Package trac :: Package mimeview :: Module api :: Class Context

Class Context

object --+
         |
        Context

Rendering context.

A rendering context specifies ''how'' the content should be rendered. It holds together all the needed contextual information that will be needed by individual renderer components.

To that end, a context keeps track of the Href instance (.href) which should be used as a base for building URLs.

It also provides a PermissionCache (.perm) which can be used to restrict the output so that only the authorized information is shown.

A rendering context may also be associated to some Trac resource which will be used as the implicit reference when rendering relative links or for retrieving relative content and can be used to retrieve related metadata.

Contexts can be nested, and a new context can be created from an existing context using the call syntax. The previous context can be retrieved using the .parent attribute.

For example, when rendering a wiki text of a wiki page, the context will be associated to a resource identifying that wiki page.

If that wiki text contains a [[TicketQuery]] wiki macro, the macro will set up nested contexts for each matching ticket that will be used for rendering the ticket descriptions.

Since: version 0.11

Instance Methods

__init__(self, resource, href=None, perm=None)
Directly create a Context.

source code

__repr__(self)
repr(x)

source code

Context

__call__(self, resource=None, id=False, version=False, parent=False)
Create a nested rendering context.

source code

__contains__(self, resource)
Check whether a resource is in the rendering path.

source code

set_hints(self, **keyvalues)
Set rendering hints for this rendering context.

source code

get_hint(self, hint, default=None)
Retrieve a rendering hint from this context or an ancestor context.

source code

has_hint(self, hint)
Test whether a rendering hint is defined in this context or in some ancestor context.

source code

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __setattr__, __sizeof__, __str__, __subclasshook__

Class Methods

Context

from_request(cls, req, resource=None, id=False, version=False, parent=False, absurls=False)
Create a rendering context from a request.

source code

Instance Variables
	parent The parent context, if any

Properties
Inherited from `object`: `__class__`

Method Details

init(self, resource, href=None, perm=None)
(Constructor)

source code

Directly create a Context.

The actual .perm attribute of the rendering context will be bound to the given resource so that fine-grained permission checks will apply to that.

Parameters:

resource (Resource) - the associated resource
href - an Href object suitable for creating URLs
perm - a PermissionCache object used for restricting the generated output to "authorized" information only.

Overrides: object.__init__

from_request(cls, req, resource=None, id=False, version=False, parent=False, absurls=False)
Class Method

source code

Create a rendering context from a request.

The perm and href properties of the context will be initialized from the corresponding properties of the request object.

>>> from trac.test import Mock, MockPerm
>>> req = Mock(href=Mock(), perm=MockPerm())
>>> context = Context.from_request(req)
>>> context.href is req.href
True
>>> context.perm is req.perm
True

Parameters:

req - the HTTP request object
resource - the Resource object or realm
id - the resource identifier
version - the resource version
absurls - whether URLs generated by the href object should be absolute (including the protocol scheme and host name)

Returns: Context

a new rendering context

repr(self)
(Representation operator)

source code

repr(x)

Overrides: object.__repr__: (inherited documentation)

call(self, resource=None, id=False, version=False, parent=False)
(Call operator)

source code

Create a nested rendering context.

self will be the parent for the new nested context.

>>> context = Context('wiki', 'WikiStart')
>>> ticket1 = Resource('ticket', 1)
>>> context('ticket', 1).resource == ticket1
True
>>> context(ticket1).resource is ticket1
True
>>> context(ticket1)().resource is ticket1
True

Parameters:

resource - either a Resource object or the realm string for a resource specification to be associated to the new context. If None, the resource will be the same as the resource of the parent context.
id - the identifier part of the resource specification
version - the version of the resource specification

Returns: Context

the new context object

contains(self, resource)
(In operator)

source code

Check whether a resource is in the rendering path.

The primary use for this check is to avoid to render the content of a resource if we're already embedded in a context associated to that resource.

Parameters:

resource - a Resource specification which will be checked for

Class Context

__init__(self, resource, href=None, perm=None) (Constructor)

from_request(cls, req, resource=None, id=False, version=False, parent=False, absurls=False) Class Method

__repr__(self) (Representation operator)

__call__(self, resource=None, id=False, version=False, parent=False) (Call operator)

__contains__(self, resource) (In operator)

init(self, resource, href=None, perm=None)
(Constructor)

from_request(cls, req, resource=None, id=False, version=False, parent=False, absurls=False)
Class Method

repr(self)
(Representation operator)

call(self, resource=None, id=False, version=False, parent=False)
(Call operator)

contains(self, resource)
(In operator)