An introduction to Open Services for Lifecycle Collaboration (OSLC): - The OSLC community - Linked Data and RDF - OSLC specifications

1. An Introduction to OSLC and Linked Data
OSLC: Lifecycle integration inspired by the web

2. Objectives and Pre-requisites
Objectives:
 You will gain an understanding of the OSLC community,
linked data, and the OSLC specifications
– OSLC = Open Services for Lifecycle Collaboration
Pre-requisites:
 none
Recommended reading:
1. http://www.linkeddatatools.com/introducing-rdf
2. http://3roundstones.com/linked-data-101/linked-data-tu
2

3. What’s next
The OSLC community
Linked data and RDF
An example
The OSLC specifications
3

4. The Integration Problem
Point-to-point
Monocultures Maintenance, management,
Integrations
lock you in and change costs go up over time
don’t scale
Ongoing and unexpected
costs drain resources
End-user productivity suffers:
End-user productivity suffers:
Either stuck with the wrong tool,
Either stuck with the wrong tool,
stuck doing manual integration;
stuck doing manual integration;
often stuck doing both
often stuck doing both
Creating new Past choices
integrations is restrict present Integrations consume more of the IT budget:
Integrations consume more of the IT budget:
unpredictable action and integration failures are the top 2 causes
integration failures are the top 2 causes
future vision of software project delays*
of software project delays*
More limited ability to respond to change
More limited ability to respond to change
Constrained by exhausted IT budget and lower productivity
Constrained by exhausted IT budget and lower productivity * Commissioned study conducted by
Forrester Consulting on behalf of IBM.
4

5. OSLC and Open Community: open collaboration, better integration
Identify Iterate on
Scenarios working
drafts
Call it a Gain technical
specification consensus,
http://open-services.net
5

6. The Basics: What is OSLC, and why should I care?
OSLC is an open community building practical
specifications for integrating software
OSLC is beneficial to many stakeholders
6

7. OSLC’s Simple Solution
Users can work seamlessly across their tools
Architecture of the Web Standard Interfaces
Automation
Linked Data “Just Enough” integration
Increased reuse Increased traceability
Monitoring
Decreased maintenance costs Better visibility
OSLC is an open and scalable approach to lifecycle integration.
It simplifies key integration scenarios across heterogeneous tools
7

8. OSLC’s Big Picture
Tests, Libraries, Samples, Examples,
The Resource Reference Implementations
for OSLC
Implementers
FFuu
ut tu
rr
OSLL eeHoome
OS C H me o
CSpp
S eec off
c De
Dev
v
LINKED DATA PLATFORM WORKING GROUP
Open Services for Lifecycle Collaboration
Lifecycle integration inspired by the web
Scenario-driven &
Solution-oriented
Leading choice for
strategic integration
technology Generally applicable: specs available for many
domains covering ALM, DevOps, ISM, and PLM
Inspired by the web Free to use and share Changing the industry
OSLC: Proven Open Innovative
8

9. Eclipse Lyo
Eclipse project created with the goal of providing tools to
enable adoption of OSLC specifications.
Content includes
 Code libraries (Java, Perl, others under development)
– Give developers tools to ease OSLC implementations
 Reference implementations of specifications
– Provide a starting point for new integrations
 Test suites and test reporting. Covers OSLC Core, CM, QM, RM
and Asset today.
– Accelerate and assess development
 Samples, tutorials and documentation
– Working samples of OSLC integrations with Bugzilla, Excel,
Jazz tools and more.
http://eclipse.org/lyo
9

10. What’s next
The OSLC community
Linked data and RDF
An example
The OSLC specifications
10

11. OSLC turns data into...
Requirements Validation Tests Design Implementation
T1
R1 D1 I1
R2 D2 I2
T2
Tool A Tool B Tool C Tool D
11

12. ...connected information...
Requirements Validation Tests Design Implementation
T1
validates validates
R1 D1 I1
satisfy implements
satisfy implements
R2 D2 I2
validates
validates
T2
Tool A Tool B Tool C Tool D
Which requirements for
Which requirements for
Does every requirement
Does every requirement the UI are related to test
the UI are related to test
have aatest to validate it?
have test to validate it? cases that failed on their
cases that failed on their
last run?
last run?
12

