Role and Use of Ontologies in the Open Semantic Framework

Frederick Giasson
Ontologies are to the Open Semantic Framework what humans were to the Mechanical Turk. The hidden human in the Mechanical Turk was orchestrating all and every chess move. However, to the observers, the automated chess machine was looking just like it: a new kind of intelligent machine. We were in 1770.

Ontologies plays exactly the same role for the Open Semantic Framework (OSF): they orchestrate all and every moves for all the pieces within OSF. They are what instructs structWSF, the Semantic Components, conStruct, and all other derivate pieces of user interfaces how to behave.

In this (lengthy) blog post, I will present the main ontologies that have an impact on different parts of OSF. We will see how different ontology classes and properties, and how the description of the records indexed in the system, can impact the behaviors of OSF.

In addition to this post, Mike has also published a blog post today that overviews the overall OSF ontology modularization and architecture.

Continue reading “Role and Use of Ontologies in the Open Semantic Framework” →

Moving Projects from Google Code to GitHub

Frederick Giasson
Last week we slowly migrated Structured Dynamics‘ Google Code Projects to GitHub.We have been thinking about moving to GitHub for some time now, but we only wanted to move projects to it if no prior history and commits were dropped in the process. One motivation for the possible change has been the seeming lack of support by Google for certain long-standing services: we are seeing disturbing trends across a number of existing services. We also needed a migration process that would work with all of our various projects, without losing a trunk, branch, tag or commits (and their related comments).

It was not until recently that I found a workable process. Other people have successfully migrated Google Code SVN projects to GitHub, but I had yet to find a consolidated guide to do it. It is for this last reason that I write this blog post: to help people, if they desire, to move projects from Google Code to GitHub.

Moving from Google Code to GitHub

The protocol outlined below may appear complex, but it looks more intimidating than it really is. Moving a project takes about two to five minutes once your GitHub account and your migration computer is properly configured.

You need four things to move a Google Code SVN project to GitHub:

  1. A Google Code project to move
  2. A GitHub user account
  3. SSH keys, and
  4. A migration computer that is configured to migrate the project from Google Code to GitHub. (in this tutorial, we will use a Ubuntu server; but any other Linux/Windows/Mac computer, properly configured, should do the job)

Create GitHub Account

If you don’t already own a GitHub account, the first step is to create one here.

Create & Configure SSH Keys

Once your account has been created, you have to create and setup the SSH keys that you will use to commit the code into the Git Repository on GitHub:

  1. Go to the SSH Keys Registration page of your account
  2. If you already have a key, then add it to this page, otherwise read this manual to learn how to generate one

Configure Migration Server

The next step is to configure the computer that will be used to migrate the project. For this tutorial, I use a Ubuntu server to do the migration, but any Windows, Linux or Mac computer should do the job if properly configured.

The first step is to install Git and Ruby on that computer:

[cc lang=’bash’ line_numbers=’true’] sudo apt-get install git-core git-svn ruby rubygems[/cc]

To perform the migration of a Google Code SVN project to GitHub, we are using a Ruby application called svn2git that is now developed by Kevin Menard. The next step is to install svn2git on that computer:

[cc lang=’bash’ line_numbers=’true’] sudo gem install svn2git –source http://gemcutter.org [/cc]

Migrate Project

Before migrating your project, you have to link the Google Code committers to GitHub accounts. This is done by populating a simple text file that will be given as input to svn2git.

Open the authors.txt file into a temporary folder:

[cc lang=’bash’ line_numbers=’true’] sudo vim /tmp/authors.txt[/cc]

Then, for each author, you have to add the mapping between their Google Code and GitHub accounts. If a Google Code committer does not exist on GitHub, then you should map it to your own GitHub account.

[cc lang=’text’ line_numbers=’true’]
[raw]
(no author) = Frederick Giasson
fred@f…com = Frederick Giasson
[/raw]
[/cc]

The format of this authors.txt file is:

[cc lang=’text’ line_numbers=’true’ ][raw] Google-Account-Username = Name-Of-Author-On-GitHub (no author) mapping. This link is required for every authors.txt file. This placeholder is used to map the initial commit performed by the Google Code system. (When Google Code initializes a new project, it uses that username for creating the first commit of any project.)

