Hi MS>> The ClientSideWindowHandler solution in CODI looks good so far, but there MS>> is still a lot to do.
MS>> And like every technology, it has it's pros and cons... MS>> What do you think about making the windowId provider pluggable in MyFaces MS>> core first? I have been thinking about every possible option we have for implement this and the conclusion was the best way is make something like the hack done in CODI or a "variant" of it, like the one described on: http://wiki.apache.org/myfaces/Drafts/WindowId (Mixed approach of the first prototype) >From the point of view of MyFaces Core, any solution should be bound to the renderkit in some way. So, windowId concept has sense to include it on the spec but its implementation should be done according to the renderkit. If the renderkit handles html, do the hack proposed but if is xml, do other thing and so on. It sounds like something to do outside MyFaces Core. Basically the problem is how to create an interface about something that could require changes over the renderkit/viewhandler?. Maybe we can minimize the problem, and provide an interface like this: public interface WindowIdRenderKitAware { public String getCurrentWindowId(FacesContext facesContext); } But let the details about how to "plug" all pieces inside CODI. MyFaces Core just offer the "integration point", and the default algorithm just do what is doing right now. Who should implement this interface? the renderkit, even if in the implementation the value can be stored inside FacesContext attribute map or request map. There exists a RenderKitWrapper interface, so it is easy to create a wrapper for default HTML_BASIC renderkit or any other and then scan through the wrappers and the first one implementing the interface will be the choosen. MS>> The REAL problem with JSF and multiple tabs is that once you open 2 tabs MS>> and click in 1 of them often enough, then you will destroy the state of MS>> the view in the other tab as well somewhen. Usually after 20 requests MS>> (default). There are two points where this logic could be useful inside MyFaces Core : 1. Server side state 2. Flash scope But in practice the only really relevant is 1. To implement 2. it is necessary a "requestId". MyFaces FlashImpl uses a counter and store its value inside a cookie. To fix this scope properly, the best is create a ExternalContext wrapper and provide and alternate Flash object, but that sounds like something that can be done outside MyFaces Core. If you are using CDI scopes, it sounds reasonable to provide an alternate Flash scope in CODI. If we can just modify the logic inside server side state to include "windowId" concept, it will be enough. MS>> To come over this, we need to store the n last views not only per session, MS>> but also per browser tab (==windowId). MS>> Of course, there can be lots of fancy stuff done to detect closed tabs, MS>> etc. But all this is much more stable if we really have the opportunity MS>> to distinguish between tabs. We can e.g. also introduce a configuration MS>> for maximum allowed tabs, to reduce memory blasting. Really since all state is stored in session, if the session is invalidated all tabs are removed from memory. Basically we already have params for max number of sessions and max number of logical sessions (which in fact can be seen as "tabs"). So what we have right now is ok, we just need to include windowId concept into the logic and that's it. MS>> All this is actually completely independent of how the windowId get's MS>> created and checked imo. Yes, that's right. MS>> I now tend to do the following (just atm creating a better playground MS>> example in CODI + hack on the ClientSideWindowHandler): MS>> MS>> a.) the cookie thingy is pretty bääh. it just doesn't work if a user clicks MS>> quickly through a list and opens lots of 'detail pages' on different tabs MS>> within 2 seconds. MS>> MS>> b.) it's currently a 'one or the other' thingy, and I now thought about MS>> combining the lazyWindowIdDropp.js and the current windowhandler.js MS>> MS>> My current research goes into the direction of MS>> MS>> 1.) always adding the windowId to each and every link and transport the MS>> windowId only via this parameter. MS>> MS>> 2.) For HTML5-browsers (detected via UserAgent) I render the MS>> windowhandler.html intermediate page which does all the fancy stuff of MS>> dynamically applying the old DOM on the intermediate page, etc. For other MS>> clients we rely on the lazyWindowId script. Ok, sounds promising. So, I'll focus on how to fix the logic for myfaces core server side state saving (org.apache.myfaces.renderkit.ServerSideStateCacheImpl), with the alternative proposed in this mail (WindowIdRenderKitAware interface, and then use a RenderKit wrapper). regards, Leonardo Uribe 2011/11/18 Mark Struberg <[email protected]>: > I now tend to do the following (just atm creating a better playground example > in CODI + hack on the ClientSideWindowHandler): > > a.) the cookie thingy is pretty bääh. it just doesn't work if a user clicks > quickly through a list and opens lots of 'detail pages' on different tabs > within 2 seconds. > > b.) it's currently a 'one or the other' thingy, and I now thought about > combining the lazyWindowIdDropp.js and the current windowhandler.js > > My current research goes into the direction of > > 1.) always adding the windowId to each and every link and transport the > windowId only via this parameter. > > 2.) For HTML5-browsers (detected via UserAgent) I render the > windowhandler.html intermediate page which does all the fancy stuff of > dynamically applying the