13. ...that can facilitate applied knowledge
Requirements Validation Tests Design Implementation
User Interface
T1
validates validates
R1 D1 I1
satisfy implements
Release
satisfy implements
R2 D2 I2
validates
validates
T2 Processing Engine
Tool A Tool B Tool C Tool D
Why is the number of
Why is the number of How much faster is work
How much faster is work
failed test cases for the UI
failed test cases for the UI progressing on the UI
progressing on the UI
increasing in each
increasing in each versus the Processing
versus the Processing
iteration?
iteration? Engine?
Engine?
13

14. OSLC links lifecycle data
14

15. Linked Data and RDF
Tim Berners-Lee’s four principles for linking data:
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up those names
3. When someone looks up a URI, provide useful information
using the standards (RDF, SPARQL)
4. Include links to other URIs so that they can discover more
things
“Instead of defining a new data model, OSLC’s resource and
property-value approach is based on industry standard Resource
Description Framework (RDF) data model.”
Adapted from: http://open-services.net/bin/view/Main/ OslcCoreSpecification
15

16. RDF Concepts
OSLC applies some RDF key concepts:
1. Graph data model
2. URI-based vocabulary
3. Format - Serialization syntaxes (RDF/XML, Turtle,
JSON)
4. Datatypes
5. Literals
6. Expression of simple facts
7. Entailment
We’ll briefly look at some of them.
16

17. 1. OSLC uses an RDF graph data model
Predicate
Subject Object
owns
Amanda Car
validates
Test Case 1 Requirement 1
The predicate provides the property or relationship
between the subject and object.
Adapted from:
http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-data-model
17

18. 2. OSLC uses a URI-based vocabulary
When there is a need to identify anything in OSLC,
use a URI (there are a few exceptions).
Using URIs allows everything to be linked together. It
also allows common agreed-upon meaning for
relationships and for resource types
<http://...Test Case 1> <http://...validates> <http://...Requirement 1>
OSLC Core URI Naming Guidance:
http://open-services.net/wiki/core/OSLC-Core-URI-Naming-Guidance/
18

19. 3. OSLC allows different RDF formats
The RDF model provides for describing RDF triples.
There are various supported formats. Some are
specialized for RDF (Turtle) and others are derived
from existing formats (XML, JSON). These formats can
be exchanged between different applications (tools).
OSLC allows different types of format:
 RDF/XML
 Turtle
 JSON
OSLC Core Specification:
http://open-services.net/bin/view/Main/OslcCoreSpecification
19

20. Examples of different OSLC notations
Predicate
Subject Object
<http://...Test Case 1> <http://...validates> <http://...Requirement 1>
<http://example.com/TestCases/1> a oslc_qm:TestCase ;
Turtle
oslc_qm:validatesRequirement <http://example.com/Requirements/1>
{
"rdf:about": "http://example.com/TestCases/1",
"rdf:type": [ {
"rdf:resource": "http://open-services.net/ns/qm#TestPlan"
} ],
JSON
"oslc_qm:validatesRequirement": {
"rdf:resource": "http://example.com/Requirements/1"
}
}
<oslc_qm:TestCase rdf:about="http://example.com/TestCases/1">
<oslc_qm:validatesRequirement rdf:resource="http://example.com/Requirements/1"/>
</oslc_qm:TestCase> RDF/XML
20

21. What’s next
The OSLC community
Linked data and RDF
An example
The OSLC specifications
This example is adapted from http://3roundstones.com/linked-
data-101/linked-data-tutorial/ [David Wood, 3RoundStonesInc.
November2011]
21

22. Here’s a fictional project
Existing product: Lunar
Rover 3.0
New Release: Lunar
Rover 3.1
Main goal is to improve
remote steering
Release to orbit date:
September 20, 2014
22

23. Let’s look at the requirements domain
Requirement 28465 Improve Remote
Steering
owner release Lunar Rover 3.1
Bob
priority
High
owned by
Iris
created on
November 24,
release to
2011
orbit date
September 20,
state 2014
Implemented
23