When you are done, save the file.

Now that set up is complete, you are ready to migrate your project. First, let’s create the folder that will be used to checkout the SVN project on the server, and then to push it on GitHub.

[cc lang=’bash’ line_numbers=’true’]
cd /tmp/
mkdir myproject
cd myproject
[/cc]

In this tutorial, we have a normal migration scenario. However, your migration scenario may differ from this one. It is why I would suggest you check out the different scenarios that are supported by svn2git document. Change the following command accordingly. Let’s migrate the Google Code SVN Project into the local Git repository:

[cc lang=’bash’ line_numbers=’true’] /var/lib/gems/1.8/bin/svn2git http://myproject.googlecode.com/svn –authors /tmp/authors.txt –verbose [/cc]

Make sure that no errors have been reported during the process. If it is the case, then refer to the Possible Errors and Fixes section below to troubleshoot your issue.

The next step is to create a new GitHub repository where to migrate the SVN project. Go to this GitHub page to create your new repository. Then you have to configure Git to add a remote link, from the local Git repository you created on your migration computer, to this remote GitHub repository:

[cc lang=’bash’ line_numbers=’true’] git remote add origin [email protected]:you-github-username/myproject.git[/cc]

Finally, let’s push the local Git repository master, branches and tags to GitHub. The first thing to push onto GitHub is the SVN’s trunk. It is done by running that command:

[cc lang=’bash’ line_numbers=’true’] git push -u origin master[/cc]

Then, if your project has multiple branches and tags, you can push them, one by one, using the same command. However, you will have to replace master by the name of that branch or tag. If you don’t know what is the exact name of these branches or tags, you can easily list all of them using this Git command:

[cc lang=’bash’ line_numbers=’true’] git show-ref[/cc]

Once you have progressed through all branches and tags, you are done. If you take a look at your GitHub project’s page, you should see that the trunk, branches, tags and commits are now properly imported into that project.

Possible Errors And Fixes

Fatal Error: Not a valid object name

There are a few things that can go wrong while trying to migrate your project(s).

One of the errors I experienced is a "fatal" error message "Not a valid object name". To fix this, we have to fix a line of code in svn2git. Open the migration.rb file. Check around the line 227 for the method fix_branches(). Remove the first line of that method, and replace the second one by:

[cc lang=’ruby’ line_numbers=’true’][raw] svn_branches = @remote.find_all { |b| [email protected]?(b) && b.strip =~ %r{^svn\/} }[/raw][/cc]

Error: author not existing

While running the svn2git application, the process may finish prematurely. If you check the output, you may see that it can’t find the match for an author. What you will have to do is to add that author to your authors file and re-run svn2git. Otherwise you won’t be able to fully migrate the project.

I’m not quite sure why these minor glitches occurred during my initial migrate, but with the simple fixes above you should be good to go.

Open Sources Projects As A Pool Of Resources

Frederick Giasson
In a previous blog post, I wrote about how Open Source may be unnatural, and even counter intuitive, to many people. However, that really begs some questions evident with my current company’s strategy.

Why have Mike Bergman and I chosen to develop no less than three major open source projects (structWSF, conStruct and the Semantic Components), encompassing more than 100 000 lines of new code and leveraging between 30 to 50 other open source software and libraries? Why have we open sourced all our software? Why has open source formed the core business strategy of Structured Dynamics in the last three years? How have we been able to profitably sustain the company, even in the midst of the global economic crisis that began in 2008?

I will try to answer these questions in this blog post, perhaps even providing some guidance for newer startups that may follow behind us.

Why Open Sourcing?

Why did Structured Dynamics chose to open source all of its software? There are multiple reasons why people and businesses choose to go open source. For some, it is because they think that it is where the market place is moving. For others it is because they think that a community will emerge around their effort, and then get free resources that improve the piece of software. Some think that their software will promptly be reviewed by professional programmer. Others may think that their system will become more secure. Etc.

For Structured Dynamics the reason why we choose to go open source is somewhat different:

We perceived that by open sourcing our complete software stack we could bootstrap the company without any external investment.

