The official announcement was sent out yesterday, kicking off the 30 day review. The announcement includes links to the public review documents for the Core Protocol, Atom, and JSON specifications, and instructions for submitting feedback through the mailing list. Note that all comments submitted to OASIS are subject to the OASIS Feedback License.

This is an exciting milestone for OData and we need your help! The public review is your opportunity to provide input into OData version 4.0, so please review the latest documents and send us feedback as soon as possible, but no later than the close of this public review period, June 2, 2013.

Thank you in advance for your feedback!

With the introduction of data and metadata annotations to OData version 3.0, developers can now define common vocabularies for things like Sales (with Customers, SalesOrder, Product, etc.), Movies (with Title, Actor, Director, ....), Calendars (with Event, Venue, …), etc. Of course, such vocabularies are only useful to the extent that they are shared across a broad range of clients and services.

Over the past  year, schema.org has been defining common schemas to make it easier for search engines to find and understand data on the web. Whenever we talk about shared Vocabularies in OData we inevitably get asked about the relationship of common ontologies expressed through OData Vocabularies to the work going on in schema.org.

I am happy to share that, through ongoing discussions with the members of schema.org, we have agreed that defining common OData Vocabulary encodings of the schema.org schemas is a benefit to both technologies. Sharing a common vocabulary even across different encodings like OData, RDFa 1.1, and Microdata, facilitates a common understanding and even possible transformation of data across those encodings. Toward that end we have jointly posted a discussion paper on the Web Schemas wiki on the use of schema.org schemas within OData.

From Dan Brickley's blog post on new developments around schema.org:

"We are also pleased to announce today a discussion paper on the use of OData and Schema.org, posted in the Web Schemas wiki. OData defines a RESTful interface for working with data on the Web. The newest version of OData allows service developers and third parties to annotate data or metadata exposed by an OData Service. Defining common OData Vocabulary encodings of the schema.org schemas facilitates the understanding and even transformation of data across these different encodings."

Feel free to add comments to Dan's post, or send us feedback on the odata.org mailing list.

Exciting times for OData!

-Mike

I’m happy to announce that Citrix, IBM, Microsoft, Progress Software, SAP and WSO2 are jointly submitting a proposal for the standardization of OData to OASIS.

While the OASIS OData Technical Committee will standardize OData, the great collaboration will continue in the odata.org community to grow the library of producers and consumers and, share implementation and Interop experiences, etc.

The starting point for the proposal is the current OData v3 specification plus a number of proposed extensions that use the protocol extensibility points to add functionality without having to increase the footprint of the core specification.

We often have discussions within the team, with developers out there and the community about what OData can and cannot do and whether we should add this or that feature. In that context we always come back to the same few principles that guide the design of OData: the main value of this technology is not any particular design choice but the fact that enough people agree to the same pattern, thus removing friction from sharing data across independent producers and consumers. For that to work the protocol must remain simple for simple cases, cover more sophisticated cases reasonably well and avoid inventing stuff as much as possible.

With interoperability front and center in OData we saw more and more technology stacks that started to work with it. Now there are a number of companies that use OData in their products to ensure the data they manage is easily accessible beyond the boundaries of their applications. Many of these companies regularly collaborate on the ongoing design effort for OData. While so far we’ve run the OData design process as transparently as we could (sharing designs, taking feedback through the odata.org blog and distribution list, etc.), we are at a point where the level of adoption and the scale at which organizations are betting on OData require a more formal commitment to shared ownership of the design of this protocol.

We have a good amount of work ahead of us in the OASIS TC, but this is the first step. We’ll keep posting to this blog with updates as things progress.

We encourage others to get involved to learn more about the protocol and design decisions that were made in developing the protocol. Go to odata.org, check out the OData blog and join the OData mailing list (the instructions are on odata.org).  Join the OASIS OData TC and help us standardize the protocol!

We’re happy to see OData take this important step on the journey towards standardization. Thanks to all the folks out there that helped get OData this far.

-pablo

In April we shipped the OData version 3 along with the 5.0 release of WCF Data Services. To make it easier for you discover the new features and for us to show you some of them, we’re now making available the OData demo services which use the OData V3 protocol.

