Re: [xwiki-devs] Creation of transformation

On 25 Oct 2017, at 09:16, Sarthak Gupta <sarthakgupta072(a)gmail.com>

On Tue, Oct 24, 2017 at 9:34 PM, Vincent Massol <vincent(a)massol.net>

> Hi Sarthak, > >> On 24 Oct 2017, at 17:30, Sarthak Gupta &lt;sarthakgupta072(a)gmail.com&gt; > wrote: >> >> Hello Vincent, >> I have some confusion regarding transformations. >> >> https://github.com/xwiki-contrib/application-glossary/ > blob/master/application-glossary-api/src/main/java/ > org/xwiki/contrib/glossary/internal/GlossaryTransformation.java >> >> In my transformations, I am basically executing a query, which will get > the >> document names(say 'name') of glossary items from the glossary space >> . And the simply passing a string reference called 'Glossary.name' as a >> parameter to the DocumentResourceReference just like WikiWord >> Transformation. So, I think it should create links to the respective >> glossary pages. >> >> But as you commented on my recent commit >> <https://github.com/xwiki-contrib/application-glossary/commit/ > 9b04543627c7ccec0461a5d39d2b3f53f0d2815c#comments> >> that >> the method instead of returning the "names", it should load the

>> data from the xobjects. I suppose this will function like: when a user > will >> move their cursor on a particular glossary item present on a particular >> page, then it will load the information on the spot. Am I right? I

>> know but I think that I am not getting it right? > > When a page is rendered, it’s first parsed into a XDOM object and then

> active transformations are executed one after another. Active > Transformations are controlled by the rendering.transformations

​Hello Vincent, ​ > The GlossaryTransformation should traverse the whole tree of Blocks

> the XDOM and try to find set of words that match the entries contained

> Glossary xobjects. > > So in the 1st version, all you need to do is at the beginning of

> you run a query to get the full list of glossary xobjects and extract

​I think I am doing the same thing.​ You should ofc never run a query on each Block! That would kill the wiki

transform() block and storing the names in a list. And for each Block, I

just fetching the names from the list. Ok. wait! I should try executing this tranformation locally on my xwiki instance first and make changes accordingly.

For running the transformation, I am placing the jar file generated in application-glossary/application-glossary-api/target in usr/lib/xwiki/WEB-INF/lib/ (and) importing the xar file in application-glossary-api/target. Is this right?​

Thanks ​-Sarthak Gupta​ ​ > There’s nothing more, it’s very very simple. > > The harder part comes in the second version of the code when you improve > the performance so that the query is only executed when a Glossary

> is added/modified/deleted. You’ll implement that by using an

> to refresh the cached list of Glossary names. > > Is that clear? :) I thought I had explained this already several times

> maybe I’m not clear but I don’t know how to make it more clear. So you

> to tell me if there’s something not clear and what. > >> Thanks. >> -Sarthak Gupta >> >> P.S Sorry for my previous commits, Instead of 'git pull -f' I did

>> 'git pull' so changes got merged. :P > > ok!! You should always check the diff (git show -p <sha1>) before

> changes to avoid pushing wrong or unfinished things :) > > Thanks > -Vincent > >> On Tue, Oct 17, 2017 at 7:31 PM, Vincent Massol &lt;vincent(a)massol.net&gt; > wrote: >> >>> Hi Sarthak, >>> >>>> On 15 Oct 2017, at 21:43, Sarthak Gupta &lt;sarthakgupta072(a)gmail.com&gt; >>> wrote: >>>> >>>> >>>> >>>> On Sun, Oct 15, 2017 at 7:53 PM, Vincent Massol &lt;vincent(a)xwiki.com&gt; >>> wrote: >>>> Hi Sarthak, >>>> >>>>> On 14 Oct 2017, at 09:52, Sarthak Gupta &lt;sarthakgupta072(a)gmail.com&gt; >>> wrote: >>>>> >>>>> Hello, >>>>> As the tests of my project application-glossary >>>>> <https://github.com/xwiki-contrib/application-glossary> are not >>> working >>>> >>>> I’ll try to have a look when I’m back from GSOC summit. >>>> >>>>> , in >>>>> spite of my attempts(I will handle then later), I am moving on to >>>>> implementing the next feature of the application i.e creating >>>>> transformation. >>>>> As far as I understand, the transformation requires a cache

>>> from >>>>> which entries shall be taken for rendering purpose. This cache

>>> get >>>>> updated when a glossary xobject is added, deleted or modified. For > this >>>>> functionality to take place, it should make use of an Event

>>>>> >>>>> Hope I am right till now? >>>> >>>> Yes that’s exactly it! >>>> >>>> >>>> ​Hello Vincent, >>>> ​ >>>> What I would suggest is that you implement the Transformation without >>> cache for the first version, you make the app work fully end to end,

>>> release a 1.0 version that the community can try out, and then you

>>> working on version 1.1 which adds the cache to improve performance. >>>> >>>> WDYT? >>>> >>>> ​I think for implementing the transformations, some source will be >>> required from which the entries already present in the Glossary space > will >>> be taken. Here it is the cache object. So, an alternative here can be

>>> ​use the "query module" everytime for knowing which entries are

> in >>> the Glossary Space. And that would slow down the Xwiki to a large > extent I >>> guess because for each word a query will be executed. Would using the >>> "Query" be fine or there can be any other better approach? >>> >>> Some ideas: >>> >>> Version 1.0: >>> * When the transformation executes (i.e. when a page is rendered), you > do >>> a query to get the glossary entries. >>> >>> Version 1.1: >>> * You make your transformation implement Initializable and in > initialize() >>> you go a query to get all existing Glossary entries that you save in a >>> cache component that you write >>> * The cache component internally uses a Cache<> object for storing the >>> Glossary entries >>> * You also implement a component implementing EventListener that gets > the >>> cache component injected so that you can update the cache when

>>> xobjects are created/modified/deleted. >>> >>> If you feel comfortable you can implement directly version 1.1 but my >>> recommendation would be get a working v1.0 version ASAP and then > iterate to >>> improve it. >>> >>> Hope it helps, >>> Thanks >>> -Vincent >>> >>> PS: Please keep the discussion on the list so that anyone can help you > and >>> see the answers and chime in or just learn from it! :) >>> >>>> Thanks >>>> >>>> Sarthak Gupta >>>> >>>> >>>>> >>>>> I have a question in my mind. >>>>> >>>>> The "cache" and the "event Listener" are to be implemented as two >>> separate >>>>> components. right? >>>> >>>> Correct. >>>> >>>>> What I think is, that the EventListener component should be filled > with >>>>> appropriate methods just like this >>>>> <https://github.com/xwiki/xwiki-platform/blob/master/ >>> xwiki-platform-core/xwiki-platform-component/xwiki- >>> platform-component-wiki/src/main/java/org/xwiki/component/ >>> wiki/internal/bridge/DefaultWikiObjectComponentMana > gerEventListener.java> >>>>> and >>>>> then in these methods, the cache should be updated. >>>>> >>>>> Is this implementation right? >>>> >>>> Correct. >>>> >>>>> And after this, the rendering part will come…. >>>> >>>> Awesome. >>>> >>>> Thanks. Let me know if you need more of my/our help. >>>> -Vincent >>>> >>>>> >>>>> Thanks >>>>> >>>>> Sarthak Gupta