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Publisher
1 Foreword............................................................................................................................................... 3
2 Protocol................................................................................................................................................. 3
2.1 Publishing....................................................................................................................................... 4
2.2 Unpublishing................................................................................................................................. 4
2.3 Subscribe.......................................................................................................................................... 4
2.4 Unsubscribe.................................................................................................................................... 5
3 PublisherServer................................................................................................................................ 5
3.1 Configuration............................................................................................................................... 5
3.1.1 Repository.................................................................................................................................... 6
3.1.2 PageBoxURLs.............................................................................................................................. 6
3.1.3 RepositoryURL............................................................................................................................. 7
3.1.4 Maxlength..................................................................................................................................... 7
3.1.5 ToTrace......................................................................................................................................... 7
3.1.6 LogFile.......................................................................................................................................... 7
3.2 Packaging........................................................................................................................................ 7
3.2.1 Sources.......................................................................................................................................... 7
3.2.2 Classes.......................................................................................................................................... 7
3.3 Troubleshooting........................................................................................................................ 7
3.4 Note on implementation......................................................................................................... 8
3.5 Subscription/publication display..................................................................................... 9
3.6 Archive display.......................................................................................................................... 11
4 PublisherClient.............................................................................................................................. 12
4.1 Use...................................................................................................................................................... 12
4.2 Packaging...................................................................................................................................... 13
4.2.1 Sources....................................................................................................................................... 13
4.2.2 Classes........................................................................................................................................ 13
4.3 Note on implementation....................................................................................................... 13
Four actors are involved in the PageBox architecture:
q
End user accessing presentation using browsers
q
Content providers
that write web applications and business logic. They can also host central
application and databases
q
ISP/ASP or companies hosting
the presentation. These hosts subscribe
to receive available presentations.
q
Some of these ISP/ASP also act as editors. They allow content providers to publish their presentations.
Figure 1: PageBox actors
The Content provider publishes
the presentation to the Editor. The Editor deploys
the archive to Presentation hosts. The End User accesses the Presentation that calls
the business logic using for instance EJB or JMS.
In this document, we describe the Publication tool. It
involves two parts:
q
A PublisherServer web archive
q
A PublisherClient Java application the content provider can
download from the Editor site.
The communication between the PublisherClient and the
PublisherServer uses HTTP.
It supports publishing and unpublishing, subscribe and
unsubscribe.
Note that this protocol is designed to be used between
PublisherClient and PublisherServer or from batch tools and not from a browser.
Publishing involves two steps:
1.
A sort of conditional GET to check if the archive is already
published in format http://myEditorURL?todo=check&arch=myArchive&lm=time&size=archive_size
where myArchive includes the extension .war or .jar and time is the time when the archive was modified in milliseconds since the epoch and archive_size is the size of the archive in bytes.
2.
A POST including:
a)
The archive name
b)
The time when the archive was modified in milliseconds since
the epoch
c)
The length of the archive
d)
The archive itself
e)
A variable area ended by a byte set at –1 that can contain a
certificate and a policy
f)
A certificate area contains a byte set at 33, the length of
the certificate and the certificate itself in a format that can be imported in
a keystore
g)
A policy area contains a byte set a 22, the number of
permissions and the permissions themselves
Figure
2: POST format
Unpublishing involves a single GET request in format http://myEditorURL?todo=delete&arch=myArchive,
where myArchive includes the extension .war or .jar.
Subscribe involves a single GET
request in format
http://myeditorurl/?todo=subscribe&deployURL=myJSPservlet,
where myJSPservlet is a newly subscribed JSPservlet that must receive deployed
archives.
Unsubscribe involves a single GET
request in format
http://myeditorurl/?todo=unsubscribe&deployURL=myJSPservlet, where myJSPservlet is a subscribed JSPservlet that must be removed.