24. The same information as before, in tabular form
Requirement Owner Priority Created on State Release
Requirement 28464 Linda Low October 18, New Lunar Rover
Add rear FIDO mast 2012 3.1
Requirement 28465 Bob High November 24, Implemented Lunar Rover
Improve Remote 2011 3.1
Steering
Requirement 28466 Tanuj Medium September 9, Reviewed Lunar Rover
Rebuild wheels for soil 2012 3.1
excavation
Rover Release Owned by Release to orbit
date
Lunar Rover 3.0 Cheng August 16, 2011
Lunar Rover 3.1 Iris Sept 14, 2014
24

25. Let’s look at the quality domain
Test Case 35645: Test Steering
owner release Lunar Rover 3.1
Janet
priority
High
owned by
Iris
created on
December 7, release to
2011 orbit date
September 20,
state 2014
Executed
result
pass
25

26. Let’s add more relationships
validated by
Test Case 35645: Test
Steering
release
Requirement 28465
Improve Remote Steering
owner
Janet
release Lunar Rover
owner
Bob 3.1 priority
High
priority
High created on
owner December
Iris 7, 2011
created on
November 24,
2011 state
release to Executed
orbit date September
20, 2014
state
Implemented
result pass
26

27. The same information as before, in tabular form
Requirement Owner Priority Created State Release Validated by
on
Requirement Linda Low October 18, New Lunar
28464 Add rear 2012 Rover 3.1
FIDO mast
Requirement Bob High November Implemented Lunar Test Case
28465 Improve 24, 2011 Rover 3.1 35645: Test
Remote Steering Steering
Requirement Tanuj Medium September Reviewed Lunar Lunar Rover 3.1
28466 Rebuild 9, 2012 Rover 3.1
wheels for soil
excavation
Rover Owner Release to Test Case Owner Priority ...
Release orbit date
Lunar Cheng August 16, 2011 Test Case 35645 Janet High ...
Rover 3.0 Test Steering
Lunar Iris Sept 14, 2014 Lunar Rover 3.1 Iris ...
Rover 3.1
27

28. RDF triple (subject-predicate-object)
Triple
Subject = Resource Predicate = Object = Could be a
= always a URI Relationship or URI (which could refer
property = Always a to a resource) or a
URI literal value (value to
work with and show
users)
Requirement validated by Test Case
28465 Improve 35645: Test
Remote Steering Steering
priority
High
28

29. RDF triple (subject-predicate-object)
Triple
Subject = Resource Predicate = Object = Could be a
= always a URI Relationship or URI (which could refer
property = Always a to a resource) or a
URI literal value (value to
work with and show
users)
<http://...require <http://...validatedby> <http://...testcas
ment28465_ e35645_test_ste
improve_remote ering>
steering>
<http://...priority>
“High”
29

30. Let’s add more relationships
Work Item
38759
implements validated by Test Case 35645: Test
Steering
release
Requirement 28465
Improve Remote Steering
owner
Janet
owner release
Bob Lunar Rover 3.1 priority
High
priority
High owner created on
December
Iris
7, 2011
created on
November 24, state
2011 release to
orbit date Executed
September
20, 2014
state
Implemented result
pass
30

31. There is a web of URIs around a development effort
<http://.../build>
<http://.../testresult
> <http://.../change
<http://.../build>
request>
<http://.../build>
<http://.../test <http://.../workitem <http://.../testresult
<http://.../req> case> >
>
<http://.../test
case>
<http://.../bug>
<http://.../workitem
>
<http://.../build> <http://.../req> <http://.../change
request>
<http://.../workitem
<http://.../test <http://.../bug> >
<http://.../release> <http://.../req>
case>
<http://.../build>
<http://.../bug>
validate
<http://.../build>
<http://.../workitem <http://.../test
<http://.../req> > case>
<http://.../workitem <http://.../build>
<http://.../change <http://.../test >
request> case>
<http://.../change <http://.../change
<http://.../req> request> request> <http://.../testresult
>
<http://.../testresult
>
<http://.../testresult
>
<http://.../change
request>
31