The new services are hosted side by side with old demo services which we didn’t change. The new demo services are using the WCF Data Services 5.0.1-rc release currently, and we will update them to the newer version once it becomes available.

There are 3 demo services:

The read-only Demo service, which has an updated model to use some V3 features as described below, is hosted here:

http://services.odata.org/V3/OData/OData.svc/

The read-write Demo service, which is the exact same model as the read-only Demo service including new V3 features, is hosted here:

http://services.odata.org/V3/(S(readwrite))/OData/OData.svc/

The read-only Northwind service, which is the exact same model as the existing Northwind service, is hosted here:

http://services.odata.org/V3/Northwind/Northwind.svc/

Here are the V3 features we’ve enabled so far.

Actions

The Product type has a Discount action on it which takes a single parameter discountPercentage of type Edm.Int32. The action takes the Price of the product it’s applied to and decreases it by the percentage specified by the parameter. For example:

  GET http://services.odata.org/V3/(S(plcxuejnllfvrrecpvqbehxz))/OData/OData.svc/Products(1)

Will return a product with Price: 3.5

  POST http://services.odata.org/V3/(S(plcxuejnllfvrrecpvqbehxz))/OData/OData.svc/Products(1)/Discount HTTP/1.1
Content-Type: application/json;odata=verbose

{ "discountPercentage": 25 }

The response should be 204 No Content.

And now again

  GET http://services.odata.org/V3/(S(plcxuejnllfvrrecpvqbehxz))/OData/OData.svc/Products(1)

Returns a product with Price: 2.625

Spatial

The Supplier type has a property Location which is of type Edm.GeographyPoint. You can see it here:

http://services.odata.org/V3/OData/OData.svc/Suppliers(0)

Any and All

The service now supports any and all operators. For example:

http://services.odata.org/V3/OData/OData.svc/Categories?$filter=Products/any(p: p/Rating ge 4)

Inheritance support

You can now address properties on derived types. The demo service doesn’t have a sample property like that yet, but you can try the new URL syntax with type cast anyway:

http://services.odata.org/V3/OData/OData.svc/Products/ODataDemo.Product

Patch support

You can send PATCH requests instead of MERGE. The behavior is identical otherwise.

Prefer header support

You can specify a Prefer header in create or update requests and ask the server to either omit or include the payload. For example:

  PATCH http://services.odata.org/V3/(S(plcxuejnllfvrrecpvqbehxz))/OData/OData.svc/Products(1) HTTP/1.1
Accept: application/json;odata=verbose
Content-Type: application/json;odata=verbose
Prefer: return-content
DataServiceVersion: 3.0;

  { "Price": "3.5" }

Responds with (trimmed for readability):

  HTTP/1.1 200 OK
Content-Type: application/json;odata=verbose;charset=utf-8
Preference-Applied: return-content
DataServiceVersion: 3.0;

{"d":{
"__metadata":{…},
…
"ID":1,
"Name":"Milk",
"Description":"Low fat milk",
"ReleaseDate":"1995-10-01T00:00:00",
"DiscontinuedDate":null,
"Rating":3,
"Price":"3.5"
}}

Association links

Each navigation link can now also specify an association link which is the URL to manipulate the association with. For example this is a part of the ATOM payload for ~/Product(1):

<link
rel="http://schemas.microsoft.com/ado/2007/08/dataservices/related/Category"
type="application/atom+xml;type=entry"
title="Category"
href="Products(1)/Category" />
<link
rel="http://schemas.microsoft.com/ado/2007/08/dataservices/relatedlinks/Category"
type="application/xml"
title="Category"
href="Products(1)/$links/Category" />

We are working on adding more V3 features to the Demo service and we’ll be updating the service as we have them available.

Vitek Karas
Sr. Software Development Engineer, OData, Microsoft.

We recently put together a document that contains some of our thinking about JSON light as well as a whole slew of sample payloads. We would love to hear any feedback you have on the format; you can comment in the accompanying OneNote.

We will be accepting public feedback on JSON light until May 4, 2012. We will also provide a preview release of the JSON light bits via NuGet for interested parties.

