Let's use <span class="command"><strong>drain</strong></span> with the subject
- <code class="literal">*.news</code> to listen for messages in which
- the second word of the key is
- <code class="literal">news</code>.</p><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">
-$ ./drain -t 30 news-service/*.news
- </pre><p>Now let's send messages using several different
- two-word keys:</p><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">
-$ ./spout news-service/usa.news
-$ ./spout news-service/usa.sports
-$ ./spout news-service/europe.sports
-$ ./spout news-service/europe.news
- </pre><p>In the first window, the messages with
- <code class="literal">news</code> in the second word of the key have
- been received:</p><pre class="screen">
-Message(properties={qpid.subject:usa.news, spout-id:73fc8058-5af6-407c-9166-b49a9076097a:0}, content='')
-Message(properties={qpid.subject:europe.news, spout-id:f72815aa-7be4-4944-99fd-c64c9747a876:0}, content='')
- </pre><p>Next, let's use <span class="command"><strong>drain</strong></span> with the
- subject <code class="literal">#.news</code> to match any sequence of
- words that ends with <code class="literal">news</code>.</p><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">
-$ ./drain -t 30 news-service/#.news
- </pre><p>In the second window, let's send messages using a
- variety of different multi-word keys:</p><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">
-$ ./spout news-service/news
-$ ./spout news-service/sports
-$ ./spout news-service/usa.news
-$ ./spout news-service/usa.sports
-$ ./spout news-service/usa.faux.news
-$ ./spout news-service/usa.faux.sports
- </pre><p>In the first window, messages with
- <code class="literal">news</code> in the last word of the key have been
- received:</p><pre class="screen">
-Message(properties={qpid.subject:news, spout-id:cbd42b0f-c87b-4088-8206-26d7627c9640:0}, content='')
-Message(properties={qpid.subject:usa.news, spout-id:234a78d7-daeb-4826-90e1-1c6540781eac:0}, content='')
-Message(properties={qpid.subject:usa.faux.news, spout-id:6029430a-cfcb-4700-8e9b-cbe4a81fca5f:0}, content='')
- </pre></div></div><br class="example-break"></div><div class="section" title="3.3. Address String Options"><div class="titlepage"><div><div><h3 class="title"><a name="id2594787"></a>3.3. Address String Options</h3></div></div></div><p>
- The options in an address string contain additional
- information for the senders or receivers created for it,
- including:
- </p><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"><p>
- Policies for assertions about the node to which an address
- refers.
- </p><p>
- For instance, in the address string <code class="literal">my-queue;
- {assert: always, node:{ type: queue }}</code>, the node
- named <code class="literal">my-queue</code> must be a queue; if not,
- the address does not resolve to a node, and an exception
- is raised.
- </p></li><li class="listitem"><p>
- Policies for automatically creating or deleting the node to which an address refers.
- </p><p>
- For instance, in the address string <code class="literal">xoxox ; {create: always}</code>,
- the queue <code class="literal">xoxox</code> is created, if it does
- not exist, before the address is resolved.
- </p></li><li class="listitem"><p>
- Extension points that can be used for sender/receiver configuration.
- </p><p>
- For instance, if the address for a receiver is
- <code class="literal">my-queue; {mode: browse}</code>, the receiver
- works in <code class="literal">browse</code> mode, leaving messages
- on the queue so other receivers can receive them.
- </p></li><li class="listitem"><p>
- Extension points that rely on the functionality of specific node types.
- </p><p>
- For instance, the Qpid XML exchange can use XQuery to do
- content-based routing for XML messages, or to query
- message data using XQuery. Queries can be specified using
- options.
- </p></li></ul></div><p>
- Let's use some examples to show how these different kinds of
- address string options affect the behavior of senders and
- receives.
- </p><div class="section" title="3.3.1. assert"><div class="titlepage"><div><div><h4 class="title"><a name="id2610235"></a>3.3.1. assert</h4></div></div></div><p>
- In this section, we use the <code class="literal">assert</code> option
- to ensure that the address resolves to a node of the required
- type.