32. OSLC principles
Tim Berners-Lee’s four principles applied to OSLC:
 Use URIs as names for things
– In OSLC, each artifact in the lifecycle (for example, requirements,
change requests, test cases...) is identified by a URI.
 Use HTTP URIs so that people can look up those names.
– In OSLC, each artifact in the lifecycle is an HTTP resource.
Standard HTTP methods (GET, PUT, POST, DELETE) are used to
interact with them.
 When someone looks up a URI, provide useful information using the
standards (RDF*, SPARQL)
– Each OSLC resource has an RDF representation. OSLC resources
can be queried using SPARQL.
 Include links to other URIs so that they can discover more things.
– OSLC lifecycle artifacts are linked by relationships (for example,
validatesRequirement or testedByTestCase) which are defined by
URIs.
32

33. What’s next
The OSLC community
Linked data and RDF
An example
The OSLC specifications
33

34. Anatomy of a specification
Core: Specifies the primary integration
OSLC Core Specification techniques for integrating lifecycle tools
– the standard rules and patterns for
using HTTP and RDF that all the domain
How workgroups must adopt in their
specifications
Domain: Defines integration scenarios
OSLC Change Mgt for a given lifecycle topic and specifies a
Specification
common vocabulary for the lifecycle
artifacts needed to support the
scenarios.
OSLC Requirements Example: The Core specification
Specification describes Delegated UIs and Creation
Factories and states that OSLC service
providers MAY provide them. The
Change Management specification
OSLC Domain X states that CM service providers MUST
Specification provide them.
http://open-services.net/bin/view/Main/OslcCoreSpecification
34

35. OSLC defines the following technical areas:
1. Discovery of 2. HTTP C.R.U.D. for
capabilities resources
6. UI Previews for 3. Standard resource
Resource Links representations
5. Delegated UI for 4. Querying for
Create and Select resources
35

36. First, some terminology (before we get to #1)
OSLC Service These catalogs are used in the discovery of
Provider catalog OSLC service providers. They help to simplify
the configuration of tools that will integrate
provides with providers of OSLC-defined services.
example: IBM Rational Team
Concert
OSLC Service A product or online service offering that
Provider provides an implementation of one or more
OSLC Services, which may themselves
provides an implement different OSLC Domain example: IBM Rational Team
implementation of specifications Concert project area
Set of capabilities that enable a web client to
OSLC Service create, retrieve, update and delete resources
managed by an ALM or PLM product or online
service offering and associated with one example: Change Management
OSLC Domain capability
manages
Managed by an OSLC Service, may have
properties and may link to other resources
including those provided by other OSLC
OSLC Resource example: work item (bug,
Services.
defect, enhancement request)
36

37. 1. Discovery of capabilities
Starting from the catalog you
can discover services and their
capabilities. This is a common
pattern in OSLC.
OSLC capabilities:
Delegated UI Dialog allows you to
create or find resources using a UI
provided by the OSLC tool
Creation Factory allows you to
create resources programmatically
Query Capability allows you to
query for resources
37

38. 2. HTTP C.R.U.D
OSLC allows manipulation of resources using standard
HTTP C.R.U.D
Create = POST
Request = GET
Update = PUT
Delete = DELETE
38

39. Resource Creation (Create)
Create a resource using HTTP POST, with the resource body in format
of choice
 URI for doing the POST is defined in the oslc:ServiceProvider in the
oslc:creationFactory service
Response is a 201-Created with Location HTTP header indicating
URI for resource
Request may be rejected for any number of reasons
 Insufficient permissions
 Missing required values
 Invalid data choices
 ...and … and ...
Valid resource formats for creation are defined by:
 domain specifications
 service provider may define its own resources and formats
 optionally, by resource shape associated with creation factory
39