Making a Living out of Open Source Projects

There are multiple ways to do a living from an open source project:

  • Doing consultancy work related to the project
  • Implementing the software(s) into clients’ computer environment(s)
  • Selling training classes
  • Selling support contracts
  • Selling maintenance contracts
  • Selling hosted instances of the software (the SaaS model for one)
  • Selling development time to improve some part(s) of the software
  • Creating conferences around their open source projects
  • Selling proprietary extensions
  • I am probably missing a few, so please add them in a comment section below, and I will make sure to add them to this list.

Depending on the software you are developing, and depending on the business plan of your company, you may be doing one — or multiple — of these things to generate some money from your open source projects.

At Structured Dynamics we are doing some of them: we do get consultancy contracts related to the Open Semantic Framework and we do implement OSF in our clients’ computer environments.

But, more importantly, we are also doing development contracts related to the framework. In fact, each project we are working on is quite different. Our major projects involve companies that reside in totally different domains, have different needs and need to accommodate different kinds of users. However, most of the projects share the same core needs, and all of them advance the core technology in ways meaningful to our vision. We choose our customers — and , of course, vice versa — based on a true sense of partnership wherein both parties have their objectives furthered.

Let’s see how we use these relationships to drive the development of the Open Semantic Framework.

Open Source Project as a Pool of Resources

In the last three years, Structured Dynamics has attracted multiple companies and organizations that share our vision, and which are willing to invest in the Open Semantic Framework open source project. (See Mike’s recent post on business development for a bit more on that aspect of things.) Each of these clients did want to use the OSF framework for their own needs. However, each of them did want to do something special that was not currently implemented in the framework.

What we created in these three years is a pool of resources that we used to develop the framework such that it accommodates the needs of each of our clients. Each of our clients then becomes a participant to the shared pool of innovation. Our clients have been willing to invest in the open source framework because they need their own features and because they know that they will benefit from what other participants of the pool will invest themselves down the road.

In that scenario, we are the managers of a pool of resources. We have the vision of where we want the framework to go, we know the roadmap of the project and we know the needs of each participant (our clients). What we do is to try to optimize the resources we get from each of our clients by developing the framework such that it can accommodate as broad of a spectrum of participants as possible. Then, we seek to find new participants that have some needs that will help us continue to develop the next steps of the roadmap. In this manner, we Jacob’s Ladder our existing work to increase the capabilities for later clients, but earlier clients still benefit because they can upgrade to the later improvements. This is a self-sustaining model to continue to move the development of the framework forward.

By finding new clients, what we do is to give a return on investment to the other pool participants. Most of the new features that we develop for these new clients will benefit the other participants to the pool and will create new possibilities for them without any additional investment. All of our first clients have implemented what other participants later invest into the pool, thus crystallizing and augmenting their return on investment by using these new features.

Open Source is Not Just About Software

Open Source is not just about pieces of code, and this is quite important to understand. What we have open sourced with the Open Semantic Framework is much more than a series of code sources. We open sourced the entire framework:

  1. The source codes
  2. The documentation
  3. The processes
  4. The methodologies

We term this comprehensive approach our total open solution.

This distinction with other open source projects is an essential differentiator with our approach. We choose to open source all of the pieces related to the framework. What drove this decision is a simple sentence that shows our philosophy behind it:

“We’re Successful When We’re Not Needed”

If the APIs, processes and methodologies are not properly documented, it means that we would certainly be needed by our clients, which would mean that we failed to open source our solution. But since we are working to open source our code, our processes and our methodologies, we are on the way to successfully open source the Open Semantic Framework since we won’t be needed by our clients.

This business approach is not as crazy as it sounds. We are free to work on new and important innovations, and are not basing our company culture on dependency and a constant drain by our customers. I know, it does not sound like Larry Ellison, but sounds good to us and our clients. It is certainly not a maximum revenue objective built on the backs of individual clients.

Our life is more fun and our clients trust us with new stuff. Further, each step of the way, we are able to leverage our own framework for unbelievable productivity in what we deliver for the money. But that is a topic for another day.

