Indeed it's quite nice.
I've seen an issue if the underlying page is not big enough, the popup
won't overlap with the comments zone.
It could be nice if it could work with links from the document tree
Ludovic
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On Tue, Feb 19, 2019 at 2:01 PM Eduard Moraru <enygma2002(a)gmail.com> wrote:
  The result looks very nice!
 The loading time seems a bit long, probably because of the entire page
 rendering, but that should not be a big problem.
 Thanks,
 Eduard
 On Tue, Feb 19, 2019 at 9:52 AM Stéphane Laurière <slauriere(a)xwiki.com>
 wrote:
  Hi Eduard, Hi devs,
 I'm following up on this discussion which I had left aside for a while:
 Eduard Moraru:
 > Hi, Stephane.
 >
 > On Tue, Aug 28, 2018 at 10:49 AM Stéphane Laurière < 
slauriere(a)xwiki.com>
  > wrote:
 >
 >> Vincent Massol:
 >>> Hi Stephane,
 >>>
 >>>> On 28 Aug 2018, at 08:55, Stéphane Laurière <slauriere(a)xwiki.com>
 >> wrote:
 >>>>
 >>>> Hi all,
 >>>>
 >>>> I would like to contribute an extension that will display page 
preview
  >> popovers when hovering wiki links,
similarly to what MediaWiki offers:
 >>>>
 >>>>    
https://www.mediawiki.org/wiki/Page_Previews
 >>>> 
  >
 >
 > Sounds like a nice extension!
 >
 > However, how are you going to extract the "summary" of a page? In
 > Wikipedia, pages have a certain structure and, at the beginning of each
 > page, you have at least the first paragraph that is describing the
 > resource. Even the Wikipedia API allows you to get the "extract"
 > (summary/topic) of a page and that is what the Wikipedia feature is 
 using
   as text
content to display in that preview popup.
 In XWiki, the usecases are not defined and you could have anything 
 inside a
 > page. Do you plan to show the entire page content inside that preview? 
  Do
   you plan
to have an empirical approach in order to get some sort of 
 summary
 > by e.g. displaying just the first paragraph as well? What's the 
  approach?
 My proposal would be to make the approach configurable, so that the
 preview could be anything ranging from the full page to any element of 
 the
  page. The default configuration could consist in
displaying 1) the first
 block that matches one of the following: Paragraph, List, Quotation, 
 Table.
  2) the first image attached to the page, if any.
What do you think?
 In a second step, that could be nice to let the users define custom
 configurations to adapt the previews to their needs.
 >>
 >>>
 >>> Sounds nice. Do you plan to implement it as a Rendering 
Transformation
  >> (similar to what the Glossary app do) or
as Javascript code?
 >>
 >
 > Definitely  JavaScript + REST API would be the way to go here, to avoid
 > rendering, at display time, all the linked pages on the server side. 
 Each
   preview
should be obtained when the user asks for it, i.e. when 
 displaying
 > the preview. Optimisations could be done to prefetch the data, but that
 > would also increase the network traffic and server load, while 
  improving
   the user
experience (i.e. not having to wait for the preview popup to 
 load
  its content). 
 OK great, we agree on JavaScript then. I published a first experiment,
 welcoming code reviews and also feedback regarding the user experience:
    
https://github.com/xwiki-contrib/application-page-preview
 https://dev.xwiki.org/xwiki/bin/view/Drafts/Page%20Preview%20Application
 At the moment, the code is using a dedicated service rather than the REST
 API because it allows some flexibility such as the ability to display in
 the preview the first image attached to the target page even if it's not
 present in the content itself (this is probably something that should be
 made configurable).
 In a first try, I had extracted the preview on the server side using the
 XDOM API. However, following a discussion with Anca, I realised that it's
 probably more efficient to send the whole page rendered content and to 
  let
  the client display only part of it.
 >> Actually I had not considered the rendering transformation option. At
 >> first glance, plain JavaScript code seems more lightweight to me 
 without
  >> any downside but if you see pros for
using a transformation, please 
 let
  me
 >> know. There's one issue with plain JavaScript at the moment though: 
the
  >> Bootstrap popover feature in version 3.x
adds a div next to the 
 clicked
  >
element. In our case, this means adding a div to the surrounding
> span.wikilink, which is not allowed in HTML5. However, Bootstrap 4 
 popovers
 > work differently: they're added as direct
childs of the body:
> 
https://getbootstrap.com/docs/4.0/components/popovers/ so the issue 
 will
 >> be fixed once we migrate. What do you think? Can we live with a div 
  ina
  >> span for now?
 >>
 >
 > I'm not really sure what you mean. When the popover is displayed, a 
 divis
   indeed
created with javascript and added as sibling to the popover 
 trigger
 > element. If you make the "span" element the trigger instead of the 
 
link,
   then you
would get perfectly valid HTML. Example with Bootstrap 3:
 
http://jsfiddle.net/vqT5f/1322/ 
 You're right, I had certainly tried to add a popover the "a" element
 indeed, thank you for your help.
 Stéphane
 > Thanks,
 > Eduard
 >
 >
 >>
 >>>> Its name could be 'application-page-preview-popover' - what do
you
 >> think? As discussed with Caty yesterday, the extension will use the
 >> Bootstrap popovers. Should you have any need or suggestion, please 
  letme
  > know.
>>
>> So it depends on the technology you wish to use. If it’s a
> transformation, I would name it "transformation-preview”. If it’s
> JS/webjar, I guess you’ll need a JSX object to load it so I guess
> "application-page-preview” would be fine.
>
> I see, but in any case, with or without a transformation, I think we 
 will
 > need some JS + CSS code anyway, won't we?
As far as I can see, the 
 glossary
 >> extension is an application containing a transformation, so we could 
  go
  for
 > "application-page-preview" as well,
with or without transformation, 
 what do
 >> you think?
 >>
 >> Stéphane
 >>
 >>
 >>> Thanks
 >>> -Vincent
 >>>
 >>>> If the name is ok, can I ask you for the creation of a repository 
and
  > JIRA
project?
>>>
>>> Stéphane