如何在不使用文件的情况下以编程方式将模板文本传递给视图？

Question

我正在编写一些测试，我需要在我的视图中使用模板，而不需要使用文件(例如通过ViewPageTemplateFile)。模板必须计算tal表达式并访问视图的函数。这是我目前的问题。我在计算view时遇到了一个PageTemplate错误。我不确定我的代码是否遵循最佳实践。

from plone.app.testing import TEST_USER_NAME, TEST_USER_PASSWORD
from plone.testing.z2 import Browser
from zope.component import getGlobalSiteManager
from zope.publisher.interfaces.browser import IBrowserView
from Products.Five.browser import BrowserView
from zope.pagetemplate.pagetemplate import PageTemplate

class MyView(BrowserView):
    def __init__(self, context, request):
        self.context = context
        self.request = request
    def render(self):
        template = PageTemplate()
        text = '''\
<div tal:on-error="string:view fails"><span tal:replace="view/var"/></div>
<div tal:on-error="string:python fails"><span tal:replace="python:'python works'"/></div>
            '''
        template.write(text)
        return template()
    def __call__(self):
        return self.render()
    def var(self):
        return 'my_value'

global_site_manager = getGlobalSiteManager()
global_site_manager.registerAdapter(MyView, (None, None), IBrowserView, 'my_view')

browser=Browser(app.Plone)
browser.addHeader('Authorization',
                  'Basic %s:%s' % (TEST_USER_NAME, TEST_USER_PASSWORD))
browser.open(app.Plone.absolute_url() + '/@@my_view')
print browser.contents

产生下列产出：

<div>view fails</div>
<div>
    python works
</div>

Answer 1

到目前为止，我的解决办法是创建自己的class MyPageTemplate(PageTemplate)，将视图的实例作为构造函数中的参数传递，并覆盖pt_getContext以从实例填充名称空间中的view、context和request。

我想知道是否有更好的解决办法(最佳做法)。

这是我的解决办法：

from plone.app.testing import TEST_USER_NAME
from plone.app.testing import TEST_USER_PASSWORD
from plone.testing.z2 import Browser
from zope.component import getGlobalSiteManager
from zope.publisher.interfaces.browser import IBrowserView
from Products.Five.browser import BrowserView
from Products.Five.browser.pagetemplatefile import ViewPageTemplateFile
from zope.pagetemplate.pagetemplate import PageTemplate
from zope.interface import Interface
from zope.publisher.browser import IDefaultBrowserLayer

class MyPageTemplate(PageTemplate):
    instance = None
    def __init__(self, instance):
        self.instance = instance
    def pt_getContext(self, instance, request, **kw):
        namespace = super(MyPageTemplate, self).pt_getContext(**kw)
        namespace['view'] = self.instance
        namespace['context'] = self.instance.context
        namespace['request'] = self.instance.request
        return namespace

class MyView(BrowserView):
    def __init__(self, context, request):
        self.context = context
        self.request = request
    def render(self):
        template = MyPageTemplate(self)
        text = '''\
<div tal:on-error="string:request fails">request<span tal:replace="structure request"/> works</div>
<div tal:on-error="string:context fails">context/id=<span tal:replace="context/id"/> works</div>
<div tal:on-error="string:view fails">view/my_var=<span tal:replace="view/my_var"/> works</div>
<div tal:on-error="string:python fails"><span tal:replace="python:'python works'"/></div>
            '''
        template.write(text)
        return template()
    def __call__(self):
        return self.render()
    def my_var(self):
        return 'my_value'

global_site_manager = getGlobalSiteManager()
global_site_manager.registerAdapter(MyView, (None, None), IBrowserView, 'my_view')

browser=Browser(app.Plone)
browser.addHeader('Authorization', 'Basic %s:%s' % (TEST_USER_NAME, TEST_USER_PASSWORD))
browser.open(app.Plone.absolute_url() + '/@@my_view')
print browser.contents