We think Structured Dynamics’ business approach is a contemporary winning strategy. Our customers get good and advanced capabilities at low cost and risk, while we get to work on innovative extensions that are raising the semantic baseline for the marketplace. Who knows if we will always continue this path, but for now it is leading to sustained development and market growth for open semantic frameworks, including our own OSF.

 

 

Unnatural Open Source

Frederick Giasson
I have never been an open source software advocate. In fact, like most people, I always wondered how companies could find a business advantage in developing open source softwares and how they could make money out of it to grow. It is nice to have open source softwares, but it is hard to imagine how you could justify putting thousands of hours in open source software projects if it is not only by passion.

In this post I will explain what I think is the main factor that put people, businesses and organizations on guard when come the time to think about open source softwares. In fact, I think it has much more to do with our nature: how we naturally are as human being, and much less to do with any real business related factors.

In a follow-up blog post, I will explain how Structured Dynamics embraced open source software, how we developed the company around the concept, and how we are managing the development of our project such that it benefits all our clients along with the company. But first, let’s try to figure out why much people are suspicious regarding open source softwares.

The Fear

“I must not fear. Fear is the mind-killer. Fear is the little-death that brings total obliteration. I will face my fear. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the fear has gone there will be nothing. Only I will remain.”

– Dune, Frank Herbert

Have you ever heard someone telling you:

I found an incredible business idea! I am pretty sure that I am the first one to think about that. I will get some good money down the road!

Then, you naturally asked for more information about this great idea! And then the answer you got was something like:

Hooo! But I can’t tell you, this is really secret right now, at least until everything is ready to go.

Does this sound familiar? I does to me. I hear it often. But, why does people react that way? It is simply by fear: fearing that someone “steal” their ideas, start a company based on them, build projects or services that implemented them, and get rich while you are flipping burgers at McDonald’s.

To me, this is the main reason why people, organizations and businesses are suspicious regarding open source software: because of fear; fear of loosing something they don’t even have.

But the question is: is that rational? From my experience, and my understanding of how things works, I can certainly say that it is not. This way of thinking is not rational because it doesn’t take into account a few things:

  • The ability of others to do something with your ideas
  • The ability of others to have the vision you have for your ideas
  • The willingness of others to spend all their time and energy to make these ideas working
  • [raw]People tend to do what they want to do, and not what others wants­[/raw]

The same behavior seems to happen with open source projects. When I am explaining to people what we are doing, one of the first reaction is: why your work is open and free? Don’t you fear that someone steal your project and ideas? How can you make money if it is free, people will just run with it for themselves no?

The simple answer to all these question is: no. No we don’t feature that anybody steal our projects and ideas just by cloning them from the source control. We don’t because of the four reasons listed above. We don’t because we trust our vision and our abilities to implement it in our various open source projects. And yes we can sustain the company pretty well with these projects and it is what I will cover in my following blog post.

Conclusion

Non-Open Source softwares are just like when someone has a business idea “for the next big thing” and that doesn’t want to share it with anybody else because he think that someone will take that idea and run with it by himself. In fact, it is quite the opposite. I learned with experience that there is only one person (or organization) that can make such a great idea a relative success: the person (or organization) that lives for that idea. An idea is just an idea, and has nothing great in it, until it gets implemented, until the idea lives by itself, propelled by it most dedicated advocate: its creators and their boundless enthusiasm. Any idea would fail without this… and would worth nothing; it would just be an idea.

Getting Data Out of MyPeg.ca using structWSF Endpoints

Frederick Giasson
A few weeks ago I presented the new MyPeg.ca community indicators web portal for Winnipeg’s citizens. I explained how in MyPeg.ca we leverage Structured Dynamics’ semantic technologies stack (akaThe Semantic Muffin). Today’s blog post explains one facet of the project that shows how external agents (people, services, software, etc.) can interact with the system’s indicator datasets using the structWSF web service endpoints.Since this post focuses only on data export, I suggest you read the structWSF Web Services Tutorial for a complete overview of how the endpoints architecture works.

Merging Pipes

Two Main structWSF Characteristics: Accessibility & Management

structWSF is a set of 22 web service endpoints that lets you integrate data from different sources, manage that integrated data, and publish it via different communication channels such as web pages, software applications, etc.

