On Tue, Sep 23, 2014 at 4:44 PM, Garret Wilson <gar...@globalmentor.com>
wrote:

> OMG. What a sad email to wake up to. :(
>
> Let me let all that digest for a while. I never would have imagined a
> situation this dire. Imagine if every time you went to Facebook, it
> generated a new https://www.facebook.com/jdoe?124154451 version! So
> basically Facebook could never use Wicket without rewriting the whole page
> caching scheme. Or


this particular url (https://www.facebook.com/jdoe?124154451) returns 404,
but otherwise Facebook renders completely different content on page refresh
(and I'm OK with that!)


> LinkedIn. Or... actually, come to think of it, I can't even think of a
> single site that functions like Wicket, incrementing some "page version"
> counter every time you interact with the page, so that you can go back to
> other "versions". (Users don't want to go back to other versions! They may
> want to go back to other /pages/ at different URLs, but they realize that
> interacting with a single pages changes the state of that page---they don't
> expect that other "versions" are kept around somewhere.)
>

IPageSettings#setVersioned(false) disables the state management for all
pages in an application


>
> Continuing my scenario I outlined earlier, I have an HTML page called
> MenuPage, which has <wicket:link><a href="StagingPage.html">..., the target
> page of which functions as I explained below. Every time the user goes to
> the MenuPage and clicks on the link, you're saying that Wicket will
> generate a new version of StagingPage in the cache, even with
> setVersioned(false)? It will generate a new ...StagingPage.html?23423414
> URL? There is no way to turn that off... without essentially rewriting the
> whole Wicket page request and caching mechanism??
>

What is the actual problem ?
The number in the url ?
Or that a new page instance is created ?


>
> This is not good news. I'm not ranting, I'm crying.


Imagine this:
PageA initial state renders PanelA and a LinkA.
Clicking on LinkA PanelA is replaced with PanelB.

case 1) with the pageId in the url if you refresh the page then you will
still see PanelB in the page
case 2) without the pageId you will see PanelA, because a new page instance
is created

Now imagine that Wicket stores pages by type. Once the user clicks LinkA
how (s)he will be able to see the initial state with PanelA again ?



>
>
> Garret
>
>
> On 9/23/2014 8:24 AM, Martin Grigorov wrote:
>
>> Hi,
>>
>> In short, to accomplish all this you will need several custom impls of
>> Wicket interfaces.
>> 1) custom IRequestMapper that just ignores PageInfo when generating the
>> url
>> for IPageRequestHandler. Search in the archives for
>> "NoVersionRequestMapper"
>> 2) a completely new IPageManager (interface!) that works with Class<Page>
>> instead of with Integer (pageId)
>> So everytime a url is mapped to a page class you should use it to load the
>> Page instance for this class
>>
>> In details:
>> By design only stateless pages do not have the pageId in the url! If a
>> request without pageId comes then a completely new page instance is
>> created.
>> By using something like NoVersionRequestMapper (not supported officially!)
>> only the url for the browser address bar will miss the pageId (see
>> PageAndComponentInfo class), but the pageId is in all link/form urls so
>> clicking/submitting still works. But if the user refreshes the page (F5)
>> then the state is lost!
>>
>> About Page#setVersioned(boolean)
>> This tells Wicket to not increment the pageId after an interaction with
>> the
>> page. A pageId is associated with the page when it is instantiated, but
>> any
>> link click, form submit, etc. won't create a new version of the page. The
>> final result is that every interaction (i.e. state change) with the page
>> will lead to overriding the old one in the page stores.
>> Wicket's IPageStore/IDataStore use API like: put(String sessionId, int
>> pageId, byte[] serializedPage). At the end of every request cycle all
>> rendered stateful pages are stored. If the pageId doesn't change then some
>> old serializedPage would be overriden.
>>
>> For your requirements you will need an API like: put(String sessionId,
>> Class<Page> pageClass, byte[] serializedPage) and byte [] get(String
>> sessionId, Class<Page> pageClass).
>> You can create a IPageManager wrapper that maps sessionId+pageId to
>> pageClass and use that pageClass with custom IMyPageStore and IMyDataStore
>> impls. (Just an idea out of my mind.)
>>
>>
>> Martin Grigorov
>> Wicket Training and Consulting
>> https://twitter.com/mtgrigorov
>>
>> On Tue, Sep 23, 2014 at 3:42 AM, Garret Wilson <gar...@globalmentor.com>
>> wrote:
>>
>>  Can someone explain to me exactly how page versioning works, and how to
>>> turn it off?
>>>
>>> I have a page StagingPage that contains a file uploader. This page is
>>> interesting in that when you upload some files with Button1, the page
>>> lists
>>> the files on the page and keeps them in a collection until you hit
>>> Button2,
>>> at which point the pages does Some Other Really Interesting Thing with
>>> the
>>> files. In other words, the page acts like a staging area for files,
>>> allowing you to 1) upload files and then 2) do something with them.
>>>
>>> I get this number on the end of the URLs which, from the page versioning
>>> and caching reference documentation <http://wicket.apache.org/
>>> guide/guide/versioningCaching.html>, seems to indicate the version of
>>> the
>>> page. I don't want this. I just want there to be one version of the page
>>> (even though it is stateful). The back button can go to the previous
>>> page;
>>> I don't care.
>>>
>>> So I turn off versioning in StagingPage with:
>>>
>>>     setVersioned(false);
>>>
>>>
>>> But I still get numbers at the end of the StagingPage URL. Worse, back
>>> and
>>> forward in my browser goes between apparently two versions of the page
>>> (one
>>> with the "Choose Files" button selecting files, and one without)---but
>>> the
>>> number in the URL doesn't change! Worse still, when I remove the number
>>> and
>>> reload the URL without the number, Wicket puts the number back but first
>>> increments the number! Now back and forward cycle between numbered URLs.
>>>
>>> I thought setVersioned(false) was supposed to turn all that off?
>>>
>>> In my own Guise framework, each page has a single component instance tree
>>> on the back end. Whatever you do at that URL, whenever you come back to
>>> it
>>> it will be just like you left it. Granted, there are several drawbacks
>>> such
>>> as memory consumption; Guise can learn a lot from Wicket in how the
>>> latter
>>> can serialize each page between requests, and versioning can be very
>>> useful
>>> in some situations. But here I just want a stateful page that has one
>>> single version---the current version. I don't want it to remember any
>>> previous versions. And I don't want numbers on the end of the URL. How
>>> can
>>> I turn off versioning for real?
>>>
>>> Thanks,
>>>
>>> Garret
>>>
>>>
>

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