40. Resource Retrieval (Request)
Use HTTP GET and standard HTTP content negotiation
 Client uses HTTP Accept request header to specify desired resource formats
Accept: application/json, application/xml
Use standard content(MIME) types
Partial representations can be requested via HTTP URL key=value pair as ?
oslc.properties=
 Allows for minimal retrieval of properties
 Get Defect 123 (all properties)
GET http://bugs/123
 Get Defect 123 (just title and status)
GET http://bugs/123?oslc.properties=dcterms:title,oslc_cm:status
40

41. Resource Modification (Update)
Use HTTP GET to get resource properties to be updated
 You’ll get an ETag back
Change only the property values you need to change
 Clients must preserve unknown content
Use HTTP PUT to send updated resource
 Use If-Match HTTP request header with ETag, services may reject
your request without it
 HTTP PUT will completely replace the resource representation
 We are moving towards PATCH – new HTTP verb
http://tools.ietf.org/html/rfc5789
It is possible to update only selected properties
41

42. Resource Deletion (Delete)
Use HTTP DELETE on the resource identifier
May not be allowed
Response usually:
• 200-OK
• 204-No-Content
• 400-Bad-Request
• 403-Forbidden
42

43. 3. Resource representations
OSLC services should handle any type of resource
 Not just those defined by OSLC
Resources defined by OSLC use RDF data model
 therefore are simply defined by their set of properties
OSLC services MUST produce and consume RDF/XML
representations
 Clients and services MUST NOT assume any subset of RDF/XML
Other representations are allowed such as:
 XML: OSLC defined format that allows for consistent formats and is
RDF/XML valid
 JSON: Rules for representing namespaces and QName properties
 Turtle: No constraints, use as is (may be preferred by future specs)
 Atom Syndication Format: <atom:content> SHOULD be RDF/XML
43

44. A few words on Resource Linking
Links are properties where the property values are
URIs
Turtle format for a bug resource (abbreviated)
<http://example.com/bugs/2314>
a oslc_cm:ChangeRequest ;
dcterms:relation
<http://server/app/bugs/1235> ;
Don't make assumptions about the target of links
 OSLC supports an open model
 Needed to achieve goal of “loosely coupled” integrations
 Clients need to be flexible and expect anything
Sometimes we need to provide additional data about
links: label, owners, and so on.
Special cases where links need more representation
44

45. 4. Querying for resources
Query capability has base URI
Clients form query URI and HTTP GET the results
OSLC services MAY support OSLC Query Syntax
 http://open-services.net/bin/view/Main/OSLCCoreSpecQuery
45

46. Query syntax overview
 Filter results by appending “oslc.where=” with query clause to query base URI
 Only boolean operation allowed is “and” which represents conjunction
 “or” for disjunction is not defined in the interests of keeping the syntax simple.
 Retrieve just what you want with “oslc.select=”
 Defined ordering using “oslc.orderBy=”
 Full-text search via “oslc.searchTerms=”
Comparison Operators
= test for equality
!= test for inequality
'in' operator:
< test less-than
Test for equality to any of the
values in a list. The list is a > test greater-than
comma-separated sequence <= test less-than or equal
of values, enclosed in square >= test greater-than or equal
brackets: in [“high”,”critical”]
46

47. Query syntax example
Find high severity bugs created after April fools day
http://example.com/bugs?oslc.where=
cm:severity="high" and dcterms:created>"2010-04-01"
Find bugs related to test case 31459
http://example.com/bugs?oslc.prefix=qm=
<http://qm.example.com/ns>&
oslc.where=qm:testcase=<http://example.com/tests/31459>
Find all bugs created by John Smith
http://example.com/bugs?oslc.where=
dcterms:creator{
foaf:givenName="John" and foaf:familyName="Smith"}
47

48. 5. Delegated UI renders the source app UI in the target app
A delegated UI renders the source
application UI in the target application. This
example shows the contributed/delegated 2. iframe's src
Rational Team Concert Work Item search set to delegated
dialog being rendered in an OSLC Quality UI's URL
Management application.
1. Click to
launch
delegated UI
4. Click OK.
Sends message 3. Selection
(link+label) to made
parent window
48