old DOM on the intermediate page, etc. For other > clients we rely on the lazyWindowId script. > > Any help is welcome. > > > LieGrue, > strub > > > > ----- Original Message ----- >> From: Jakob Korherr <[email protected]> >> To: MyFaces Development <[email protected]>; Mark Struberg >> <[email protected]> >> Cc: >> Sent: Friday, November 18, 2011 2:23 PM >> Subject: Re: [core extcdi] is required to create another proposal about >> windowId? >> >> Hi, >> >>> PS: btw, a PhD student in my institute made me aware of a trick with the >> browser history. I think Jakob also already researched in this direction: >>> https://github.com/balupton/history.js/wiki/Intelligent-State-Handling >>> This mechanism does only 1 GET request (mine does 2), but with pure AJAX >> you imo cannot fully replace the header once the window is fully loaded. Thus >> you cannot easily handle dynamically loaded CSS, background images, etc with >> this approach. >> >> Yeap, I did some research in this area and also came across >> https://github.com/balupton/history.js (there are actually a hand full >> of projects on github which accomplish the same thing). This sure is a >> very good way of implementing a rich web 2.0 application with working >> history (--> back button), facebook and twitter are surely the most >> famous examples of this technique. >> >> However, Mark is right: doing this, you will end up in a lot of >> browser related problems when it comes to dynamic loading of >> stylesheets, scripts, etc.. Facebook and twitter managed to get this >> working for their purposes, but IMO it is not that easy for a standard >> JSF developer/architect. >> >> Regards, >> Jakob >> >> 2011/11/18 Mark Struberg <[email protected]>: >>> Hi! >>> >>> The ClientSideWindowHandler solution in CODI looks good so far, but there >> is still a lot to do. >>> >>> And like every technology, it has it's pros and cons... >>> >>> What do you think about making the windowId provider pluggable in MyFaces >> core first? >>> >>> The REAL problem with JSF and multiple tabs is that once you open 2 tabs >> and click in 1 of them often enough, then you will destroy the state of the >> view >> in the other tab as well somewhen. Usually after 20 requests (default). >>> >>> To come over this, we need to store the n last views not only per session, >> but also per browser tab (==windowId). >>> Of course, there can be lots of fancy stuff done to detect closed tabs, >> etc. But all this is much more stable if we really have the opportunity to >> distinguish between tabs. We can e.g. also introduce a configuration for >> maximum >> allowed tabs, to reduce memory blasting. >>> >>> All this is actually completely independent of how the windowId get's >> created and checked imo. >>> >>> >>> LieGrue, >>> strub >>> >>> PS: btw, a PhD student in my institute made me aware of a trick with the >> browser history. I think Jakob also already researched in this direction: >>> https://github.com/balupton/history.js/wiki/Intelligent-State-Handling >>> This mechanism does only 1 GET request (mine does 2), but with pure AJAX >> you imo cannot fully replace the header once the window is fully loaded. Thus >> you cannot easily handle dynamically loaded CSS, background images, etc with >> this approach. >>> >>> >>> >>> ----- Original Message ----- >>>> From: Leonardo Uribe <[email protected]> >>>> To: MyFaces Development <[email protected]> >>>> Cc: >>>> Sent: Thursday, November 17, 2011 9:39 PM >>>> Subject: Re: [core extcdi] is required to create another proposal about >> windowId? >>>> >>>> Hi Gerhard >>>> >>>> Ok, good to know that. I'll work on a solution based on the >> previous >>>> discussions about it to have more options in this case. >>>> >>>> regards, >>>> >>>> Leonardo Uribe >>>> >>>> 2011/11/17 Gerhard Petracek <[email protected]>: >>>>> hi leo, >>>>> >>>>> as soon as the new approach works, we can suggest it for jsf 2.2. >>>>> however, since it's only compatible with html5, we have to >> suggest a >>>>> 2nd approach (e.g. the default behaviour of codi). >>>>> >>>>> regards, >>>>> gerhard >>>>> >>>>> http://www.irian.at >>>>> >>>>> Your JSF powerhouse - >>>>> JSF Consulting, Development and >>>>> Courses in English and German >>>>> >>>>> Professional Support for Apache MyFaces >>>>> >>>>> >>>>> >>>>> 2011/11/17 Werner Punz <[email protected]>: >>>>>> Am 11/17/11 7:15 PM, schrieb Leonardo Uribe: >>>>>>> >>>>>>> Hi >>>>>>> >>>>>>> In the last days there was some work in these issues: >>>>>>> >>>>>>> (EXTCDI-242) improve ClientSideWindowHandler windowId >> passing via >>>> cookie >>>>>>> (EXTCDI-241) Allow users of the ClientSideWindowHandler to >> specify >>>> if >>>>>>> it should get applied per Request >>>>>>> (EXTCDI-240) Enhance ClientSideWindowHandler - remove >> flickering, >>>> etc >>>>>>> >>>>>>> Just one question: if the flickering problem was fixed on >> the >>>> current >>>>>>> solution done on EXTCDI, it is still necessary to create >> an >>>>>>> implementation inside myfaces core for windowId? This >> problem is on >>>> my >>>>>>> list of things to do, so it is better to ask first. >>>>>>> >>>>>>> regards, >>>>>>> >>>>>>> Leonardo Uribe >>>>>>> >>>>>> Good question, I guess we need something for WindowID handling >> for >>>> jsf2.2 >>>>>> especially given in hindisght of what is planned for 2.2 >> according to >>>> Ed >>>>>> Burns blog but the final answer for now is up to the CODI >> guys. >>>>>> >>>>>> Werner >>>>>> >>>>>> >>>>>> >>>>> >>>> >>> >> >> >> >> -- >> Jakob Korherr >> >> blog: http://www.jakobk.com >> twitter: http://twitter.com/jakobkorherr >> work: http://www.irian.at >> >