Obviously, the main characteristic of this framework is that everything is a web service. This means that all functionality of the system can be accessed from anywhere on the Internet. However, this doesn’t mean that everything is open like a snack-bar. In fact, there are two levels of accessibility: (1) access to the web service endpoint’s URL, and (2) access to the content of datasets hosted on structWSF. Depending on the usecase, people could restrict the direct access to the web service endpoint(s) by properly configuring their web server, others could choose to let anyone access the endpoints, but would restrict the access to the dataset(s) hosted by structWSF. In case of MyPeg.ca, the sponsor chose to open the access to their web service endpoints and datasets.

Just by surfing on the MyPeg.ca portal, you are already leveraging these endpoints in multiple different ways. First, each time you generate a browse or a search Web page, you are telling the web server to send multiple queries to different endpoints; then the web page’s content will be populated with that information and presented to you. But, each time you click on an explorer node, your web browser is also sending queries to exactly the same web service endpoints. So, in one case a PHP script acts to query the endpoints; and, in other cases, a Flash Semantic Component does. Depending, all structWSF data can be accessed from quite different environments.

The other main characteristic of structWSF is that any kind of data can be imported in, and exported out, of the system. structWSF leverages RDF (Resource Description Framework) as the canonical data format that can be used to express any other formats. It is because of the usage of RDF that structWSF can act as an effective ETL (Extract, transform, load) system. Depending on the web service endpoint, the output formats currently supported by most of the endpoints are:

But the architecture of the web service endpoints can easily accommodate other formats if needed for a specific usecase.

Getting Data Out Of MyPeg.ca

Now, how can you get data out of MyPeg.ca? There are really two methods. This blog post discusses the CRUD: Read, Browse and Search web service endpoints. In my next blog post, I will focus on using the SPARQL web service endpoint to do the same.

All of the query examples in this blog post will use a tool called Curl to send the queries and to get back the resultsets. I encourage you to download and use that tool to test these endpoints and to gain a feeling for how it works. Also note that only the first record of each resultset is recorded below (of course, the actual results include all records).

Browse

The Browse web service endpoint is used to return lists of records. These records can also be filtered according to their provenance (dataset), type and the attributes that describe them. Now, let’s see how you can use this web service to get data out of MyPeg.ca.

First, there are three datasets available to the public:

  1. Well-being Indicators (http://www.mypeg.ca/wsf/datasets/258/)
  2. Stories (http://www.mypeg.ca/wsf/datasets/272/)
  3. PEG Framework (http://www.mypeg.ca/wsf/datasets/249/)

The resultsets can be serialized using one of these four different formats:

  • text/xml (structXML)
  • application/json (structXML in JSON)
  • application/rdf+xml (RDF/XML)
  • application/rdf+n3 (RDF/N3)

Note: if one of your desired formats is not directly available at the endpoint level, you can always use one of the converter web service endpoints such as: commON, irJSON or TSV/CSV.

Get the first 10 results of the Stories dataset in structXML

Query:

[cc lang=’text’ line_numbers=’false’]curl -H “Accept: text/xml” “http://www.mypeg.ca/ws/browse/” -d “attributes=all&types=all&datasets=http%3A%2F%2Fwww.mypeg.ca%2Fwsf%2Fdatasets%2F272%2F&items=10&page=0&inference=on&include_aggregates=true”[/cc]

StructXML resultset:

[cc lang=’xml’ line_numbers=’false’ escaped=’true’]

