OSGi DevCon 2013 his talk will present the state of the specification work following up on RFP-150, Http Service Updates. This is a major update to one of the first service specification of the OSGi Alliance in three areas: Support for new Servlet API specifications published since then such as Servlet Filters, Event Listeners and error pages support for the registration of Servlets and Filters using the whiteboard pattern clarification of interactions between the Http Service and an underlying Servlet Container.

1. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
What‘s new in Http Service
Felix Meschberger, Adobe
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1Dienstag, 26. März 13

2. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Setting the Scope
2
Web
Applications
Specification
Web Applications
Support
Http Service
Specification
Web Applications
OSGi-style
2Dienstag, 26. März 13

3. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Http Service 1.2
§ More or less unmodified since OSGi R1 (May, 2000)
§ Resource Registration
§ Custom Authentication
§ Based on Servlet API 2.1 (November, 1998)
§ Error Pages (Servlet API 2.2)
§ Filters (Servlet API 2.3)
§ Application Events (Servlet API 2.3)
§ Limited Servlet Registration (path prefix only)
§ Complex registration:
§ Requires HttpService to register
§ Requires keeping state of successful registration
§ Requires Http Service to unregister
3
901 San Antonio Road
Palo Alto, CA 94303 USA
415 960-1300 fax 415 969-9131
A Division of Sun Microsystems, Inc.
Java™ Servlet API
Specification
Version 2.1a
James Duncan Davidson
with Suzanne Ahmed
November 1998
Java Software Division
OSGi Service Gateway Specification
Release 1.0
May, 2000
Copyright © The Open Services Gateway Initiative (2000). All Rights Reserved.
Implementation of certain elements of the Open Services Gateway Initiative (OSGI)
Specification may be subject to third party intellectual property rights, including without
limitation, patent rights (such a third party may or may not be a member of OSGi). OSGi is
not responsible and shall not be held responsible in any manner for identifying or failing to
identify any or all such third party intellectual property rights. This document and the
information contained herein are provided on an "AS IS" basis and OSGI DISCLAIMS
ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT
INFRINGE ANY RIGHTS AND ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
WILL OSGI BE LIABLE FOR ANY LOSS OF PROFITS, LOSS OF BUSINESS, LOSS
OF USE OF DATA, INTERRUPTION OF BUSINESS, OR FOR DIRECT, INDIRECT,
SPECIAL OR EXEMPLARY, INCIDENTIAL, PUNITIVE OR CONSEQUENTIAL
DAMAGES OF ANY KIND IN CONNECTION WITH THIS DOCUMENT OR THE
INFORMATION CONTAINED HEREIN, EVEN IF ADVISED OF THE POSSIBILITY
OF SUCH LOSS OR DAMAGE.
All Company, brand and product names may be trademarks that are the sole property of
their respective owners. All rights reserved.
OSGi Service Gateway Specification Release 1.0
http://curie.eng/OSGi/index.html (1 of 2) [4/27/2000 12:29:54 PM]
3Dienstag, 26. März 13

4. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Where will Http Service Go ?
§ Servlet API Version
§ Web Application Descriptor Elements
§ Simpler Registration
§ Clarify Relationship between HttpContext and ServletContext
§ Diagnostic API (based on RFC 185 / Data Transfer Objects)
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5. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Requirements 1: Http Service Updates
HS-1 The solution MUST define the relationship between the Http Service and Web Application specifications.
HS-2 The solution MUST update the Http Service specification to refer to the latest Servlet API specification and define to what
extend the Http Service provides support.
HS-3 The solution MUST extend the HttpService service API to support Servlet registration with patterns as defined by the
Servlet API specification (Section 12.2, Specification of Mappings, in the Servlet API 3.0 specification). This requirement
aligns servlet registration to functionality provided by the Servlet API web application descriptor (web.xml).
HS-4 The solution MUST extend the HttpService service API to support registration of Servlet API filters with patterns as
defined by the Servlet API specification (Section 12.2, Specification of Mappings, in the Servlet API 3.0 specification) or
referring to servlets by their names. This requirement aligns mapping filters to requests to functionality provided by the
Servlet API web application descriptor (web.xml).
HS-5 The solution MUST extend the HttpService service API to support registration of Servlet API listeners.
HS-6 The solution MUST add support for error page configuration.
HS-7 The solution MUST define how registered Servlets and Filters are named.
HS-8 The solution MUST clarify ServletContext implementation in the HttpService for both standalone and bridged Http
Service implementations.
HS-9 The solution MUST clarify the ServletContext scope of Servlet API listeners registered through the HttpService.
HS-10 The solution MAY specify support for scripted request processing. For example supporting JSP with Tag Libraries.
HS-11 The solution MAY define how HttpService instances can be dynamically configured.
HS-12 The solution MUST define service registration properties for the HttpService to reflect configuration of the service.
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6. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Requirements 2: Whiteboard Registration
HS-13 The solution MUST define whiteboard registration of servlet services with the HttpService.
HS-14 The solution MUST define whiteboard registration of filter services with the HttpService.
HS-15 The solution MUST define whiteboard registration of servlet listener services with the HttpService.
HS-16 The solution MUST define registration of OSGi HttpContext services used for Servlet and Filter registration.
HS-17 The solution MUST define how servlets, filters, and servlet listener services are matched with HttpService services for
registration.
HS-18 The solution MUST support registration of static resources according to the extender pattern.
HS-19 The solution MUST support registration of error pages according to the extender pattern.
HS-20 The solution MUST define a capability for the osgi.extender namespace. Bundles providing resources and/or error pages
can then require this capability.
HS-21 The solution MUST define a capability for the whiteboard pattern registration in one of the standard namespaces (or a
new namespace to be defined in the Chapter 135, Common Namespaces Specification). Bundles registering servlet, filter,
and/or servlet listener services can then require this capability.
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6Dienstag, 26. März 13

7. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Servlet API Version
§ Which Servlet API to support/require ?
§ Servlet API 3.0 for the latest and greatest ?
§ Must not alienate Embedded Systems !
§ Servlet API and the Platform
§ 2.4 requires Java 1.3
§ 2.5 requires Java 5
§ 3.0 requires Java 6
7
>= 2.4
7Dienstag, 26. März 13

8. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Web Application Descriptor Elements
8
Servlet
Filter
Error
Pages
Event
Listener
EJB
MIME
mapping
Replacements
• EJB: Use Services
• MIME mapping: Use HttpContext
8Dienstag, 26. März 13

9. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Registration - Http Service 1.2 API
9
public interface HttpService {
public void registerServlet(String alias,
Servlet servlet,
Dictionary initparams,
HttpContext context)
throws ServletException, NamespaceException;
public void unregister(String alias);
}
Single path Prefix only
Servlet or
Resource ?
Manage
State
Service
Required
Share ?
9Dienstag, 26. März 13

10. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Registration - Http Service 1.2 Example
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@Component(service = {}, property = "alias=/")
public class SampleServletOld extends HttpServlet {
private HttpService httpService;
private String servletAlias;
private boolean servletRegistered;
@Activate
private void activate(Map<String, Object> config) throws ServletException, NamespaceException {
this.servletAlias = (String) config.get("alias");
this.httpService.registerServlet(this.servletAlias, this, null, null);
this.servletRegistered = true;
}
@Deactivate
private void deactivate() {
if (this.servletRegistered) {
this.httpService.unregister(servletAlias);
}
}
@Reference(unbind = "unbindHttpService")
private void bindHttpService(final HttpService httpService) {
this.httpService = httpService;
}
private void unbindHttpService(final HttpService httpService) {
if (this.httpService == httpService) {
this.httpService = null;
}
}
}
Manage
State
Service
Required
10Dienstag, 26. März 13

11. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Registration - Whiteboard Pattern
11
@Component(
service = Servlet.class,
property = "osgi.http.whiteboard.pattern=/")
public class SampleServletWhiteboard extends HttpServlet {
}
§ No Http Service reference
§ No State Management
11Dienstag, 26. März 13

12. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Http Context and Servlet Context
12
Common Servlet Context
(e.g. from Servlet Container)
Servlet Context 1 Servlet Context n
Http Context 1 Http Context n
Context Path
Logging
Version
Attributes
Resources
HTTP Sessions
Attributes
Resources
HTTP Sessions
Authentication
MIME Types
Authentication
MIME Types
12Dienstag, 26. März 13

13. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Whiteboard Pattern Support Explained
§ Uses Servlet, Filter, HttpContext services
§ Registers with Http Service
§ Matches Servlet to HttpContext with context.name property
13
Servlet
HttpContext
Http Service
context.name
pattern
Filter
pattern
13Dienstag, 26. März 13

14. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Http Service Whiteboard Properties
14
osgi.http.whiteboard. Servlet HttpContext Filter
.pattern
.context.name
.context.shared
.errorPage
.service.target
.prefix
Registration
Pattern
n/a
Registration
Pattern
Refers to
HttpContext
Identifies
Refers to
HttpContext
n/a
Shared across
Bundles ?
n/a
Status Code
Exception Type
n/a n/a
HttpService
Selection
n/a
HttpService
Selection
Resource Prefix n/a n/a
14Dienstag, 26. März 13

15. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Alias vs. Pattern
15
Http Service Servlet API Match Type
/alias /prefix/* Prefix Match
*.ext Extension Match
„“ (empty) Context Root Match
/ Default Servlet
/exact/match Exact Match
§ osgi.http.whiteboard.pattern Service Registration Property
§ String+: String, String[], Collection<String>
15Dienstag, 26. März 13

16. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Application Events
§ Listeners are Services
§ Listener interface is Service Name
§ Supported Listeners depending on Servlet API Support
§ Whiteboard Registration
§ All Events from Http Service
§ Exception: ServletContextListener
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16Dienstag, 26. März 13

17. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Diagnostic API
§ ServletDTO[] getServlets();
§ Map<String, String> getResources();
§ FilterDTO[] getFilters();
§ Map<Object, String> getErrorLocations();
17
FilterDTO
- String name;
- String[] patterns;
- ServletContextDTO servletContext;
ServletDTO
- String name;
- String[] patterns;
- String servletInfo;
- ServletContextDTO servletContext;
ServletContextDTO
- String name;
- String contextPath;
- Map<String, Object> initParams;
- Map<String, Object> attributes;
17Dienstag, 26. März 13

18. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
What else ?
§ Resources
§ Replacement for HttpService.registerResources
§ org.osgi.service.http.Resource Servlet
§ osgi.http.whiteboard.pattern - String+ of URL patterns
§ osgi.http.whiteboard.prefix - String of name prefix
§ Http Service Registration Property
§ osgi.http.service.endpoints - String+ of endpoint URIs, e.g. http://127.0.0.1:4502
§ Capability / Namespace
§ New namespace osgi.whiteboard
§ Whiteboard Capability: osgi.http
18
Provide-Capability: osgi.whiteboard;
osgi.whiteboard="osgi.http";
uses:="javax.servlet";
version:Version="1.3"
Require-Capability: osgi.whiteboard;
filter:="(&(osgi.whiteboard=osgi.http)(version>=1.3))"
18Dienstag, 26. März 13

19. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Good News
19
© 2013 OSGi Alliance
All Rights Reserved.
OSGi Early Draft
2013.03
4 March 2013
19Dienstag, 26. März 13

20. © 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Links
§ http://wiki.osgi.org/wiki/WebExperience
§ OSGi Early Access Draft 2013-03
§ http://www.osgi.org/Download/File?url=/download/osgi-early-draft-2013-03.pdf
§ Discuss
§ mailto:osgi-dev@mail.osgi.org
§ OSGi Service Gateway Specification Releases 1.0
§ http://www.osgi.org/Download/Release1
§ OSGi Enterprise Release 5
§ http://www.osgi.org/Download/Release5
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20Dienstag, 26. März 13

21. 1 Sign In: www.eclipsecon.org
2 Select Session Evaluate
3 Vote
© 2011 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.
Give Feedback on the Session
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