Table of Contents
This document briefly describes OpenLaszlo request types. It assumes that you are generally familiar with HTTP, URLs, and the OpenLaszlo architecture described in Chapter 1, OpenLaszlo Architecture.
In general, an URL that is used to request a proxied OpenLaszlo application is of the form:
http://myhost[:myport]/mywebapp/myapp.lzx?lzt=type
Everything before the ? character can typically
be configured via settings in your Servlet Container and/or
Web Server. The value of the lzt query parameter
is interpreted by the OpenLaszlo Server as a request type.
Here are the standard request types:
These request types return an HTML page that displays the
application. The mime-type of the response is
text/html.
lzt=html
This request causes the OpenLaszlo Server to respond with an HTML wrapper page
for the Laszlo application. The HTML page presents the
application. The title and background color of the application
are set to the title and background color of the application
(the values of its canvas title and
bgcolor attributes, if present).
The page that this SWF returns uses JavaScript to include the OpenLaszlo application.
lzt=html-object
Same as lzt=html, except this page embeds the
<object> and <embed> tags
directly in the HTML page. This is the traditional technique
for including applications that is used on most web sites, but
it is incompatible with the announced changes to Internet
Explorer.
lzt=windowShow the application in a popup window sized to the canvas.
These request types are used to embed an application in an HTML
page. Different requests are available depending on the request
is included on the server (object-tag) or the client
(everything else); whether the embedding technique is compatible
with the announced changes to Internet Explorer
(embed and js) or uses traditional
embedding techniques (object-tag), and whether it
creates <object> and <embed>
tags (embed, js, and
object-tag) or simply returns the swf file that
contains the application (swf).
lzt=embed
Returns a JavaScript include file that is suitable for the
target of an HTML <script> tag. The file
embeds the application into the HTML page at the site of the
<script> tag. This is appropriate for
including an application in a way that is compatible with the
announced changes to Internet Explorer.
Usage:
<script type="text/javascript" language="JavaScript"
src="http://127.0.0.1:8080/lps-4.0.3/examples/hello.lzx?lzt=embed">
</script>lzt=js
Same as lzt=embed, except the included file
depends on the functions defined in the embed.js file.
Usage:
<html>
<head>
…
<script type="text/javascript" language="JavaScript"
src="http://127.0.0.1:8080/lps-4.0.3/lps/includes/embed.js"/ >
</head>
<body>
…
<script type="text/javascript" language="JavaScript"
src="http://127.0.0.1:8080/lps-4.0.3/examples/hello.lzx?lzt=js">
</script>
…
</body>
</html>
lzt=object-tag
Returns the HTML <object> and
<embed> tags that embed the application into
an HTML page. This is useful for server-side includes, when
compatability with the announced changes to Internet Explorer is
not necessary.
lzt=swf
Returns the SWF file that represents the application, without
any HTML. This is used to embed an OpenLaszlo application in an HTML
page. (Most of the other request types generate code that
includes a URL with this request type.) The mime-type returned
by this request is application/x-shockwave-flash.
lzt=app_consoleThis request causes the OpenLaszlo Server to respond with an HTML wrapper page for the OpenLaszlo application. The HTML page presents the application. It also displays compilation warnings for the application, and links to development environment commands and developer resources. These commands are described here.
This is the default request. If no lzt query
string variable is present, the value is assumed to be
html.
The mime-type returned by this request is
text/html.
lzt=sourceShow the source in a <textarea> HTML element. The
mime-type returned by this request is text/html.
lzt=xmlShow the source as plain XML (for XML-aware browsers). The
mime-type returned by this request is text/xml.
These request types are used in the implementation and testing of the OpenLaszlo Server. Their behavior and existence should not be relied on, and they may change in future releases.
lzt=canvas-xml
lzt=deployment
lzt=inline-examples
lzt=v1
lzt=serverinfo
lzt=serverinfo returns a list of server attributes, some of which can also be fetched by an expression like Debug.write(canvas.version).
The debug=true query parameter can be used to include
the debugger in an application.
The debuglog=true query parameter can be used to
log debug messages to the server log.
The ?lzrecompile=true query parameter can be used to force the
OpenLaszlo Server to recompile an application (.lzx only, not .lzo) even when the compilation manager's
dependency option is set to never. (See Chapter 4, Deploying OpenLaszlo Applications
for details on the compilation manager's dependency option). If the administrator
password is set, you must also provide the password in pwd= query parameter
for the recompile to take effect.
The ?pwd=passwd query string can be used to pass
in the OpenLaszlo Server administrative password.
A running OpenLaszlo application can get access to any of the
query strings that was given in the URL used to access it
via the LzBrowser service's getInitArg() method. For
example if the following URL:
http://host:port/myapps/wooker.lzx?wookie=Chewie
were used to access the following app:
Example 3.1. Accessing query strings
<canvas debug="true">
<script>
var wookieName = LzBrowser.getInitArg('wookie');
Debug.write("The Wookie's Name: " + wookieName);
</script>
</canvas>
the debugger would display
The Wookie's Name: Chewie
Note that query strings that conflict with the OpenLaszlo Runime Library's global namespace will be lost (for example, "canvas" or "bgcolor").
A password may be required for Administrative Requests. See Chapter 4, Deploying OpenLaszlo Applications for more details.
lzt=log
Show the current log file as text/html.
lzt=clearlogClears the current log file.
lzt=logconfig
Show OpenLaszlo Server log4j configuration as text/xml.
lzt=clearcache
Clear OpenLaszlo Server media, data, and compilation caches.
Return a text/html status message.
lzt=serverinfo
Show OpenLaszlo Server configuration information as text/xml.
lzt=cacheinfo
Show OpenLaszlo Server media and data cache information as text/xml.
lzt=errorcount
Show the number of OpenLaszlo Server errors as text/xml.
lzt=errorcount&clear=1Clear OpenLaszlo Server error count.
lzt=statMonitor server statistics.
lzt=gcRun the garbage collector.
The OpenLaszlo Server also supports using dynamic, server-side back-end
processors (e.g., PHP, JSP) to generate LZX application source
code before the OpenLaszlo Server compiles and serves it. For URLs that end
in .lzx for which the OpenLaszlo Server can not find a matching
source file on disk, the Server removes the
.lzx suffix and uses HTTP GET to retrieve the content of
the modified URL. The returned content
should be a valid LZX file. The OpenLaszlo Server
compiles and serves an application based on the dynamically
generated source code. For example see the
hello.jsp file in the examples directory. This
example generates a Laszlo application that contains
information about the current time and session. You can see
the generated LZX source at:
http://127.0.0.1:8080/lps-4.0.3/examples/hello.jsp.lzx?lzt=source
and the generated application at:
http://127.0.0.1:8080/lps-4.0.3/examples/hello.jsp.lzx
The use of dynamically generated LZX circumvents the OpenLaszlo Server compilation cache, and compiles an application for each request. This is not recommended for use in deployment. Dynamic behavior is best handled by a static application that requests data and resources from the server during its initialization.
Copyright © 2002-2007 Laszlo Systems, Inc. All Rights Reserved. Unauthorized use, duplication or distribution is strictly prohibited. This is the proprietary information of Laszlo Systems, Inc. Use is subject to license terms.