[server] extract "no pooler" CnxSet class to a _BaseCnxSet class
So we get rid of "if self._queue is None" in each method of _CnxSetPool
Also add helper get_cnxset(source, size) to instantiate the correct pooler class.
.. winclude:: search_sample_queries
You can as well type complex queries using the RQL_ query language,
used every where to build dynamic pages of this site.
You can use one of the following prefixes to specify which kind of search you
want:
* `rql` : RQL query
* `text` : full text search
.. _RQL: tut_rql