<servlet>
<servlet-name>publish</servlet-name>
<servlet-class>PublisherServer.PublisherServlet</servlet-class>
<init-param>
<param-name>Repository</param-name>
<param-value>D:/Inetpub/wwwroot/Tomcat</param-value>
<description>Archive
repository</description>
</init-param>
<init-param>
<param-name>Maxlength</param-name>
<param-value>155648</param-value>
<description>Max archive
size</description>
</init-param>
<init-param>
<param-name>toTrace</param-name>
<param-value>TRUE</param-value>
<description>Trace
mode TRUE: trace</description>
</init-param>
<init-param>
<param-name>Logfile</param-name>
<param-value>C:/TEMP/publish.log</param-value>
<description>Path of log
file</description>
</init-param>
<init-param>
<param-name>PageBoxURLs</param-name>
<param-value>C:/TEMP/PageBoxURLs.ser</param-value>
<description>Serialized state of
publications and subscriptions</description>
</init-param>
<init-param>
<param-name>repositoryURL</param-name>
<param-value>localhost/Tomcat</param-value>
<description>URL where to
retrieve archives</description>
</init-param>
</servlet>
<servlet>
<servlet-name>publishLog</servlet-name>
<servlet-class>PublisherServer.PublisherLog</servlet-class>
</servlet>
<servlet>
<servlet-name>PublisherArchive</servlet-name>
<servlet-class>PublisherServer.PublisherArchive</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>publish</servlet-name>
<url-pattern>/publish</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>publishLog</servlet-name>
<url-pattern>/publishlog</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>PublisherArchive</servlet-name>
<url-pattern>/archiveList</url-pattern>
</servlet-mapping>
PublisherServer must know:
a)
where to write the archive: Repository
b)
where to deploy the archive: PageBoxURLs
c)
how JSPservletPkg can access the archive: RepositoryURL
RepositoryURL is
the URL to use to access Repository files.
Both Repository
and RepositoryURL are managed by the
Editor.
Repository is the path of the directory where PublishServer
writes archives.
The Editor must create it before starting PublisherServer.
Default: none.
This parameter is mandatory.
PageBoxURLs is the serialized state of archive publications
and subscriptions.
It is a HashMap whose keys are JSPservlet URLs and values
are of a PageBoxEntry class.
Implementation details:
A JSPservlet URL is prefixed by http:// and postfixed by
/ServletUpdate.
PageBoxEntry is defined:
class
PageBoxEntry {
boolean toRemove = false;
HashMap hm;
PageBoxEntry() {
hm = new HashMap();
}
PageBoxEntry(HashMap map) {
hm = map;
}
}
It contains two fields:
q
hm, a HashMap whose keys are archive names and values Byte
fields
q
toRemove. This field is used when an entity unsubscribes a
JSPservlet. PublisherServlet tries to undeploy the archives it manages on that
JSPservlet before removing the JSPservlet itself from PageBoxURLs. If that
JSPservlet is not running, it cannot. In this case, it sets the toRemove flag.
Then periodically it tries again to undeploy archives and remove JSPservlet. If
a new archive is published, it doesn’t deploy it to the “toRemove” JSPservlet.
The Byte field can take three values:
q
1: the archive is deployed on the JSPservlet
q
0: the archive deployment is pending – for instance because
the JSPservlet is not running
q
-1: the archive undeployment is pending - for instance because
the JSPservlet is not running
Default: none.
This parameter is mandatory.
URL where JSPservletPkg can retrieve the archive.
Default: none.
Mandatory.
Max archive length. If the archive is bigger,
PublisherServer rejects the upload request.
Default: 8192.
If set to true or TRUE, PublisherServer logs intensively.
Path of the file where PublisherServer logs.
Package PublisherServer.
PublisherServlet.java: Servlet implementing PublisherServer.
PublisherLog.java: tool to display PublisherLog.
PublisherArchive.java: tool to display published archives.
PublisherArchive.class
PublisherLog.class
PublisherServlet$Log.class
PublisherServlet$PageBoxEntry.class
PublisherServlet$PageBoxURLHandler.class
PublisherServlet$Scanner.class
PublisherServlet.class
You can use PublisherLog to remotely display the
PublisherServer log.
Figure 3: Log display
PublisherServer tries to set the date of its local archive
with the value sent by the Content provider. To do so, it uses
File.setLastModified(). This call is only supported on some platforms. If it
fails, it creates a file archive-ext.ts,
where ext is the archive extension jar or war. This file contains:
1.
