zeam.utils.batch 1.1

Generic Batch support for Zope

Example

A very straightforward example. We need to define a context to work on:

>>> import grokcore.view as grok
>>> from persistent import Persistent
>>> from zope.component import queryMultiAdapter
>>> from zeam.utils.batch import Batch
>>> from zeam.utils.batch.interfaces import IBatching

>>> class Content(Persistent):
...     pass

And now, you can define a view which use a batch, and render it:

>>> class MyViewClass(grok.View):
...     grok.context(Content)
...
...     def update(self):
...          fulllist = [1, 2, 3, 4, 5, 6, 7, 8, 9]
...          self.myitems = Batch(
...                 fulllist , count=3, name='nbs', request=self.request,
...                 factory=lambda x: str(x))
...
...          self.batch = queryMultiAdapter(
...                 (self, self.myitems, self.request),
...                     IBatching)()
...
...     template = grok.PageTemplate('''
...     <tal:navigation tal:replace="structure view/batch" />
...     <span tal:content="item" tal:repeat="item view/myitems" />
...     <tal:navigation tal:replace="structure view/batch" />
...     ''')

And this work:

>>> from grokcore.component import testing
>>> testing.grok_component("view", MyViewClass)
True

>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()

>>> root = getRootFolder()
>>> root['myObject'] = Content()
>>> myobj = root['myObject']

>>> view = queryMultiAdapter((myobj, request), name="myviewclass")
>>> "batchNav" in view()
True

API

Batch

This object implements the batch.

The batch object is instanciated with the following arguments:

• a list of the objects to batch
• the request
• the number of items per page (as count, default to 10)
• a name (optional)
• a factory that will be passed each item before each iteration (optional)

The batch is an iterable object behaving like a list. It only gives access to the set of objects for the current page.

It provides the number of pages generated and the current position. Please refer to the interface, for more information.

A multi adapter providing IBatching can render the batch. It adapts the context, the batch object and the request. The __call__ method of this component will return a snippet of HTML containing basic controls for your batch: a next and previous link and a direct access to the other pages.

DateBatch

This object implements a batch for date range. It follows the same API than the regular batch, except:

• the list of objects is replaced by a callable that takes a datetime value has parameter and return a list of objects for the given periode
• the count option is changed to use either the BATCH_DAY or BATCH_MONTH marker object.

Changelog