49. Delegated UI key points
Delegated UIs support both creation and selection of resources
Two communication protocols are supported for iframes:
 HTML5 postMessage() ← preferred method
– Supported in most modern browers
 Window object's window.name
– Supported in older browsers and Eclipse embedded web widget
 Consumer selects which protocol to use, informs provider via fragment
identifier
Tremendous value for resource creation
 Traditionally most service logic was communicated to client and new
dialog built
 Now the rules for creation and dialog change as needed
Prefilling of creation dialog done by “creating” a dialog resource
 HTTP POST of resource format to creation dialog URL, response is URL
of dialog prefilled
49

50. 6. UI Preview
Scenario supported: hover over link to get in context preview of resource
Simple resource format defined and retrieved using HTTP content
negotiation
Hover over link
50

51. OSLC specifications also include
 Common property and resource definitions covering
 Resource shapes
 Resource typical properties: title, description, identification, …
 Leveraging Dublin Core and FOAF
 Discussion/comments
 OSLC services MAY offer OAuth 1.0a
 Three legged OAuth for webapp to webapp authentication
 Two legged OAuth for client to webapp authentication
 OSLC services MAY offer HTTP BASIC Auth
 User name and password sent “in the clear” with Base64 encoding
 Should be done via HTTPS only
51

52. OSLC Specifications Cover Many Domains
Core & Common
• Core, Configuration Management, Reporting
Application Lifecycle Management (ALM)
• Change Management, Quality Management, Requirements
Management, Asset Management, Architecture
Management, Automation
(Software) Project Management
• Estimation and Reporting
Product Lifecycle Management (PLM)
• ALM-PLM Interoperability
Integrated Service Management (ISM)
• Performance Monitoring, Reconciliation
52

53. Get Connected with OSLC
 Learn more at
 http://open-services.net
 http://eclipse.org/lyo
 Get started with your OSLC “Hello World!” with
Eclipse Lyo and existing specs
 Join the community and contribute scenarios
 Jump in and create specifications that matter to
you
Open Services for Lifecycle Collaboration
Lifecycle integration inspired by the web
53

54. Resources
OSLC Web Site
 http://open-services.net
OSLC Primer
 http://open-services.net/primer
OSLC Tutorial
 http://open-services.net/tutorial
OSLC Core and Domain specifications
 http://open-services.net/specifications/
Eclipse Lyo
 http://www.eclipse.org/lyo/
Even more OSLC resources
 http://open-services.net/resources/
54

55. BACKUP
55

56. Need better integration approaches
Past integration approaches have provided limited choice and coverage.
Single repository Point-to-point integrations
“Can I really expect one vendor “How can I ever upgrade one
to provide all the functionality I tool without breaking
need? And what about my everything else?”
existing tools?”
Past integration approaches have been disruptive and slow to emerge.
Universal metadata standard Standard implementations
“How did I ever think all those “Did I really believe that every
vendors would be able to vendor would rewrite their
agree?” tools on a single framework?”
56

57. Need open collaboration on solutions
Past collaborations have fallen short because of limited and
restrictive participation.
Limited to small set of business partners Point-to-point integrations

Built after the fact with limited

No open process for others to join in
product APIs

Limits solution to particular use cases 
Solution focuses on two tools in
and technologies
hand
Solution design goals and approach Restrictive licenses and intellectual property

No consensus driven approach 
License fees

No external review 
Fear of giving up IP

No visibility into solution 
Forces alternative solutions
57

58. OSLC community
Vendors, end users, industry consortia
Wide range of
40+ organizations have had employees participate in
interests, specification development efforts
expertise, 100s of developers have used assets from Lyo
participation Collaborating on solutions for ALM, DevOps, ISM, PLM
 Implementations from IBM Rational, Oracle, IBM Tivoli
and open source
Growing list of 3rd party adapters from IBM, Kovair, Tasktop, and open
implementations source
Dozens of end users enabling homegrown tools
Change Management, Quality Management,
Requirements Management, Asset Management,
Specifications for Architecture Management, Automation
many domains Product Lifecycle Management, Configuration
Management
Performance Monitoring, Reconciliation
58

59. OSLC website at http://open-services.net
Register Learn Adopt Browse Participate
59