Author: mahadev
Date: Thu Jan 29 23:29:42 2009
New Revision: 739082
URL: http://svn.apache.org/viewvc?rev=739082&view=rev
Log:
ZOOKEEPER-269. connectionloss- add more documentation to detail. (phunt and
flavio via mahadev)
Modified:
hadoop/zookeeper/trunk/CHANGES.txt
hadoop/zookeeper/trunk/docs/zookeeperProgrammers.html
hadoop/zookeeper/trunk/docs/zookeeperProgrammers.pdf
hadoop/zookeeper/trunk/src/docs/src/documentation/content/xdocs/zookeeperProgrammers.xml
Modified: hadoop/zookeeper/trunk/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hadoop/zookeeper/trunk/CHANGES.txt?rev=739082&r1=739081&r2=739082&view=diff
==============================================================================
--- hadoop/zookeeper/trunk/CHANGES.txt (original)
+++ hadoop/zookeeper/trunk/CHANGES.txt Thu Jan 29 23:29:42 2009
@@ -128,6 +128,9 @@
ZOOKEEPER-253. documentation of DataWatcher state transition is misleading
regarding auto watch reset on reconnect. (phunt via mahadev)
+ ZOOKEEPER-269. connectionloss- add more documentation to detail. (phunt and
+flavio via mahadev)
+
Release 3.0.0 - 2008-10-21
Non-backward compatible changes:
Modified: hadoop/zookeeper/trunk/docs/zookeeperProgrammers.html
URL:
http://svn.apache.org/viewvc/hadoop/zookeeper/trunk/docs/zookeeperProgrammers.html?rev=739082&r1=739081&r2=739082&view=diff
==============================================================================
--- hadoop/zookeeper/trunk/docs/zookeeperProgrammers.html (original)
+++ hadoop/zookeeper/trunk/docs/zookeeperProgrammers.html Thu Jan 29 23:29:42
2009
@@ -780,10 +780,31 @@
still active. The timing of the PING is conservative enough to
ensure reasonable time to detect a dead connection and reconnect
to a new server.</p>
+<p>
+ Once a connection to the server is successfully established
+ (connected) there are basically two cases where the client lib generates
+ connectionloss (the result code in c binding, exception in Java -- see
+ the API documentation for binding specific details) when either a
synchronous or
+ asynchronous operation is performed and one of the following holds:
+ </p>
+<ol>
+
+<li>
+<p>The application calls an operation on a session that is no
+ longer alive/valid</p>
+</li>
+
+<li>
+<p>The ZooKeeper client disconnects from a server when there
+ are pending operations to that server, i.e., there is a pending
asynchronous call.
+ </p>
+</li>
+
+</ol>
</div>
-<a name="N101BB"></a><a name="ch_zkWatches"></a>
+<a name="N101C9"></a><a name="ch_zkWatches"></a>
<h2 class="h3">ZooKeeper Watches</h2>
<div class="section">
<p>All of the read operations in ZooKeeper - <strong>getData()</strong>,
<strong>getChildren()</strong>, and <strong>exists()</strong> - have the option
of setting a watch as a
@@ -860,7 +881,7 @@
general this all occurs transparently. There is one case where a watch
may be missed: a watch for the existance of a znode not yet created will
be missed if the znode is created and deleted while disconnected.</p>
