Edgewall Software

Changes between Version 2 and Version 3 of TracDev/Proposals/ControllerApi


Ignore:
Timestamp:
Jun 22, 2006, 7:52:25 PM (13 years ago)
Author:
Christopher Lenz
Comment:

Note about decorator usage

Legend:

Unmodified
Added
Removed
Modified
  • TracDev/Proposals/ControllerApi

    v2 v3  
    44== Status Quo ==
    55
    6 The current web layer in Trac is quite low-level. It builds directly on the component architecture, and requires a “controller” to implement the `IRequestHandler` interface and expose two methods: `match_request(req)` and `process_request(req)`. The former method is called by the request dispatcher to determine which controller should handle a particular request. The latter is then called on the controller that was chosen.
     6The current web layer in Trac is quite low-level. It builds directly on the component architecture, and requires a “controller” to implement the `IRequestHandler` interface and expose two methods: `match_request(req)` and `process_request(req)`. The former method is called by the request dispatcher to determine which controller should handle a particular request. The latter is then called on the controller that was chosen.
    77
    88The following example defines a (heavily simplified) controller based on that API:
     
    7070== Proposal: Controller Class ==
    7171
    72 This proposal extracts these common patterns from the individual controllers, and introduces a base class called `Controller` that allows for more convenient handling of requests. That class extends `Component` and implements the `IRequestHandler` interface, so that a concrete controller can still directly extend other extension points, such as `INavigationContributor`.
     72This proposal extracts these common patterns from the individual controllers, and introduces a base class called `Controller` that allows for more convenient handling of requests. That class extends `Component` and implements the `IRequestHandler` interface, so that a concrete controller can still directly extend other extension points, such as `INavigationContributor`.
    7373
    7474When a controller is derived from the {{{Controller}}} base class, it should not need to implement `match_request()` or `process_request()`. Instead:
     
    104104In addition, request parameters that the controller method declares as keyword arguments are automatically extracted from the request and passed as parameters (although always as string, so that sometimes the parameter value will still need to be casted).
    105105
    106 One difference to the current code in Trac is that both `GET` and `POST` requests are handled by the same method. This will make it easier to implement user-friendly validation where a `POST` request with validity errors results in the form being redisplayed.
     106One difference to the current code in Trac is that both `GET` and `POST` requests are handled by the same method. This will make it easier to implement user-friendly validation where a `POST` request with validity errors results in the form being redisplayed.
    107107
    108108=== Conventions and Convenience Features ===
     
    139139The code can be checked out from the [source:sandbox/controller] branch of the SubversionRepository.
    140140
     141Note that the branch currently requires Python 2.4 due to the use of decorators, but will be backported to 2.3 before/if it gets merged.
     142
    141143----
    142144See also: [wiki:TracDev/Proposals], TracDev