- </p><div class="example"><a name="id2576196"></a><p class="title"><b>Example 2.7. Assertions on Nodes</b></p><div class="example-contents"><p>Let's use <span class="command"><strong>qpid-config</strong></span> to create a
- queue and a topic.</p><pre class="screen">
-$ qpid-config add queue my-queue
-$ qpid-config add exchange topic my-topic
- </pre><p>
- We can now use the address specified to drain to assert that it is
- of a particular type:
- </p><pre class="screen">
-$ ./drain 'my-queue; {assert: always, node:{ type: queue }}'
-$ ./drain 'my-queue; {assert: always, node:{ type: topic }}'
-2010-04-20 17:30:46 warning Exception received from broker: not-found: not-found: Exchange not found: my-queue (../../src/qpid/broker/ExchangeRegistry.cpp:92) [caused by 2 \x07:\x01]
-Exchange my-queue does not exist
- </pre><p>
- The first attempt passed without error as my-queue is indeed a
- queue. The second attempt however failed; my-queue is not a
- topic.
- </p><p>
- We can do the same thing for my-topic:
- </p><pre class="screen">
-$ ./drain 'my-topic; {assert: always, node:{ type: topic }}'
-$ ./drain 'my-topic; {assert: always, node:{ type: queue }}'
-2010-04-20 17:31:01 warning Exception received from broker: not-found: not-found: Queue not found: my-topic (../../src/qpid/broker/SessionAdapter.cpp:754) [caused by 1 \x08:\x01]
-Queue my-topic does not exist
- </pre></div></div><br class="example-break"><p>Now let's use the <code class="literal">create</code> option to
- create the queue <code class="literal">xoxox</code> if it does not already
- exist:</p></div><div class="section" title="3.3.2. create"><div class="titlepage"><div><div><h4 class="title"><a name="id2593763"></a>3.3.2. create</h4></div></div></div><p>In previous examples, we created the queue before
- listening for messages on it. Using <code class="literal">create:
- always</code>, the queue is automatically created if it
- does not exist.</p><div class="example"><a name="id2616221"></a><p class="title"><b>Example 2.8. Creating a Queue Automatically</b></p><div class="example-contents"><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">$ ./drain -t 30 "xoxox ; {create: always}"</pre><p>Now we can send messages to this queue:</p><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">$ ./spout "xoxox ; {create: always}"</pre><p>Returning to the first window, we see that <span class="command"><strong>drain</strong></span> has received this message:</p><pre class="screen">Message(properties={spout-id:1a1a3842-1a8b-4f88-8940-b4096e615a7d:0}, content='')</pre></div></div><br class="example-break"></div><div class="section" title="3.3.3. browse"><div class="titlepage"><div><div><h4 class="title"><a name="id2597449"></a>3.3.3. browse</h4></div></div></div><p>Some options specify message transfer semantics; for
- instance, they may state whether messages should be consumed or
- read in browsing mode, or specify reliability
- characteristics. The following example uses the
- <code class="literal">browse</code> option to receive messages without
- removing them from a queue.</p><div class="example"><a name="id2600049"></a><p class="title"><b>Example 2.9. Browsing a Queue</b></p><div class="example-contents"><p>
- Let's use the browse mode to receive messages without
- removing them from the queue. First we send three messages to the
- queue:
- </p><pre class="screen">
-$ ./spout my-queue --content one
-$ ./spout my-queue --content two
-$ ./spout my-queue --content three
- </pre><p>Now we use drain to get those messages, using the browse option:</p><pre class="screen">
-$ ./drain 'my-queue; {mode: browse}'
-Message(properties={spout-id:fbb93f30-0e82-4b6d-8c1d-be60eb132530:0}, content='one')
-Message(properties={spout-id:ab9e7c31-19b0-4455-8976-34abe83edc5f:0}, content='two')
-Message(properties={spout-id:ea75d64d-ea37-47f9-96a9-d38e01c97925:0}, content='three')
- </pre><p>We can confirm the messages are still on the queue by repeating the drain:</p><pre class="screen">
-$ ./drain 'my-queue; {mode: browse}'
-Message(properties={spout-id:fbb93f30-0e82-4b6d-8c1d-be60eb132530:0}, content='one')