<?xml version=”1.0″ encoding=”utf-8″?>
<resultset>
<prefix entity=”owl” uri=”http://www.w3.org/2002/07/owl#”/>
<prefix entity=”rdf” uri=”http://www.w3.org/1999/02/22-rdf-syntax-ns#”/>
<prefix entity=”rdfs” uri=”http://www.w3.org/2000/01/rdf-schema#”/>
<prefix entity=”wsf” uri=”http://purl.org/ontology/wsf#”/>
<subject type=”http://purl.org/ontology/muni#Story” uri=”http://www.mypeg.ca/wsf/datasets/272/resource/AgeOpportunity”>
<predicate type=”http://purl.org/dc/terms/isPartOf”>
<object type=”http://rdfs.org/ns/void#Dataset” uri=”http://www.mypeg.ca/wsf/datasets/272/”/>
</predicate>
<predicate type=”http://purl.org/ontology/iron#prefLabel”>
<object type=”rdfs:Literal”>Age &amp; Opportunity</object>
</predicate>
<predicate type=”http://purl.org/dc/terms/created”>
<object type=”rdfs:Literal”>2010-10-28T19:38:58+00:00</object>
</predicate>
<predicate type=”http://purl.org/ontology/bibo/abstract”>
<object type=”rdfs:Literal”>Amanda Macrae, Deborah Lorteau and Stacey Miller work for Age and Opportunity.
The majority of clients are older adults living at lower socio economic status. When addressing the housing issue they say, “In a nutshell, it’s dire.” There is simply not enou…</object>
</predicate>
<predicate type=”http://purl.org/ontology/peg#interviewee”>
<object type=”rdfs:Literal”>Amanda Macrae, Deborah Lorteau, Stacey Miller</object>
</predicate>
<predicate type=”http://purl.org/ontology/peg#interviewer”>
<object type=”rdfs:Literal”>Molly Johnson</object>
</predicate>
<predicate type=”http://purl.org/ontology/peg#storyRelatedAgencyProgram”>
<object type=”rdfs:Literal”>Age &amp; Opportunity</object>
</predicate>
<predicate type=”http://purl.org/ontology/sco#storyAnnotatedTextUri”>
<object>http://www.mypeg.ca/scones/AgeOpportunity.xml</object>
</predicate>
<predicate type=”http://purl.org/ontology/sco#storyTextUri”>
<object type=”rdfs:Literal”>http://www.mypeg.ca/scones/AgeOpportunity.txt</object>
</predicate>
</subject>
</resultset>

[/cc]

Get the 10 first results from all datasets that are records of type Neighborhoods in RDF/XML

Query:

[cc lang=’text’ line_numbers=’false’]curl -H “Accept: application/rdf+xml ” “http://www.mypeg.ca/ws/browse/” -d “attributes=all& type=http%3A%2F%2Fpurl.org%2Fontology%2Fpeg%23Neighborhood &datasets=all&items=10&page=0&inference=on&include_aggregates=true”[/cc]

RDF/XML resultset:

[cc lang=’xml’ line_numbers=’false’ escaped=’true’]

<?xml version=”1.0″?>
<rdf:RDF  xmlns:owl=”http://www.w3.org/2002/07/owl#” xmlns:rdf=”http://www.w3.org/1999/02/22-rdf-syntax-ns#” xmlns:rdfs=”http://www.w3.org/2000/01/rdf-schema#” xmlns:wsf=”http://purl.org/ontology/wsf#” xmlns:ns0=”http://purl.org/ontology/peg#” xmlns:ns1=”http://purl.org/dc/terms/” xmlns:ns2=”http://purl.org/ontology/iron#” xmlns:ns3=”” xmlns:ns4=”http://purl.org/dc/elements/1.1/” xmlns:ns5=”http://purl.org/ontology/aggregate#”>

<ns0:Component rdf:about=”http://purl.org/ontology/peg/framework#Safety”>
<ns1:isPartOf rdf:resource=”http://www.mypeg.ca/wsf/datasets/249/” />
<ns2:prefLabel>Safety</ns2:prefLabel>
<ns2:altLabel>safety</ns2:altLabel>
<ns3:>safety</ns3:>
<ns4:description>Safety is the state of being “safe”, the condition of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or other types or consequences of failure, damage, error, accidents, harm or any other event which could be considered non-desirable.</ns4:description>
<rdfs:comment>Includes the idea of safety prevention</rdfs:comment>
<rdfs:seeAlso>http://en.wikipedia.org/wiki/Safety</rdfs:seeAlso>
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#HouseholdIncome” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#LowIncomeCutOffAfterTax” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#MarketBasketMeasure” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#ParticipationInSportsAndRecreation” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#MaternalSocialIsolation” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#PersonalSafety” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#EarlyDevelopmentInstrument” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#HighSchoolGraduationRate” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#LongTermUnemployment” />
<ns0:hasIndicator rdf:resource=”http://purl.org/ontology/peg/framework#TeenageBirths” />
<ns0:isComponentOf rdf:resource=”http://purl.org/ontology/peg/framework#BasicNeeds” />
<ns0:isComponentOf rdf:resource=”http://purl.org/ontology/peg/framework#Poverty” />
</ns0:Component>
</rdf:RDF>

[/cc]

Search

The Search web service endpoint is also used to return lists of records. These records should match a search string and can also be filtered according to their provenance (dataset), type and the attributes that describe them.

