1 The VRegistry, selectors and application objects

     2 ================================================

     3 

     4 This chapter talks about core concepts of the |cubicweb| framework,

     5 that make it different from other frameworks (and maybe not easy to

     6 grasp at a first glance). To be able to do advanced development with

     7 |cubicweb| you need a good understanding of what is explained below.

     8 

     9 This chapter goes deep into details. You don't have to remember them

    10 all but keep it in mind so you can go back there later.

    11 

    12 An overview of AppObjects, the VRegistry and Selectors is given in the

    13 :ref:`VRegistryIntro` chapter.

    14 

    15 .. autodocstring:: cubicweb.cwvreg

    16 .. autodocstring:: cubicweb.selectors

    17 .. automodule:: cubicweb.appobject

    18 

    19 Base selectors

    20 --------------

    21 

    22 Selectors are scoring functions that are called by the registry to tell whenever

    23 an appobject can be selected in a given context. Selector sets are for instance

    24 the glue that tie views to the data model. Using them appropriately is an

    25 essential part of the construction of well behaved cubes.

    26 

    27 Of course you may have to write your own set of selectors as your needs grows and

    28 you get familiar with the framework (see :ref:`CustomSelectors`).

    29 

    30 Here is a description of generic selectors provided by CubicWeb that should suit

    31 most of your needs.

    32 

    33 Bare selectors

    34 ~~~~~~~~~~~~~~

    35 Those selectors are somewhat dumb, which doesn't mean they're not (very) useful.

    36 

    37 .. autoclass:: cubicweb.appobject.yes

    38 .. autoclass:: cubicweb.selectors.match_kwargs

    39 .. autoclass:: cubicweb.selectors.appobject_selectable

    40 

    41 

    42 Result set selectors

    43 ~~~~~~~~~~~~~~~~~~~~~

    44 Those selectors are looking for a result set in the context ('rset' argument or

    45 the input context) and match or not according to its shape. Some of these

    46 selectors have different behaviour if a particular cell of the result set is

    47 specified using 'row' and 'col' arguments of the input context or not.

    48 

    49 .. autoclass:: cubicweb.selectors.none_rset

    50 .. autoclass:: cubicweb.selectors.any_rset

    51 .. autoclass:: cubicweb.selectors.nonempty_rset

    52 .. autoclass:: cubicweb.selectors.empty_rset

    53 .. autoclass:: cubicweb.selectors.one_line_rset

    54 .. autoclass:: cubicweb.selectors.multi_lines_rset

    55 .. autoclass:: cubicweb.selectors.multi_columns_rset

    56 .. autoclass:: cubicweb.selectors.paginated_rset

    57 .. autoclass:: cubicweb.selectors.sorted_rset

    58 .. autoclass:: cubicweb.selectors.one_etype_rset

    59 .. autoclass:: cubicweb.selectors.multi_etypes_rset

    60 

    61 

    62 Entity selectors

    63 ~~~~~~~~~~~~~~~~

    64 Those selectors are looking for either an `entity` argument in the input context,

    65 or entity found in the result set ('rset' argument or the input context) and

    66 match or not according to entity's (instance or class) properties.

    67 

    68 .. autoclass:: cubicweb.selectors.non_final_entity

    69 .. autoclass:: cubicweb.selectors.implements

    70 .. autoclass:: cubicweb.selectors.score_entity

    71 .. autoclass:: cubicweb.selectors.rql_condition

    72 .. autoclass:: cubicweb.selectors.relation_possible

    73 .. autoclass:: cubicweb.selectors.partial_relation_possible

    74 .. autoclass:: cubicweb.selectors.has_related_entities

    75 .. autoclass:: cubicweb.selectors.partial_has_related_entities

    76 .. autoclass:: cubicweb.selectors.has_permission

    77 .. autoclass:: cubicweb.selectors.has_add_permission

    78 

    79 

    80 Logged user selectors

    81 ~~~~~~~~~~~~~~~~~~~~~

    82 Those selectors are looking for properties of the user issuing the request.

    83 

    84 .. autoclass:: cubicweb.selectors.anonymous_user

    85 .. autoclass:: cubicweb.selectors.authenticated_user

    86 .. autoclass:: cubicweb.selectors.match_user_groups

    87 

    88 

    89 Web request selectors

    90 ~~~~~~~~~~~~~~~~~~~~~

    91 Those selectors are looking for properties of *web* request, they can not be

    92 used on the data repository side.

    93 

    94 .. autoclass:: cubicweb.selectors.match_form_params

    95 .. autoclass:: cubicweb.selectors.match_search_state

    96 .. autoclass:: cubicweb.selectors.match_context_prop

    97 .. autoclass:: cubicweb.selectors.match_view

    98 .. autoclass:: cubicweb.selectors.primary_view

    99 .. autoclass:: cubicweb.selectors.specified_etype_implements

   100 

   101 

   102 Other selectors

   103 ~~~~~~~~~~~~~~~

   104 .. autoclass:: cubicweb.selectors.match_transition

   105 

   106 You'll also find some other (very) specific selectors hidden in other modules

   107 than :mod:`cubicweb.selectors`.