-Message(properties={spout-id:ab9e7c31-19b0-4455-8976-34abe83edc5f:0}, content='two')
-Message(properties={spout-id:ea75d64d-ea37-47f9-96a9-d38e01c97925:0}, content='three')
- </pre></div></div><br class="example-break"></div><div class="section" title="3.3.4. x-bindings"><div class="titlepage"><div><div><h4 class="title"><a name="id2591003"></a>3.3.4. x-bindings</h4></div></div></div><p><code class="literal">x-bindings</code> allows an address string
- to specify properties AMQP 0-10 bindings. For instance, the
- XML Exchange is an AMQP 0-10 custom exchange provided by the
- Apache Qpid C++ broker. It allows messages to be filtered
- using XQuery; queries can address either message properties or
- XML content in the body of the message. These queries can be
- specified in addresses using x-bindings</p><p>An instance of the XML Exchange must be added before it
- can be used:</p><pre class="programlisting">
-$ qpid-config add exchange xml xml
- </pre><p>When using the XML Exchange, a receiver provides an
- XQuery as an x-binding argument. If the query contains a
- context item (a path starting with <span class="quote">“<span class="quote">.</span>”</span>), then it
- is applied to the content of the message, which must be
- well-formed XML. For instance, <code class="literal">./weather</code> is
- a valid XQuery, which matches any message in which the root
- element is named <code class="literal">weather</code>. Here is an
- address string that contains this query:</p><pre class="programlisting">
-xml; {
- link: {
- x-bindings: [{exchange:xml, key:weather, arguments:{xquery:"./weather"} }]
- }
+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>3. A Simple Messaging Program in .NET C#</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2"><link rel="home" href="index.html" title="Programming in Apache Qpid"><link rel="up" href="ch02.html" title="Chapter 2. Using the Qpid Messaging API"><link rel="prev" href="ch02s02.html" title="2. A Simple Messaging Program in Python"><link rel="next" href="ch02s04.html" title="4. Addresses"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">3. A Simple Messaging Program in .NET C#</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch02s02.html">Prev</a> </td><th width="60%" align="center">Chapter 2. Using the Qpid Messaging API</th><td width="20%" align="right"> <a accesskey="n" href="ch02s04.html">Next</a></
td></tr></table><hr></div><div class="section" title="3. A Simple Messaging Program in .NET C#"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2778332"></a>3. A Simple Messaging Program in .NET C#</h2></div></div></div><p>The following .NET C# program shows how to create a connection,
+ create a session, send messages using a sender, and receive
+ messages using a receiver.</p><div class="example"><a name="id2783534"></a><p class="title"><b>Example 2.3. "Hello world!" in .NET C#</b></p><div class="example-contents"><pre lang="c++" class="programlisting">
+using System;
+using Org.Apache.Qpid.Messaging; <a class="co" name="hello-csharp-using" href="ch02s03.html#callout-csharp-using">(1)</a>
+
+namespace Org.Apache.Qpid.Messaging {
+ class Program {
+ static void Main(string[] args) {
+ String broker = args.Length > 0 ? args[0] : "localhost:5672";
+ String address = args.Length > 1 ? args[1] : "amq.topic";
+
+ Connection connection = null;
+ try {
+ connection = new Connection(broker);
+ connection.Open(); <a class="co" name="hello-csharp-open" href="ch02s03.html#callout-csharp-open">(2)</a>
+ Session session = connection.CreateSession(); <a class="co" name="hello-csharp-session" href="ch02s03.html#callout-csharp-session">(3)</a>
+
+ Receiver receiver = session.CreateReceiver(address); <a class="co" name="hello-csharp-receiver" href="ch02s03.html#callout-csharp-receiver">(4)</a>
+ Sender sender = session.CreateSender(address); <a class="co" name="hello-csharp-sender" href="ch02s03.html#callout-csharp-sender">(5)</a>
+
+ sender.Send(new Message("Hello world!"));
+
+ Message message = new Message();
+ message = receiver.Fetch(DurationConstants.SECOND * 1); <a class="co" name="hello-csharp-fetch" href="ch02s03.html#callout-csharp-fetch">(6)</a>