-<a name="N101F1"></a><a name="sc_WatchGuarantees"></a>
+<a name="N101FF"></a><a name="sc_WatchGuarantees"></a>
<h3 class="h4">What ZooKeeper Guarantees about Watches</h3>
<p>With regard to watches, ZooKeeper maintains these
guarantees:</p>
@@ -895,7 +916,7 @@
</li>
</ul>
-<a name="N10216"></a><a name="sc_WatchRememberThese"></a>
+<a name="N10224"></a><a name="sc_WatchRememberThese"></a>
<h3 class="h4">Things to Remember about Watches</h3>
<ul>
@@ -954,7 +975,7 @@
</div>
-<a name="N10242"></a><a name="sc_ZooKeeperAccessControl"></a>
+<a name="N10250"></a><a name="sc_ZooKeeperAccessControl"></a>
<h2 class="h3">ZooKeeper access control using ACLs</h2>
<div class="section">
<p>ZooKeeper uses ACLs to control access to its znodes (the
@@ -983,7 +1004,7 @@
example, the pair <em>(ip:19.22.0.0/16, READ)</em>
gives the <em>READ</em> permission to any clients with
an IP address that starts with 19.22.</p>
-<a name="N10269"></a><a name="sc_ACLPermissions"></a>
+<a name="N10277"></a><a name="sc_ACLPermissions"></a>
<h3 class="h4">ACL Permissions</h3>
<p>ZooKeeper supports the following permissions:</p>
<ul>
@@ -1039,7 +1060,7 @@
node, but nothing more. (The problem is, if you want to call
zoo_exists() on a node that doesn't exist, there is no
permission to check.)</p>
-<a name="N102BF"></a><a name="sc_BuiltinACLSchemes"></a>
+<a name="N102CD"></a><a name="sc_BuiltinACLSchemes"></a>
<h4>Builtin ACL Schemes</h4>
<p>ZooKeeeper has the following built in schemes:</p>
<ul>
@@ -1100,7 +1121,7 @@
</ul>
-<a name="N10315"></a><a name="ZooKeeper+C+client+API"></a>
+<a name="N10323"></a><a name="ZooKeeper+C+client+API"></a>
<h4>ZooKeeper C client API</h4>
<p>The following constants are provided by the ZooKeeper C
library:</p>
@@ -1322,7 +1343,7 @@
</div>
-<a name="N1042C"></a><a name="ch_zkGuarantees"></a>
+<a name="N1043A"></a><a name="ch_zkGuarantees"></a>
<h2 class="h3">Consistency Guarantees</h2>
<div class="section">
<p>ZooKeeper is a high performance, scalable service. Both reads and
@@ -1448,12 +1469,12 @@
</div>
-<a name="N10493"></a><a name="ch_bindings"></a>
+<a name="N104A1"></a><a name="ch_bindings"></a>
<h2 class="h3">Bindings</h2>
<div class="section">
<p>The ZooKeeper client libraries come in two languages: Java and C.
The following sections describe these.</p>
-<a name="N1049C"></a><a name="Java+Binding"></a>
+<a name="N104AA"></a><a name="Java+Binding"></a>
<h3 class="h4">Java Binding</h3>
<p>There are two packages that make up the ZooKeeper Java binding:
<strong>org.apache.zookeeper</strong> and
<strong>org.apache.zookeeper.data</strong>. The rest of the
@@ -1520,7 +1541,7 @@
(SESSION_EXPIRED and AUTH_FAILED), the ZooKeeper object becomes invalid,
the two threads shut down, and any further ZooKeeper calls throw
errors.</p>
-<a name="N104E5"></a><a name="C+Binding"></a>
+<a name="N104F3"></a><a name="C+Binding"></a>
<h3 class="h4">C Binding</h3>
<p>The C binding has a single-threaded and multi-threaded library.
