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 <slauri...@xwiki.com>
wrote:
Vincent Massol:
Hi Stephane,
On 28 Aug 2018, at 08:55, Stéphane Laurière <slauri...@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
https://blog.wikimedia.org/2018/05/09/page-previews-documentation/
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
