On Apr 16, 2012, at 10:23 PM, Jerome Velociter wrote: > On Mon, Apr 16, 2012 at 9:59 PM, Vincent Massol <[email protected]> wrote: >> Hi, >> >> On Apr 16, 2012, at 8:10 PM, Jean-Vincent Drean wrote: >> >>> Hi devs, >>> >>> while replacing calls to xwiki#searchDocuments by calls to the query >>> manager script service I ran into the following query manager issue: >>> http://jira.xwiki.org/browse/XWIKI-7273 (XWQL short form queries >>> should distinct on document fullname.) >>> >>> I think we could use the recent QueryFilter mechanism to handle the >>> addition of the "distinct" in the select statement. >>> https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwiki-platform-query/xwiki-platform-query-manager/src/main/java/org/xwiki/query/QueryFilter.java >>> >>> QueryFilters allow to: >>> - transform queries depending on a dynamic parameter (for example the >>> user preferences in HiddenDocumentFilter) >>> - transform the select part of a short query, without requiring >>> programming rights >>> >>> Here's an example of what it could look like from a velocity script: >>> ----------------------------------------------------8<---------------------------------------------------- >>> #set($query = >>> $services.query.xwql("").addFilter("unique").addFilter("hidden")) >>> ----------------------------------------------------8<---------------------------------------------------- >>> Note that in the future we could decide that the Query wrapper we use >>> in the QueryManagerScriptService (ScriptQuery) have the "unique" >>> filter by default + a way to remove it from the script. >>> >>> I wasn't expecting us to consider using multiple filters when I added >>> the new APIs in Query (4.0RC1). >>> If we agree that a QueryFilter would be a nice way to handle this, I'd >>> like to break those API before we release 4.0: >>> ----------------------------------------------------8<---------------------------------------------------- >>> - Query setFilter(QueryFilter filter); >>> + Query addFilter(QueryFilter filter); >>> - QueryFilter getFilter(); >>> + List<QueryFilter> getFilters(); >>> ----------------------------------------------------8<---------------------------------------------------- >> >> It's a little bit more complex. We did consider several filters when we >> added setFilter()!! :) >> >> We said that if we need more than one filter we could have an AndFilter() >> that takes a list of Filters. And allow more complex filters should we need >> them, like OrFilter, etc. >> >> #set($query = $services.query.xwql("").setFilter(new AndFilter("unique", >> "hidden")) >> >> Written with a fluent API that would give: >> >> #set($query = $services.query.xwql("").setFilter(and("unique", "hidden")) >> >> Or even: >> >> #set($query = $services.query.xwql("").setFilter("unique").and("hidden") >> >> Anyway I'm just mentioning this to explain what we thought about and an >> alternative to addFilter(). The only problem with addFilter() is if you need >> more complex Filters later on. It's not extensible whereas using AndFilter() >> and OrFilter() is more extensible at the expense of a little bit more text >> if not using a fluent api. > > Also you can't expose it that easily in velocity. For example your > fluent APIs examples above won't work in velocity ; you would need a > layer in between to adapt from script service APIs to the Java APIs.
You can't do a "new" but the point of the fluent API is to not have to write any "new" (to make it fluent) and thus it's well adapted to Velocity actually :) BTW on http://en.wikipedia.org/wiki/Fluent_interface#Java their examples shows a usage where they call setParameter several times. This is also a possibility. We can call setFilter() several times. Thanks -Vincent > Jerome. > >> >> Anyway I'm fine with either addFilter or setFilter. >> >> Also +1 to use a QueryFilter for adding a "distinct" in the query. >> >> Thanks >> -Vincent >> >>> WDYT ? >>> JV. _______________________________________________ devs mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/devs
