- From: Jocelyn Fournier <jocelyn.fournier@gmail.com>
- Date: Thu, 17 Apr 2014 21:03:11 +0200
- To: Jason Douglas <jasondouglas@google.com>, Jarno van Driel <jarno@quantumspork.nl>
- CC: Public Vocabs <public-vocabs@w3.org>
Le 17/04/2014 20:25, Jason Douglas a écrit : > Yup, that's messed up. Let's fix it! Hi, Note that examples regarding mainContentOfPage on schema.org are also misleading. E.g. : http://schema.org/Table => <meta itemprop="mainContentOfPage" content="true"/> I would have expected <div itemprop="mainContentOfPage" itemscope itemtype="http://schema.org/Table"> But I fully agree it would be much more usefull to have mainContentOfPage as a 'Thing' rather than 'WebPageElement' Jocelyn > > On Thu Apr 17 2014 at 11:15:43 AM, Jarno van Driel > <jarno@quantumspork.nl <mailto:jarno@quantumspork.nl>> wrote: > > "...if a relation is declared without an explicit subject, then the > subject will be assumed to be the current WebPage." > Got it. > > "It is legal for there to be multiple top-level entities." + > "Current clients make up their own heuristics for this..." > Brainfreeze! > How am I, as a developer, to deal with this? Does this mean I have > to somehow figure out which heuristics every parser/search engine > uses, to be able to have control or do I need to try to chain > everything together such that only one top-level entity is left? > > And how would I do this for a category page on for example an > eCommerce site. Which shows a range of Product entities on a > CollectionPage, which together form the main-content and where the > CollectionPage, for lack of a better term, only functions as a > 'wrapper' for the list of products. > > "we probably do need a mechanism for indicating the "primary entity" > of a webpage when there is one..." > One the reasons why I asked my questions is because I encounter > quite a lot of markup on websites where people use @mainContentPage > on entities like Product. Now @mainContentOfPage has the expected > type WebPageElement, but many aren't aware of this. And since there > is no property to indicate which entity is the primary one I > actually can completely understand they try to resolve it like this. > And frankly, I'm confused as well. > > > > On Thu, Apr 17, 2014 at 7:51 PM, Jason Douglas > <jasondouglas@google.com <mailto:jasondouglas@google.com>> wrote: > > It is legal for there to be multiple top-level entities. That > description of WebPage is not meant to imply anything about the > relationship of those top-level objects... all that is saying is > that if a relation is declared without an explicit subject, then > the subject will be assumed to be the current WebPage. > > That said, we probably do need a mechanism for indicating the > "primary entity" of a webpage when there is one. Current > clients make up their own heuristics for this, but I think it > would be better to have an explicit way of stating that. > > -jason > > > On Thu Apr 17 2014 at 10:41:47 AM, Jarno van Driel > <jarno@quantumspork.nl <mailto:jarno@quantumspork.nl>> wrote: > > I'm trying to understand semantic mechanisms better but am a > bit confused about schema.org/WebPage > <http://schema.org/WebPage> and I'd like to know how it works. > > Now it could well be I understand certain terminologies > wrong, so please bare with me and be so nice to correct me > when needed. > > 1] The description of http://schema.org/WebPage says: > "Every web page is implicitly assumed to be declared to be > of type WebPage, so the various properties about that > webpage, such as breadcrumb may be used. We recommend > explicit declaration if these properties are specified, but > if they are found outside of an itemscope, they will be > assumed to be about the page." > > code example: > <body itemscope itemtype="http://schema.org/WebPage"> > <!-- Content --> > </body> > > Now if the WebPage is the only entity is it then considered > to be the 'Subject', the 'Object' or both? > > 2] If the WebPage contains an entity, let's say a Product, > without specifying a property on the Product and I check > this with Google's SDTT, I see 2 'root' entities, since > there is no property to chain the two together. Yet I get > the impression the Product gets treated as the 'Object', > since it's the Product that gets used for Rich snippet > extraction, and that therefore the WebPage is the 'Subject' : > > code example: > <body itemscope itemtype="http://schema.org/WebPage"> > <span itemprop="name">Page title</span> > > <div itemscope itemtype="http://schema.org/Product"> > <span itemprop="name">Product name</span> > <!-- Product properties --> > </div> > </body> > > Now since "Every web page is implicitly assumed to be > declared to be of type WebPage" I was wondering if there > also is a property that is 'implicitly assumed to be > declared' (something like @contains) on the first entity > that comes after it, like Product in this case, which > indicates that the Product is the 'Object'? > > And if not, than how does a parser 'know' which of the > entities is the 'Subject' and which is the 'Object', > shouldn't there be a predicate for this? > > 3] When a WebPage contains a bunch of 'root' entities, how > does a parser make sense of this, does the DOM have anything > to do with this? > > <body itemscope itemtype="http://schema.org/WebPage"> > <span itemprop="name">Page title</span> > > <div itemscope itemtype="http://schema.org/Product"> > <span itemprop="name">Product 1 name</span> > <!-- Product properties --> > </div> > > <div itemscope itemtype="http://schema.org/Product"> > <span itemprop="name">Product 2 name</span> > <!-- Product properties --> > </div> > > <div itemscope itemtype="http://schema.org/LocalBusiness"> > <span itemprop="name">Business name</span> > <!-- Product properties --> > </div> > </body> > > Now the above could be full of misunderstandings because I > lack in theoretical knowledge still, but that's exactly the > thing I'm hoping to change. Who can enlighten me? > > > > > >
Received on Thursday, 17 April 2014 19:03:42 UTC