The same mime types and datasets as the ones for the Browse web service are available for the Search endpoint.

Searching for records with the keyword “poverty” and get resultsets in RDF/N3

Query:

[cc lang=’text’ line_numbers=’false’]curl -H “Accept: application/rdf+n3” “http://www.mypeg.ca/ws/search/” -d “query=poverty&datasets=all&items=10&page=0&inference=on&include_aggregates=true”[/cc]

RDF/N3 resultset:

[cc lang=’text’ line_numbers=’false’ escaped=’true’]

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix wsf: <http://purl.org/ontology/wsf#> .

<http://purl.org/ontology/peg/framework#Poverty> a <http://purl.org/ontology/peg#CrossCuttingIssue> ;
<http://purl.org/dc/terms/isPartOf> <http://www.mypeg.ca/wsf/datasets/249/> ;
<http://purl.org/ontology/iron#prefLabel> “””Poverty””” ;
<http://purl.org/dc/elements/1.1/description> “””Poverty is not having the sufficient resources, capabilities, choices, security and power necessary to enjoy an adequate standard of living.  Poverty includes much more than a lack of money.  It includes being excluded from ordinary living patterns, customs and activities.  Consequently, people living in poverty are often unable to participate fully in their communities or to reach their full potential.””” ;
<http://www.w3.org/2000/01/rdf-schema#seeAlso> “””http://en.wikipedia.org/wiki/Poverty””” .

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CRUD: Read

The Browse and Search web service endpoints are really used to find lists of records according to some provided criteria. However, the complete description of these records is not returned by these endpoints, but only the information necessary to create the proper list to display to users in a user interface. So, to get the complete description of a record (or multiples thereof), you have to use the CRUD: Read web service endpoint. Also, sometimes you may get a reference to a record hosted on a structWSF node, then CRUD: Read is the way to get its full description.

Get the full description of the Ida story in irJSON

Query:

[cc lang=’text’ line_numbers=’false’]curl -H “Accept: application/iron+json” “http://www.mypeg.ca/ws/crud/read/?uri=http%3A%2F%2Fwww.mypeg.ca%2Fwsf%2Fdatasets%2F272%2Fresource%2FIda&dataset=http%3A%2F%2Fwww.mypeg.ca%2Fwsf%2Fdatasets%2F272%2F&include_reification=true&include_linksback=false[/cc]

irJSON resulset:

[cc lang=’javascript’ line_numbers=’false’ escaped=’true’]