+ Console.WriteLine("{0}", message.GetContent());
+ session.Acknowledge(); <a class="co" name="hello-csharp-acknowledge" href="ch02s03.html#callout-csharp-acknowledge">(7)</a>
+
+ connection.Close(); <a class="co" name="hello-csharp-close" href="ch02s03.html#callout-csharp-close">(8)</a>
+ } catch (Exception e) {
+ Console.WriteLine("Exception {0}.", e);
+ if (null != connection)
+ connection.Close();
+ }
+ }
+ }
}
- </pre><p>When using longer queries with <span class="command"><strong>drain</strong></span>,
- it is often useful to place the query in a file, and use
- <span class="command"><strong>cat</strong></span> in the command line. We do this in the
- following example.</p><div class="example"><a name="id2583051"></a><p class="title"><b>Example 2.10. Using the XML Exchange</b></p><div class="example-contents"><p>This example uses an x-binding that contains queries, which filter based on the content of XML messages. Here is an XQuery that we will use in this example:</p><pre class="programlisting">
-
-let $w := ./weather
-return $w/station = 'Raleigh-Durham International Airport (KRDU)'
- and $w/temperature_f > 50
- and $w/temperature_f - $w/dewpoint > 5
- and $w/wind_speed_mph > 7
- and $w/wind_speed_mph < 20
- </pre><p>We can specify this query in an x-binding to listen to messages that meet the criteria specified by the query:</p><p><span class="emphasis"><em>First Window:</em></span></p><pre class="screen">
-$ ./drain -f "xml; {link:{x-bindings:[{key:'weather',
-arguments:{xquery:\"$(cat rdu.xquery )\"}}]}}"
- </pre><p>In another window, let's create an XML message that meets the criteria in the query, and place it in the file <code class="filename">rdu.xml</code>:</p><pre class="programlisting">
-<weather>
- <station>Raleigh-Durham International Airport (KRDU)</station>
- <wind_speed_mph>16</wind_speed_mph>
- <temperature_f>70</temperature_f>
- <dewpoint>35</dewpoint>
-</weather>
- </pre><p>Now let's use <span class="command"><strong>spout</strong></span> to send this message to the XML exchange:</p><p><span class="emphasis"><em>Second Window:</em></span></p><pre class="screen">
-spout --content "$(cat rdu.xml)" xml/weather
- </pre><p>Returning to the first window, we see that the message has been received:</p><pre class="screen">$ ./drain -f "xml; {link:{x-bindings:[{exchange:'xml', key:'weather', arguments:{xquery:\"$(cat rdu.xquery )\"}}]}}"
-Message(properties={qpid.subject:weather, spout-id:31c431de-593f-4bec-a3dd-29717bd945d3:0},
-content='<weather>
- <station>Raleigh-Durham International Airport (KRDU)</station>
- <wind_speed_mph>16</wind_speed_mph>
- <temperature_f>40</temperature_f>
- <dewpoint>35</dewpoint>
-</weather>')
- </pre></div></div><br class="example-break"></div><div class="section" title="3.3.5. Address String Options - Reference"><div class="titlepage"><div><div><h4 class="title"><a name="id2604667"></a>3.3.5. Address String Options - Reference</h4></div></div></div><div class="table"><a name="id2578819"></a><p class="title"><b>Table 2.1. Address String Options</b></p><div class="table-contents"><table summary="Address String Options" width="100%" border="1"><colgroup><col><col><col></colgroup><thead><tr><th>option</th><th>value</th><th>semantics</th></tr></thead><tbody><tr><td>
- assert
- </td><td>
- one of: always, never, sender or receiver
- </td><td>
- Asserts that the properties specified in the node option
- match whatever the address resolves to. If they do not,
- resolution fails and an exception is raised.
- </td></tr><tr><td>
- create
- </td><td>
- one of: always, never, sender or receiver
- </td><td>
- Creates the node to which an address refers if it does
- not exist. No error is raised if the node does
- exist. The details of the node may be specified in the
- node option.
- </td></tr><tr><td>
- delete
- </td><td>
- one of: always, never, sender or receiver
- </td><td>
- Delete the node when the sender or receiver is closed.
- </td></tr><tr><td>
- node
- </td><td>
- A nested map containing the entries shown in <a class="xref" href="ch02s03.html#table-node-properties" title="Table 2.2. Node Properties">Table 2.2, “Node Properties”</a>.