JSON light at-a-glance: https://skydrive.live.com/redir.aspx?cid=0d23ed2816deea7b&resid=D23ED2816DEEA7B!966&parid=D23ED2816DEEA7B!106&authkey=!AAYCE2RUJccjhHk
Discussion: https://skydrive.live.com/redir.aspx?cid=0d23ed2816deea7b&page=view&resid=D23ED2816DEEA7B!967&parid=D23ED2816DEEA7B!106&authkey=!ABdrv3heWfQFY4Y

We had some great presentations

• Mike Pizzo had fun stories on the Evolution of OData. He talked about the open design approach that the OData team adopted from the very beginning and how it helped to bring the community on board. He concluded that OData design has benefited greatly from broad community participation.
• Pablo Castro and Alex James covered the new features that are coming as part of OData v3. OData v3 has ton of features that augment the RESTful story for OData. Features like vocabularies and functions provide the necessary extension points that enable implementers to go beyond what is offered in the core implementation and still be able to play within the OData ecosystem.
• Ralf Handl from SAP talked about how OData helped them achieve the vision for ‘Open Data’ – Any Environment, Any Platform, Any Experience. In later talks by SAP they showed some of their products that are powered by OData. In addition to the OData feeds they publish, they demonstrated client tools that enable developers to easily consume SAP OData feeds on the platform of their choice.
• Dana Gutride from Citrix walked through their experience of enabling OData in some of their products. OData’s standards-based approach, capabilities like type safety, and ease of access made it an obvious choice for their product.
• Webnodes presented how they integrated OData into their CMS system
• Eastbanc Technologies talked about their metropolitan transit visualization tool
• Viecore’s demoed its advanced decision support and control systems for the U.S. military
• APIgee’s Anant Jhingran gave more of a Zen talk; Anant hit few themes that are worth mentioning
  • If Data isn’t your core business, then you should give it away
  • Opportunity for OData community is immense – question is whether we’ll grab it
  • Data as an information halo surrounding core business is the OData opportunity
• Pablo Castro gave another talk titled ‘OData: The Good, the Bad, and the Ugly’, which focused on what things Microsoft has done right and wrong in implementing their OData stack (beer was served during this talk to ensure these points do not last long in people’s memory)

The first day ended with a delicious dinner at the Spitfire restaurant in Redmond.

On the second day of the meetup we used Open Space format (http://www.openspaceworld.org/) to encourage loosely-structured discussion. Through Arlo Belshee’s awesome coordination, we put together by the end of the first hour an exciting agenda for the rest of the day.

Some of the conversations that happened and themes that emerged:

• The topic of vocabularies sparked a great discussion, in which we were trying to decide what tools and communications media would best help groups create vocabularies and then advertise them to others. We also talked about whether there were vocabularies that were central enough to warrant definition by the OData community as a whole.
• SAP led a discussion exploring ways to model Analytical data (cubes) in OData, and meetup attendees had many good suggestions.
• There was a lot of talk about open source, ODataLib, and a shared query processor. Some people talked about porting ODataLib to other languages. Others discussed getting improvements folded back into existing projects, such as OData4J. We had several conversations about a query processor, and what form it could take. We even got into some architectural discussion about potential programming APIs.
• · We heard repeatedly that there isn’t enough marketing of OData to CIOs and other decision makers, and we discussed different ways to improve the odata.org website to make it more useful for the community.
• JSON Light came up several times. We kicked the tires around some of the current thinking and explored how that would interact with peoples’ existing implementations.

The two days were both educational and fun-filled, and they showed how big the OData community has grown in recent years. There was a strong interest from the attendees to do more of these community-driven events.

Asad Khan

OData Service Validation Tool  was updated with 5 new rules and the ground work for supporting OData v3 services:

• 4 new common rules
• 1 new entry rule
• Added version annotation to rules to differentiate rules by version
• Modified the rule selection engine to support rule version.
• Change rule engine API to support rule versions
• Changed database schema to log request and response headers
• Added a V3 checkbox for online and offline validation scenarios

This update brings the total number of rules in the validation tool to 152. You can see the list of the active rules here and the list of rules that are under development here.

Moreover, with this update the validation tool is positioned to support rules for v3 services for OData V3 payload validation.

Keep on  validating and let us know what you think either on the mailing list or on the discussions page on the Codeplex site.

• 6 new common rules
• 1 new entry rule

This rule update brings the total number of rules in the validation tool to 147. You can see the list of the active rules here and the list of rules that are under development here.