--- a/doc/book/en/development/devweb/controllers.rst Fri Apr 23 17:07:55 2010 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,199 +0,0 @@
-.. _controllers:
-
-Controllers
------------
-
-Overview
-++++++++
-
-Controllers are responsible for taking action upon user requests
-(loosely following the terminology of the MVC meta pattern).
-
-The following controllers are provided out-of-the box in CubicWeb. We
-list them by category.
-
-`Browsing`:
-
-* the View controller (web/views/basecontrollers.py) is associated
- with most browsing actions within a CubicWeb application: it always
- instantiates a `main template` and lets the ResultSet/Views dispatch
- system build up the whole content; it handles ObjectNotFound and
- NoSelectableObject errors that may bubble up to its entry point, in
- an end-user-friendly way (but other programming errors will slip
- through)
-
-* the JSon controller (web/views/basecontrollers.py) provides services
- for Ajax calls, typically using JSON as a serialization format for
- input, and sometimes using either JSON or XML for output;
-
-* the Login/Logout controllers (web/views/basecontrollers.py) make
- effective user login or logout requests
-
-`Edition`:
-
-* the Edit controller (see :ref:`edit_controller`) handles CRUD
- operations in response to a form being submitted; it works in close
- association with the Forms, to which it delegates some of the work
-
-* the Form validator controller (web/views/basecontrollers.py)
- provides form validation from Ajax context, using the Edit
- controller, to implement the classic form handling loop (user edits,
- hits 'submit/apply', validation occurs server-side by way of the
- Form validator controller, and the UI is decorated with failure
- information, either global or per-field , until it is valid)
-
-`Other`:
-
-* the SendMail controller (web/views/basecontrollers.py) is reponsible
- for outgoing email notifications
-
-* the MailBugReport controller (web/views/basecontrollers.py) allows
- to quickly have a `repotbug` feature in one's application
-
-Registration
-++++++++++++
-
-All controllers (should) live in the 'controllers' namespace within
-the global registry.
-
-API
-+++
-
-Most API details should be resolved by source code inspection, as the
-various controllers have differing goals.
-
-`web/controller.py` contains the top-level abstract Controller class and
-its (NotImplemented) entry point `publish(rset=None)` method.
-
-A handful of helpers are also provided there:
-
-* process_rql builds a result set from an rql query typically issued
- from the browser (and available through _cw.form['rql'])
-
-* validate_cache will force cache validation handling with respect to
- the HTTP Cache directives (that were typically originally issued
- from a previous server -> client response); concrete Controller
- implementations dealing with HTTP (thus, for instance, not the
- SendMail controller) may very well call this in their publication
- process.
-
-
-.. _edit_controller:
-
-The `edit controller`
-+++++++++++++++++++++
-
-It can be found in (:mod:`cubicweb.web.views.editcontroller`).
-
-Editing control
-~~~~~~~~~~~~~~~~
-
-Re-requisites: the parameters related to entities to edit are
-specified as follows ::
-
- <field name>:<entity eid>
-
-where entity eid could be a letter in case of an entity to create. We
-name those parameters as *qualified*.
-
-1. Retrieval of entities to edit by looking for the forms parameters
- starting by `eid:` and also having a parameter `__type` associated
- (also *qualified* by eid)
-
-2. For all the attributes and the relations of an entity to edit:
-
- 1. search for a parameter `edits-<relation name>` or `edito-<relation name>`
- qualified in the case of a relation where the entity is object
- 2. if found, the value returned is considered as the initial value
- for this relaiton and we then look for the new value(s) in the parameter
- <relation name> (qualified)
- 3. if the value returned is different from the initial value, an database update
- request is done
-
-3. For each entity to edit:
-
- 1. if a qualified parameter `__linkto` is specified, its value has to be
- a string (or a list of string) such as: ::
-
- <relation type>:<eids>:<target>
-
- where <target> is either `subject` or `object` and each eid could be
- separated from the others by a `_`. Target specifies if the *edited entity*
- is subject or object of the relation and each relation specified will
- be inserted.
-
- 2. if a qualified parameter `__clone_eid` is specified for an entity, the
- relations of the specified entity passed as value of this parameter are
- copied on the edited entity.
-
- 3. if a qualified parameter `__delete` is specified, its value must be
- a string or a list of string such as follows: ::
-
- <ssubjects eids>:<relation type>:<objects eids>
-
- where each eid subject or object can be seperated from the other
- by `_`. Each relation specified will be deleted.
-
- 4. if a qualified parameter `__insert` is specified, its value should
- follow the same pattern as `__delete`, but each relation specified is
- inserted.
-
-4. If the parameters `__insert` and/or `__delete` are found not qualified,
- they are interpreted as explained above (independantly from the number
- of entities edited).
-
-5. If no entity is edited but the form contains the parameters `__linkto`
- and `eid`, this one is interpreted by using the value specified for `eid`
- to designate the entity on which to add the relations.
-
-
-.. note::
-
- * If the parameter `__action_delete` is found, all the entities specified
- as to be edited will be deleted.
-
- * If the parameter `__action_cancel` is found, no action is completed.
-
- * If the parameter `__action_apply` is found, the editing is
- applied normally but the redirection is done on the form (see
- :ref:`RedirectionControl`).
-
- * The parameter `__method` is also supported as for the main template
-
- * If no entity is found to be edited and if there is no parameter
- `__action_delete`, `__action_cancel`, `__linkto`, `__delete` or
- `__insert`, an error is raised.
-
- * Using the parameter `__message` in the form will allow to use its value
- as a message to provide the user once the editing is completed.
-
-
-.. _RedirectionControl:
-
-Redirection control
-~~~~~~~~~~~~~~~~~~~
-Once editing is completed, there is still an issue left: where should we go
-now? If nothing is specified, the controller will do his job but it does not
-mean we will be happy with the result. We can control that by using the
-following parameters:
-
-* `__redirectpath`: path of the URL (relative to the root URL of the site,
- no form parameters
-
-* `__redirectparams`: forms parameters to add to the path
-
-* `__redirectrql`: redirection RQL request
-
-* `__redirectvid`: redirection view identifier
-
-* `__errorurl`: initial form URL, used for redirecting in case a validation
- error is raised during editing. If this one is not specified, an error page
- is displayed instead of going back to the form (which is, if necessary,
- responsible for displaying the errors)
-
-* `__form_id`: initial view form identifier, used if `__action_apply` is
- found
-
-In general we use either `__redirectpath` and `__redirectparams` or
-`__redirectrql` and `__redirectvid`.
-