- </td><td>
- Specifies properties of the node to which the address
- refers. These are used in conjunction with the assert or
- create options.
- </td></tr><tr><td>
- link
- </td><td>
- A nested map containing the entries shown in <a class="xref" href="ch02s03.html#table-link-properties" title="Table 2.3. Link Properties">Table 2.3, “Link Properties”</a>.
- </td><td>
- Used to control the establishment of a conceptual link
- from the client application to or from the target/source
- address.
- </td></tr><tr><td>
- mode
- </td><td>
- one of: browse, consume
- </td><td>
- This option is only of relevance for source addresses
- that resolve to a queue. If browse is specified the
- messages delivered to the receiver are left on the queue
- rather than being removed. If consume is specified the
- normal behaviour applies; messages are removed from teh
- queue once the client acknoweldges their receipt.
- </td></tr></tbody></table></div></div><br class="table-break"><div class="table"><a name="table-node-properties"></a><p class="title"><b>Table 2.2. Node Properties</b></p><div class="table-contents"><table summary="Node Properties" width="100%" border="1"><colgroup><col><col><col></colgroup><thead><tr><th>property</th><th>value</th><th>semantics</th></tr></thead><tbody><tr><td>
- type
- </td><td>
- topic, queue
- </td><td>
- Indicates the type of the node.
- </td></tr><tr><td>
- durable
- </td><td>
- True, False
- </td><td>
- Indicates whether the node survives a loss of
- volatile storage e.g. if the broker is restarted.
- </td></tr><tr><td>
- x-declare
- </td><td>
- A nested map whose values correspond to the valid fields
- on an AMQP 0-10 queue-declare or exchange-declare
- command.
- </td><td>
- These values are used to fine tune the creation or
- assertion process. Note however that they are protocol
- specific.
- </td></tr><tr><td>
- x-bindings
- </td><td>
- A nested list in which each binding is represented by
- a map. The entries of the map for a binding contain
- the fields that describe an AMQP 0-10 binding. Here is
- the format for x-bindings:
-
-<pre class="programlisting">
-[
- {
- exchange: <exchange>,
- queue: <queue>,
- key: <key>,
- arguments: {
- <key_1>: <value_1>,
- ...,
- <key_n>: <value_n> }
- },
- ...
-]
-</pre>
- </td><td>
- In conjunction with the create option, each of these
- bindings is established as the address is resolved. In
- conjunction with the assert option, the existence of
- each of these bindings is verified during
- resolution. Again, these are protocol specific.
- </td></tr></tbody></table></div></div><br class="table-break"><div class="table"><a name="table-link-properties"></a><p class="title"><b>Table 2.3. Link Properties</b></p><div class="table-contents"><table summary="Link Properties" width="100%" border="1"><colgroup><col><col><col></colgroup><thead><tr><th>option</th><th>value</th><th>semantics</th></tr></thead><tbody><tr><td>
- reliability
- </td><td>
- one of: unreliable, at-least-once, at-most-once, exactly-once
- </td><td>
- Reliability indicates the level of reliability that
- the sender or receiver. <code class="literal">unreliable</code>
- and <code class="literal">at-most-once</code> are currently
- treated as synonyms, and allow messages to be lost if
- a broker crashes or the connection to a broker is
- lost. <code class="literal">at-least-once</code> guarantees that
- a message is not lost, but duplicates may be
- received. <code class="literal">exactly-once</code> guarantees
- that a message is not lost, and is delivered precisely
- once.
- </td></tr><tr><td>
- durable
- </td><td>
- True, False
- </td><td>
- Indicates whether the link survives a loss of
- volatile storage e.g. if the broker is restarted.
- </td></tr><tr><td>
- x-declare
- </td><td>
- A nested map whose values correspond to the valid fields
- of an AMQP 0-10 queue-declare command.
- </td><td>
- These values can be used to customise the subscription
- queue in the case of receiving from an exchange. Note
- however that they are protocol specific.
- </td></tr><tr><td>
- x-subscribe
- </td><td>
- A nested map whose values correspond to the valid fields
- of an AMQP 0-10 message-subscribe command.
- </td><td>
- These values can be used to customise the subscription.
