Pluggable resource loaders

[jakartaee]

Pluggable resource loaders

[glassfishrobot]

• Issue Imported From: https://github.com/javaee/servlet-spec/issues/2
• Original Issue Raised By:@glassfishrobot
• Original Issue Assigned To: @glassfishrobot

[glassfishrobot]

@glassfishrobot Commented
Reported by eirbjor

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Discussion on [email protected] :

http://java.net/projects/servlet-spec/lists/users/archive/2011-06/thread/1

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
I now have a working implementation of this based on Glassfish trunk.

I'll upload a patch, but I need to review the code and do some more testing first.

For now, here's a summary of changes/additions made:

---

M deployment/schemas/src/main/resources/glassfish/lib/schemas/javaee_6.xsd
M deployment/schemas/src/main/resources/glassfish/lib/schemas/web-common_3_0.xsd

Added support for new XML syntax com.example..

(I know these will need to be moved to the 3.1 / jeee7 versions of these files, but I decided not to do that now after a few failed attempts.

---

A + deployment/dol/src/main/java/com/sun/enterprise/deployment/node/web/ResourceLoaderNode.java
M deployment/dol/src/main/java/com/sun/enterprise/deployment/node/web/WebCommonNode.java
M deployment/dol/src/main/java/com/sun/enterprise/deployment/node/DescriptorFactory.java
A + deployment/dol/src/main/java/com/sun/enterprise/deployment/AppResourceLoaderDescriptorImpl.java
A + deployment/dol/src/main/java/com/sun/enterprise/deployment/web/AppResourceLoaderDescriptor.java
M deployment/dol/src/main/java/com/sun/enterprise/deployment/WebBundleDescriptor.java
M deployment/dol/src/main/java/com/sun/enterprise/deployment/xml/WebTagNames.java

Changes related to parsing the new and nodes and representing them as an AppResourceLoaderDescriptor. I pretty much stole the code from since they're structurally the same.

---

M web/javax.servlet/src/main/java/javax/servlet/ServletContext.java
A web/javax.servlet/src/main/java/javax/servlet/ResourceLoader.java

Added the ResourceLoader interface and ServletContext.addResourceLoader.

---

M web/web-core/src/main/java/org/apache/catalina/core/StandardContext.java
M web/web-core/src/main/java/org/apache/catalina/core/ApplicationContext.java
M web/web-core/src/main/java/org/apache/catalina/core/ApplicationContextFacade.java
M web/web-core/src/main/java/org/apache/catalina/servlets/DefaultServlet.java
M web/web-core/src/main/java/org/apache/catalina/Context.java
M web/web-core/src/main/resources/org/apache/catalina/core/LocalStrings.properties

• Added support for adding resource loaders, programmatically or from a class name given via XML
• Consult resource loaders when looking up resources in ServletContext's getResource*, getRealPath methods.
• Consult resource loaders when serving resources in DefaultServlet.serveResource

---

M web/web-glue/src/main/java/com/sun/enterprise/web/TomcatDeploymentConfig.java

Register the context's resource loaders by using the information available in AppResourceLoaderDescriptor

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
When adding support for resource loaders to DefaultServlet, I found the serveResource method to be hard to work with.

I've filed an issue in the Glassfish Jira for this, with some suggestions for improvements:

http://java.net/jira/browse/GLASSFISH-16871

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Patch includes API changes to the Servlet spec and a working Glassfish implementation of the changes

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Demo web application project. The webapp tests that the container implements resourceloader according to the specification.

The project also includes a demo of hot deployment of JSPs from OSGi bundles.

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Including post to user list for reference:

Thinking about it, my resource loader proposal for Servlet 3.1 might
have a multi-tenancy story as well as a dynamic deployment story.

I initially focused on a single tenant being able to dynamically
(hot)deploy resources. However, being able to define custom resource
loaders will also enable resource sharing across multiple tenants
without having to use container specific hacks or custom builds of
webapps.

I've uploaded a patch to the Jira issue which adds the ResourceLoader
interface and the ServletContext.addResourceLoader method. The patch
also includes a working implementation of resource loader support in
Glassfish trunk.

Finally, I've also uploaded a proof-of-concept web application. This
application tests the container's implementation of the ResourceLoader
API. And just for fun, I threw in a ResourceLoader backed by OSGi
bundles using Apache Felix.

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Updated poc with improved tests and getResourcePaths() implementation for OSGi

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Patch implementing ResourceLoader support for Jetty 8

[glassfishrobot]

@glassfishrobot Commented
eirbjor said:
Updates to Jetty's 3.0 Servlet Spec module adding ResourceLoader

[glassfishrobot]

@glassfishrobot Commented
File: resourceloader-poc-2011-12-15.zip
Attached By: eirbjor

[glassfishrobot]

@glassfishrobot Commented
File: SERVLET_SPEC_2-2011-12-11.patch
Attached By: eirbjor

[glassfishrobot]

@glassfishrobot Commented
File: SERVLET_SPEC_2_JETTY_8_2011-12-15.patch
Attached By: eirbjor

[glassfishrobot]

@glassfishrobot Commented
File: SERVLET_SPEC_2_JETTY_servlet-spec_2011-12-15.patch
Attached By: eirbjor

[glassfishrobot]

@glassfishrobot Commented
This issue was imported from java.net JIRA SERVLET_SPEC-2

@gregw I would favor for the deployment model to stick to WAR file or WAR file exploded in a directory to be the 2 ways that have to be supported. Any other really should be left up to the vendor.