doc/book/devweb/searchbar.rst
author Philippe Pepiot <philippe.pepiot@logilab.fr>
Mon, 29 Oct 2018 10:04:31 +0100
changeset 12355 c703dc95c82e
parent 10491 c67bcee93248
permissions -rw-r--r--
Fix flake8 issues since release 3.6.0 Flake8 had a new release which raise new issues, namely: W504: line break after binary operator F841: local variable 'ex' is assigned to but never used W605: invalid escape sequence F821: undefined name 'buffer' (noqa seems the only way to avoid this false positive) Also pin flake8>=3.6 in our tests and make explicit that we use python3 to run flake8 tests.

.. _searchbar:

RQL search bar
--------------

The RQL search bar is a visual component, hidden by default, the tiny *search*
input being enough for common use cases.

An autocompletion helper is provided to help you type valid queries, both
in terms of syntax and in terms of schema validity.

.. autoclass:: cubicweb.web.views.magicsearch.RQLSuggestionsBuilder


How search is performed
+++++++++++++++++++++++

You can use the *rql search bar* to either type RQL queries, plain text queries
or standard shortcuts such as *<EntityType>* or *<EntityType> <attrname> <value>*.

Ultimately, all queries are translated to rql since it's the only
language understood on the server (data) side. To transform the user
query into RQL, CubicWeb uses the so-called *magicsearch component*,
defined in :mod:`cubicweb.web.views.magicsearch`, which in turn
delegates to a number of query preprocessor that are responsible of
interpreting the user query and generating corresponding RQL.

The code of the main processor loop is easy to understand:

.. sourcecode:: python

  for proc in self.processors:
      try:
          return proc.process_query(uquery, req)
      except (RQLSyntaxError, BadRQLQuery):
          pass

The idea is simple: for each query processor, try to translate the
query. If it fails, try with the next processor, if it succeeds,
we're done and the RQL query will be executed.