menhir.contenttype.image 0.2

Dolmen content-type extension : image

menhir.contenttype.image provides an image-centered content type for Dolmen based Grok applications.

Schema

The menhir.contenttype.image Image content provides a custom schema, extending the IBaseContent interface, from dolmen.content:

>>> from dolmen.content import IBaseContent
>>> from menhir.contenttype.image import IImage

>>> IImage.isOrExtends(IBaseContent)
True

The IImage interface describes the image field, that is to store the uploaded image data. The field comes from dolmen.file:

>>> for attr, doc in IImage.namesAndDescriptions():
...   print attr, ':', doc
image : <dolmen.file.field.ImageField object at ...>

Factory

The menhir.contenttype.image Image content uses a ZODB Blob to store the data. The image attribute of the factory class, Image, is a blob property from dolmen.blob:

>>> from menhir.contenttype.image import Image
>>> Image.image
<dolmen.blob.property.BlobProperty object at ...>

The instanciation is fairly straightforward:

>>> import os.path
>>> path = os.path.join(os.path.dirname(__file__), 'image.png')

>>> imagefile = open(path)
>>> image = Image(title=u"My Image", image=imagefile)
>>> imagefile.close()

The factory is protected by a common dolmen.app.security right:

>>> from dolmen.content import require
>>> print require.bind().get(image)
dolmen.content.Add

Icon

The content registers an icon, thanks to the dolmen.app.content package:

>>> from zope.component import getMultiAdapter
>>> from zope.publisher.browser import TestRequest

>>> request = TestRequest()
>>> icon = getMultiAdapter((image, request), name="icon")
>>> print icon
<zope.browserresource.icon.IconView object at ...>

View

The content registers its own index view. It displays the image and a download link. To be able to display the content, we need it persisted in a locatable tree, as the links depend on the urls:

>>> from zope.component.hooks import getSite
>>> site = getSite()
>>> site['image'] = image

We can now summon the view and render it. The view is a dolmen.app.layout Page:

>>> from dolmen.app.layout import Page
>>> index = getMultiAdapter((image, request), name="index")
>>> isinstance(index, Page)
True

>>> index.update()
>>> print index.content()
<h1>My Image</h1>
<div class="content">
  <p class="download">
    <a href="http://127.0.0.1/image/++download++image"
       title="Download">Download</a>
    &mdash;
    <span>1 KB</span>
  </p>
  <div class="image">
    <a href="http://127.0.0.1/image/++thumbnail++image.large"
       class="image-link" title="My Image">
      <img src="http://127.0.0.1/image/++thumbnail++image.preview" />
    </a>
  </div>
</div>

Changelog

0.2 (2010-07-27)

• Packaging corrections.

0.1 (2010-07-21)

• Initial release