The multi-threaded library is easiest to use and is most similar to the
@@ -1537,7 +1558,7 @@
(i.e. FreeBSD 4.x). In all other cases, application developers should
link with zookeeper_mt, as it includes support for both Sync and Async
API.</p>
-<a name="N104F4"></a><a name="Installation"></a>
+<a name="N10502"></a><a name="Installation"></a>
<h4>Installation</h4>
<p>If you're building the client from a check-out from the Apache
repository, follow the steps outlined below. If you're building from a
@@ -1668,7 +1689,7 @@
</li>
</ol>
-<a name="N1059D"></a><a name="Using+the+C+Client"></a>
+<a name="N105AB"></a><a name="Using+the+C+Client"></a>
<h4>Using the C Client</h4>
<p>You can test your client by running a ZooKeeper server (see
instructions on the project wiki page on how to run it) and connecting
@@ -1726,7 +1747,7 @@
</div>
-<a name="N105E3"></a><a name="ch_guideToZkOperations"></a>
+<a name="N105F1"></a><a name="ch_guideToZkOperations"></a>
<h2 class="h3">Building Blocks: A Guide to ZooKeeper Operations</h2>
<div class="section">
<p>This section surveys all the operations a developer can perform
@@ -1744,28 +1765,28 @@
</li>
</ul>
-<a name="N105F7"></a><a name="sc_errorsZk"></a>
+<a name="N10605"></a><a name="sc_errorsZk"></a>
<h3 class="h4">Handling Errors</h3>
<p>Both the Java and C client bindings may report errors. The Java client
binding does so by throwing KeeperException, calling code() on the exception
will return the specific error code. The C client binding returns an error code
as defined in the enum ZOO_ERRORS. API callbacks indicate result code for both
language bindings. See the API documentation (javadoc for Java, doxygen for C)
for full details on the possible errors and their meaning.</p>
-<a name="N10601"></a><a name="sc_connectingToZk"></a>
+<a name="N1060F"></a><a name="sc_connectingToZk"></a>
<h3 class="h4">Connecting to ZooKeeper</h3>
<p></p>
-<a name="N1060A"></a><a name="sc_readOps"></a>
+<a name="N10618"></a><a name="sc_readOps"></a>
<h3 class="h4">Read Operations</h3>
<p></p>
-<a name="N10613"></a><a name="sc_writeOps"></a>
+<a name="N10621"></a><a name="sc_writeOps"></a>
<h3 class="h4">Write Operations</h3>
<p></p>
-<a name="N1061C"></a><a name="sc_handlingWatches"></a>
+<a name="N1062A"></a><a name="sc_handlingWatches"></a>
<h3 class="h4">Handling Watches</h3>
<p></p>
-<a name="N10625"></a><a name="sc_miscOps"></a>
+<a name="N10633"></a><a name="sc_miscOps"></a>
<h3 class="h4">Miscelleaneous ZooKeeper Operations</h3>
<p></p>
</div>
-<a name="N1062F"></a><a name="ch_programStructureWithExample"></a>
+<a name="N1063D"></a><a name="ch_programStructureWithExample"></a>
<h2 class="h3">Program Structure, with Simple Example</h2>
<div class="section">
<p>
@@ -1774,7 +1795,7 @@
</div>
-<a name="N1063A"></a><a name="ch_gotchas"></a>
+<a name="N10648"></a><a name="ch_gotchas"></a>
<h2 class="h3">Gotchas: Common Problems and Troubleshooting</h2>
<div class="section">
<p>So now you know ZooKeeper. It's fast, simple, your application
Modified: hadoop/zookeeper/trunk/docs/zookeeperProgrammers.pdf
URL:
http://svn.apache.org/viewvc/hadoop/zookeeper/trunk/docs/zookeeperProgrammers.pdf?rev=739082&r1=739081&r2=739082&view=diff
==============================================================================
Binary files - no diff available.
Modified:
hadoop/zookeeper/trunk/src/docs/src/documentation/content/xdocs/zookeeperProgrammers.xml
URL:
http://svn.apache.org/viewvc/hadoop/zookeeper/trunk/src/docs/src/documentation/content/xdocs/zookeeperProgrammers.xml?rev=739082&r1=739081&r2=739082&view=diff
==============================================================================
---
hadoop/zookeeper/trunk/src/docs/src/documentation/content/xdocs/zookeeperProgrammers.xml
(original)
+++
hadoop/zookeeper/trunk/src/docs/src/documentation/content/xdocs/zookeeperProgrammers.xml
Thu Jan 29 23:29:42 2009
@@ -406,6 +406,23 @@
still active. The timing of the PING is conservative enough to
ensure reasonable time to detect a dead connection and reconnect
to a new server.</para>
+
+ <para>
+ Once a connection to the server is successfully established
+ (connected) there are basically two cases where the client lib generates
+ connectionloss (the result code in c binding, exception in Java -- see
+ the API documentation for binding specific details) when either a
synchronous or
+ asynchronous operation is performed and one of the following holds:
+ </para>
+
+ <orderedlist>
+ <listitem><para>The application calls an operation on a session that is
no
+ longer alive/valid</para></listitem>
+ <listitem><para>The ZooKeeper client disconnects from a server when there
+ are pending operations to that server, i.e., there is a pending
asynchronous call.
+ </para></listitem>
+ </orderedlist>
+
</section>
<section id="ch_zkWatches">