- </td></tr><tr><td>
- x-bindings
- </td><td>
- A nested list each of whose entries is a map that may
- contain fields (queue, exchange, key and arguments)
- describing an AMQP 0-10 binding.
- </td><td>
- These bindings are established during resolution
- independent of the create option. They are considered
- logically part of the linking process rather than of
- node creation.
- </td></tr></tbody></table></div></div><br class="table-break"></div></div><div class="section" title="3.4. Address String Grammar"><div class="titlepage"><div><div><h3 class="title"><a name="section-address-string-bnf"></a>3.4. Address String Grammar</h3></div></div></div><p>This section provides a formal grammar for address strings.</p><p title="Tokens"><b>Tokens. </b>The following regular expressions define the tokens used
- to parse address strings:</p><pre class="programlisting">
-LBRACE: \\{
-RBRACE: \\}
-LBRACK: \\[
-RBRACK: \\]
-COLON: :
-SEMI: ;
-SLASH: /
-COMMA: ,
-NUMBER: [+-]?[0-9]*\\.?[0-9]+
-ID: [a-zA-Z_](?:[a-zA-Z0-9_-]*[a-zA-Z0-9_])?
-STRING: "(?:[^\\\\"]|\\\\.)*"|\'(?:[^\\\\\']|\\\\.)*\'
-ESC: \\\\[^ux]|\\\\x[0-9a-fA-F][0-9a-fA-F]|\\\\u[0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F]
-SYM: [.#*%@$^!+-]
-WSPACE: [ \\n\\r\\t]+
-</pre><p title="Grammar"><b>Grammar. </b>The formal grammar for addresses is given below:</p><pre class="programlisting">
-address := name [ "/" subject ] [ ";" options ]
- name := ( part | quoted )+
-subject := ( part | quoted | "/" )*
- quoted := STRING / ESC
- part := LBRACE / RBRACE / COLON / COMMA / NUMBER / ID / SYM
-options := map
- map := "{" ( keyval ( "," keyval )* )? "}"
- keyval "= ID ":" value
- value := NUMBER / STRING / ID / map / list
- list := "[" ( value ( "," value )* )? "]"
- </pre><p title="Address String Options"><b>Address String Options. </b>The address string options map supports the following parameters:</p><pre class="programlisting">
-<name> [ / <subject> ] ; {
- create: always | sender | receiver | never,
- delete: always | sender | receiver | never,
- assert: always | sender | receiver | never,
- mode: browse | consume,
- node: {
- type: queue | topic,
- durable: True | False,
- x-declare: { ... <declare-overrides> ... },
- x-bindings: [<binding_1>, ... <binding_n>]
- },
- link: {
- name: <link-name>,
- durable: True | False,
- reliability: unreliable | at-most-once | at-least-once | exactly-once,
- x-declare: { ... <declare-overrides> ... },
- x-bindings: [<binding_1>, ... <binding_n>],
- x-subscribe: { ... <subscribe-overrides> ... }
- }
-}
-</pre><div class="itemizedlist" title="Create, Delete, and Assert Policies"><p class="title"><b>Create, Delete, and Assert Policies</b></p><p>The create, delete, and assert policies specify who should
- perfom the associated action:</p><ul class="itemizedlist" type="disc"><li class="listitem"><p><span class="emphasis"><em>always</em></span>: the action is performed by any messaging client</p></li><li class="listitem"><p><span class="emphasis"><em>sender</em></span>: the action is only performed by a sender</p></li><li class="listitem"><p><span class="emphasis"><em>receiver</em></span>: the action is only performed by a receiver</p></li><li class="listitem"><p><span class="emphasis"><em>never</em></span>: the action is never performed (this is the default)</p></li></ul></div><div class="itemizedlist" title="Node-Type"><p class="title"><b>Node-Type</b></p><p>The node-type is one of:</p><ul class="itemizedlist" type="disc"><li class="listitem"><p><span class="emphasis"><em>topic</em></span>: in the AMQP 0-10
- mapping, a topic node defaults to the topic exchange, x-declare
- may be used to specify other exchange types</p></li><li class="listitem"><p><span class="emphasis"><em>queue</em></span>: this is the default node-type</p></li></ul></div></div><div class="footnotes"><br><hr width="100" align="left"><div class="footnote"><p><sup>[<a name="ftn.id2609913" href="#id2609913" class="para">1</a>] </sup>The terms <span class="emphasis"><em>queue</em></span> and
- <span class="emphasis"><em>topic</em></span> here were chosen to align with
- their meaning in JMS. These two addressing 'patterns',
- queue and topic, are sometimes refered as point-to-point
- and publish-subscribe. AMQP 0-10 has an exchange type
- called a <span class="emphasis"><em>topic exchange</em></span>. When the term
- <span class="emphasis"><em>topic</em></span> occurs alone, it refers to a