{
“dataset”: {
“linkage”: [
{
“linkedType”: “application/rdf+xml”,
“attributeList”: {
“created”: {
“mapTo”: “http://purl.org/dc/terms/created”
},
“isAbout”: {
“mapTo”: “http://umbel.org/umbel#isAbout”
},
“prefLabel”: {
“mapTo”: “http://purl.org/ontology/iron#prefLabel”
},
“interviewee”: {
“mapTo”: “http://purl.org/ontology/peg#interviewee”
},
“interviewer”: {
“mapTo”: “http://purl.org/ontology/peg#interviewer”
},
“abstract”: {
“mapTo”: “http://purl.org/ontology/bibo/abstract”
},
“storyVideoAudio”: {
“mapTo”: “http://purl.org/ontology/peg#storyVideoAudio”
},
“storyAnnotatedTextUri”: {
“mapTo”: “http://purl.org/ontology/sco#storyAnnotatedTextUri”
},
“storyTextUri”: {
“mapTo”: “http://purl.org/ontology/sco#storyTextUri”
}
},
“typeList”: {
“Story”: {
“mapTo”: “http://purl.org/ontology/muni#Story”
}
}
}
]},
“recordList”: [
{
“id”: “http://www.mypeg.ca/wsf/datasets/272/resource/Ida”,
“type”: “Story”,
“created”: “2010-10-28T18:11:27+00:00”,
“isAbout”: [
{
“ref”: “@@http://purl.org/ontology/peg/framework#EducationAndLearning”
},
{
“ref”: “@@http://purl.org/ontology/peg/framework#Health”
},
{
“ref”: “@@http://purl.org/ontology/peg/framework#Program”
},
{
“ref”: “@@http://purl.org/ontology/peg/framework#Income”
},
{
“ref”: “@@http://purl.org/ontology/peg/framework#Poverty”
}     ],
“prefLabel”: “Ida”,
“interviewee”: “Ida”,
“interviewer”: “Christa Rust”,
“abstract”: “‘Poverty is earning just enough to get by; never having money for extras.’\n\nIda is the mother of two grown children, eight years apart.  She lives in a small bachelor suite, which costs her $428 per month, or 62% of her income.  She volunteers twice a we…”,
“storyVideoAudio”: “http://www.youtube.com/v/0zIqtYhiHfM”,
“storyAnnotatedTextUri”: “http://www.mypeg.ca/scones/Ida.xml”,
“storyTextUri”: “http://www.mypeg.ca/scones/Ida.txt”
}
]
}

[/cc]

Get Well-Being record description with linkbacks in RDF+N3

The characteristic of this query is that I enabled the “include_linksback” parameter. This returns a reference to all the records, in the datasets hosted on the structWSF node, that refers to that target record.

Query:

[cc lang=’text’ line_numbers=’false’]curl -H “Accept: application/rdf+n3” “http://www.mypeg.ca/ws/crud/read/?uri=http%3A%2F%2Fpurl.org%2Fontology%2Fpeg%2Fframework%23WellBeing&datast=http%3A%2F%2Fwww.mypeg.ca%2Fwsf%2Fdatasets%2F249%2F&registered_ip=self%3A%3A0&include_reification=true&include_linksback=true”[/cc]

RDF+N3 resultset:

[cc lang=’text’ line_numbers=’false’ escaped=’true’]

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

<http://purl.org/ontology/peg/framework#WellBeing> a <http://purl.org/ontology/peg/framework#WellBeing> ;
<http://purl.org/ontology/iron#prefLabel> “””Well-being””” ;
<http://purl.org/dc/elements/1.1/description> “””Well-being refers to the general quality of life experienced by individuals and communities. The elements of wellbeing include: the ability to meet basic needs, the economy, health, the built environment, governance, education and learning, the natural environment, and social vitality.””” ;
<http://purl.org/ontology/sco#displayComponent> <http://purl.org/ontology/sco#sRelationBrowser> .

<http://purl.org/ontology/peg/framework#WellBeing> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#Economy> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#Governance> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#BuiltEnvironment> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#NaturalEnvironment> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#SocialVitality> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#BasicNeeds> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#EducationAndLearning> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

<http://purl.org/ontology/peg/framework#Health> a <http://www.w3.org/2002/07/owl#Thing> ;
<http://purl.org/ontology/peg#isThemeOf> <http://purl.org/ontology/peg/framework#WellBeing> .

[/cc]

General Endpoint Parameters

The general parameters available for each of these web services is provided in their respective TechWiki documentation. For that detailed information, see the Browse, Search, or CRUD: Read articles.

Conclusion

As you can see, agents can get different kinds of data from the MyPeg.ca portal by querying a set of web service endpoints. This is one way to get data out of the system. These data can then be accessed for indexing in other systems, for direct use, or for dynamic applications like browsing the nodes in the explorer.

This is one of the ways to get data out of the system. A user can also export that same information from the Export features on the Browse, Search and Record View pages. Also, other methods will be explained in the next blog posts from this MyPeg.ca series.

All in all, this shows how effective structWSF can be to integrate, manage and publish a wide range of data in different data formats. It also shows how completely different parts of your software architecture can leverage your information, the way you want, from anywhere on the Internet.