A cookie, PageBox
2.
The time it received from PublisherClient
To compare the date of the archive sent by the content
provider with the date of the archive stored by the Editor, PublisherServer:
1.
Extracts the last modified time of the local archive from
archive-ext.ts if it exists
2.
Otherwise gets the last modified time using
File.getLastModified
All subscribed JSPservlet are defined with the same archives
but possibly in different states as described in PageBoxURLs section.
If a JSPservlet is subscribed, it receives the same archives
as already subscribed JSPservlet and not only the archives published after its
subscription.
PublisherServer MUST be mapped on publish.
The reason is PublisherArchive and PublisherLog need to
access to PublisherServer initialization parameters. If PublisherServer has not
been called, PublisherArchive and PublisherLog use
getServletContext().getRequestDispatcher("/publish?todo=init") to get these parameters.
If you call publish without parameter, you are displayed:
Figure 4: Subscription/publication display
You can subscribe a deployment URL.
Figure
5: subscription
display
You are displayed the screen above.
Note that if you prefixed your deployment URL by http://,
PublisherServer automatically removes it. You can now unsubscribe the deployed
PageBox.
The difference between unsubscribe and force is:
q
Unsubscribe allows unsubscribing a valid PageBox that no
longer subscribe to that particular repository. In case of unsubscribe, the
PageBox is contacted to remove the archives
q
Force removes the PageBox from the repository without
contacting it. Use it if the PageBox no longer exist or if you misspelled its
URL.
Consider the following case:
Figure 6: publications
We have two subscribers, localhost:8080/jdj and
potter/nimbus2000 and an archive, myarchive.jar is published.
Potter/nimbus2000 doesn’t exist, so myarchive is marked as
publishing on potter/nimbus2000.
As PublisherServer cannot make a difference between a
temporary unavailable PageBox and a PageBox that doesn’t exist, it periodically
tries to deploy the archive.
If we try to unsubscribe potter/nimbus2000, we get this:
Figure 7: unsubscribing
In this case, use force.
Note:
This display shows information stored in PageBoxURLs’s
PageBoxEntries.
PublisherArchive allows you to display archives deployed on
a repository.
Figure
8: Archive list
You get the following information:
q
Archive name
q
The last modified time of the archive on the publisher
machine. If the publisher tries to publish again an archive with the same
timestamp, PublisherClient will return “already published”
q
Archive permissions if provided
q
Issuer ID retrieved from the archive certificate if it
exists
Note:
This display shows information retrieved from the repository
directory.
If permission is set to yes, you can click on it to display
the permission list:
Figure 9: Permission list
PublisherClient is a Java application. Your CLASSPATH and
PATH being properly set, you invoke it with:
java PublisherClient.PublisherClient.
Then the following window is displayed:
Figure 10: PublisherClient main window
You must set the URL field to the URL of
PublisherServer.PublisherServlet on Editor side.
The second field should contain the name of the archive. Its
use is mandatory only for unpublishing. If you don’t set the field at
publication, it will be automatically set to the last part of the archive file
path. If your archive is stored in mydir/myarchive.jar, then your archive will
be published as myarchive.jar.
If you don’t set the extension, PublisherClient assumes the
extension is .jar.
There is a status line displaying the status of the last
request or “No archive selected” at startup.
You can either unpublish with “Delete archive” button or
publish with “Select archive” button. In the latter case, the following
FileChooser window is displayed:
Figure
11: Archive
selection
Once you have selected an archive, click on Publish button.
Package PublisherClient.
PublisherClient.java: Java application.
PublisherFilter.java: a filter in charge to display only jar
and war files.
PublisherClient$1.class
PublisherClient$DeleteArchive.class
PublisherClient$SelectArchive.class
PublisherClient.class
PublisherFilter.class
When you select an archive,
PublisherClient sends to PublisherServer:
1.
The archive itself
2.
Its certificate if it finds it. It has to be stored in the
same directory as the archive and to be named archive_without_extension.cer.
3.
Its policy or permission list defined according to Java 2
security. It has to be stored in the same directory as the archive and to be
named archive_without_extension.policy.
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