- Messaging API topic, not the topic
- exchange.</p></div><div class="footnote"><p><sup>[<a name="ftn.id2621138" href="#id2621138" class="para">2</a>] </sup>There are exceptions to this rule; for instance,
- a receiver can use <code class="literal">browse</code> mode, which leaves
- messages on the queue for other receivers to
- read.</p></div><div class="footnote"><p><sup>[<a name="ftn.id2614455" href="#id2614455" class="para">3</a>] </sup>The AMQP 0-10 implementation is the only one
- that currently exists.</p></div><div class="footnote"><p><sup>[<a name="ftn.id2598385" href="#id2598385" class="para">4</a>] </sup>In AMQP 0-10, messages are sent to
- exchanges, and read from queues. The Messaging API also
- allows a sender to send messages to a queue; internally,
- Qpid implements this by sending the message to the default
- exchange, with the name of the queue as the routing key. The
- Messaging API also allows a receiver to receive messages
- from a topic; internally, Qpid implements this by setting up
- a private subscription queue for the receiver and binding
- the subscription queue to the exchange that corresponds to
- the topic.</p></div><div class="footnote"><p><sup>[<a name="ftn.id2589472" href="#id2589472" class="para">5</a>] </sup>Currently, the Python and C++
- implementations of <span class="command"><strong>drain</strong></span> and
- <span class="command"><strong>spout</strong></span> have slightly different
- options. This tutorial uses the C++ implementation. The
- options will be reconciled in the near
- future.</p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch02s02.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch02s04.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2. A Simple Messaging Program in Python </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 4. Logging</td></tr></table></div></body></html>
+</pre><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-using"></a><a href="#hello-csharp-using">(1)</a> </p></td><td valign="top" align="left"><p>Selects the Qpid Messaging namespace. A project reference to the Org.Apache.Qpid.Messaging dll defines the Qpid Messaging namespace objects and methods.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-open"></a><a href="#hello-csharp-open">(2)</a> </p></td><td valign="top" align="left"><p>Establishes the connection with the messaging broker.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-session"></a><a href="#hello-csharp-session">(3)</a> </p></td><td valign="top" align="left"><p>Creates a session object, which maintains the state of all interactions with the messaging broker, and manages senders and receivers.</p></td></tr><tr><td width="5%" valign="top" align="left"><
p><a name="callout-csharp-receiver"></a><a href="#hello-csharp-receiver">(4)</a> </p></td><td valign="top" align="left"><p>Creates a receiver that reads from the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-sender"></a><a href="#hello-csharp-sender">(5)</a> </p></td><td valign="top" align="left"><p>Creates a sender that sends to the given address.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-fetch"></a><a href="#hello-csharp-fetch">(6)</a> </p></td><td valign="top" align="left"><p>Reads the next message. The duration is optional, if omitted, will wait indefinitely for the next message.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-acknowledge"></a><a href="#hello-csharp-acknowledge">(7)</a> </p></td><td valign="top" align="left"><p>Acknowledges messages that have been read. To guarantee delivery, a message remains on the messaging broker until
it is acknowledged by a client. session.acknowledge() acknowledges all unacknowledged messages for the given session—this allows acknowledgements to be batched, which is more efficient than acknowledging messages individually.</p></td></tr><tr><td width="5%" valign="top" align="left"><p><a name="callout-csharp-close"></a><a href="#hello-csharp-close">(8)</a> </p></td><td valign="top" align="left"><p>Closes the connection, all sessions managed by the connection, and all senders and receivers managed by each session.</p></td></tr></table></div></div></div><br class="example-break"></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch02s02.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch02s04.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2. A Simple Messagi
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