grok.Form subclasses expect an actions attribute when rendering

[Dan Fairs]

This is grok 0.12.1.

Forms created by subclassing grok.Form fail to render if no actions are specified. For example:

(app.py)
from zope.interface import Interface
from zope.schema import TextLine
import grok

class IDummyForm(Interface):
    name = TextLine(title=u'name')

class Content(grok.Application, grok.Container):
    grok.implements(IDummyForm)

class DummyForm(grok.Form):
    grok.context(Content)
    form_fields = [] # or grok.AutoFields(Content)

Visiting the /dummyform URL in the browser gives a traceback as follows:

2008-06-02T21:10:08 ERROR SiteError http://localhost:8080/foo/dummyform
Traceback (most recent call last):
  File "/Users/dan/.buildout/eggs/tmpHn7YIK/zope.publisher-3.5.0a1.dev_r78838-py2.5.egg/zope/publisher/publish.py", line 133, in publish
  File "/Users/dan/.buildout/eggs/tmp2mfFo8/grok-0.12.1-py2.5.egg/grok/publication.py", line 45, in callObject
  File "/Users/dan/.buildout/eggs/tmpjOPdnD/zope.app.publication-3.4.2-py2.5.egg/zope/app/publication/zopepublication.py", line 167, in callObject
  File "/Users/dan/.buildout/eggs/tmpHn7YIK/zope.publisher-3.5.0a1.dev_r78838-py2.5.egg/zope/publisher/publish.py", line 108, in mapply
   - __traceback_info__: <madhatter.app.DummyForm object at 0x1e8fb50>
  File "/Users/dan/.buildout/eggs/tmpHn7YIK/zope.publisher-3.5.0a1.dev_r78838-py2.5.egg/zope/publisher/publish.py", line 114, in debug_call
  File "/Users/dan/.buildout/eggs/tmp2mfFo8/grok-0.12.1-py2.5.egg/grok/components.py", line 500, in __call__
  File "/Users/dan/.buildout/eggs/tmp2mfFo8/grok-0.12.1-py2.5.egg/grok/components.py", line 472, in update_form
  File "/Users/dan/.buildout/eggs/tmpU7ZlvQ/zope.formlib-3.4.0-py2.5.egg/zope/formlib/form.py", line 740, in update
AttributeError: 'DummyForm' object has no attribute 'actions'

While forms with buttons are the common case, it's not hard to imagine a situation where a form might not have any buttons (perhaps the form is processed by some client-side javascript).

It should be possible to have forms without buttons (actions).

[Philipp von Weitershausen (philikon)]

On 2 Jun 2008, at 22:14 , Dan Fairs wrote:
> (app.py)
> from zope.interface import Interface
> from zope.schema import TextLine
> import grok
>
> class IDummyForm(Interface):
> name = TextLine(title=u'name')
>
> class Content(grok.Application, grok.Container):
> grok.implements(IDummyForm)
>
>
> class DummyForm(grok.Form):
> grok.context(Content)
> form_fields = [] # or grok.AutoFields(Content)
>
> Visiting the /dummyform URL in the browser gives a traceback as
> follows:
>
> 2008-06-02T21:10:08 ERROR SiteError http://localhost:8080/foo/
> dummyform
> Traceback (most recent call last):
> ...
> AttributeError: 'DummyForm' object has no attribute 'actions'
>
> While forms with buttons are the common case, it's not hard to
> imagine a
> situation where a form might not have any buttons (perhaps the form is
> processed by some client-side javascript).
>
> It should be possible to have forms without buttons (actions).

You can simply add the 'actions' attribute to the form class to avoid
the exception:

class DummyForm(grok.Form):
    ...
    actions = []

[Martijn Faassen (faassen)]

> You can simply add the 'actions' attribute to the form class to avoid
> the exception:
>
> class DummyForm(grok.Form):
> ...
> actions = []

This is a workaround though, not a solution. I think we should make
sure that if you don't use any @grok.action decorators, you still get
to see a form.

[Jan Wijbrand Kolman (janwijbrand)]

What about merely adding

  actions = form.Actions()

on the grokcore.formlib EditForm and AddForm baseclasses?

[Jan Wijbrand Kolman (janwijbrand)]

Fixed in grokcore.formlib trunk. We should remember to release a 1.0.1 of grokcore.formlib when releasing grok 1.0.