Fixed #4565 -- Changed template rendering to use iterators, rather than
creating large strings, as much as possible. This is all backwards compatible. Thanks, Brian Harring. git-svn-id: http://code.djangoproject.com/svn/django/trunk@5482 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Malcolm Tredinnick
parent
44dd91ec6d
commit
bccb8897e6
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@ -94,15 +94,15 @@ class FieldWidgetNode(template.Node):
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return cls.nodelists[klass]
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get_nodelist = classmethod(get_nodelist)
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def render(self, context):
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def iter_render(self, context):
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bound_field = template.resolve_variable(self.bound_field_var, context)
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context.push()
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context['bound_field'] = bound_field
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output = self.get_nodelist(bound_field.field.__class__).render(context)
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for chunk in self.get_nodelist(bound_field.field.__class__).iter_render(context):
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yield chunk
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context.pop()
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return output
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class FieldWrapper(object):
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def __init__(self, field ):
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@ -157,7 +157,7 @@ class EditInlineNode(template.Node):
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def __init__(self, rel_var):
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self.rel_var = rel_var
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def render(self, context):
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def iter_render(self, context):
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relation = template.resolve_variable(self.rel_var, context)
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context.push()
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if relation.field.rel.edit_inline == models.TABULAR:
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@ -169,10 +169,9 @@ class EditInlineNode(template.Node):
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original = context.get('original', None)
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bound_related_object = relation.bind(context['form'], original, bound_related_object_class)
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context['bound_related_object'] = bound_related_object
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t = loader.get_template(bound_related_object.template_name())
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output = t.render(context)
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for chunk in loader.get_template(bound_related_object.template_name()).iter_render(context):
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yield chunk
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context.pop()
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return output
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def output_all(form_fields):
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return ''.join([str(f) for f in form_fields])
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@ -7,7 +7,7 @@ class AdminApplistNode(template.Node):
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def __init__(self, varname):
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self.varname = varname
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def render(self, context):
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def iter_render(self, context):
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from django.db import models
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from django.utils.text import capfirst
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app_list = []
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@ -54,7 +54,7 @@ class AdminApplistNode(template.Node):
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'models': model_list,
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})
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context[self.varname] = app_list
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return ''
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return ()
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def get_admin_app_list(parser, token):
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"""
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@ -10,14 +10,14 @@ class AdminLogNode(template.Node):
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def __repr__(self):
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return "<GetAdminLog Node>"
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def render(self, context):
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def iter_render(self, context):
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if self.user is None:
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context[self.varname] = LogEntry.objects.all().select_related()[:self.limit]
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else:
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if not self.user.isdigit():
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self.user = context[self.user].id
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context[self.varname] = LogEntry.objects.filter(user__id__exact=self.user).select_related()[:self.limit]
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return ''
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return ()
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class DoGetAdminLog:
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"""
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@ -24,7 +24,7 @@ class CommentFormNode(template.Node):
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self.photo_options, self.rating_options = photo_options, rating_options
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self.is_public = is_public
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def render(self, context):
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def iter_render(self, context):
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from django.conf import settings
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from django.utils.text import normalize_newlines
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import base64
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@ -33,7 +33,7 @@ class CommentFormNode(template.Node):
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try:
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self.obj_id = template.resolve_variable(self.obj_id_lookup_var, context)
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except template.VariableDoesNotExist:
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return ''
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return
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# Validate that this object ID is valid for this content-type.
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# We only have to do this validation if obj_id_lookup_var is provided,
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# because do_comment_form() validates hard-coded object IDs.
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@ -67,9 +67,9 @@ class CommentFormNode(template.Node):
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context['hash'] = Comment.objects.get_security_hash(context['options'], context['photo_options'], context['rating_options'], context['target'])
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context['logout_url'] = settings.LOGOUT_URL
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default_form = loader.get_template(COMMENT_FORM)
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output = default_form.render(context)
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for chunk in default_form.iter_render(context):
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yield chunk
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context.pop()
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return output
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class CommentCountNode(template.Node):
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def __init__(self, package, module, context_var_name, obj_id, var_name, free):
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@ -77,7 +77,7 @@ class CommentCountNode(template.Node):
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self.context_var_name, self.obj_id = context_var_name, obj_id
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self.var_name, self.free = var_name, free
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def render(self, context):
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def iter_render(self, context):
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from django.conf import settings
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manager = self.free and FreeComment.objects or Comment.objects
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if self.context_var_name is not None:
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@ -86,7 +86,7 @@ class CommentCountNode(template.Node):
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content_type__app_label__exact=self.package,
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content_type__model__exact=self.module, site__id__exact=settings.SITE_ID).count()
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context[self.var_name] = comment_count
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return ''
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return ()
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class CommentListNode(template.Node):
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def __init__(self, package, module, context_var_name, obj_id, var_name, free, ordering, extra_kwargs=None):
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@ -96,14 +96,14 @@ class CommentListNode(template.Node):
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self.ordering = ordering
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self.extra_kwargs = extra_kwargs or {}
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def render(self, context):
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def iter_render(self, context):
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from django.conf import settings
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get_list_function = self.free and FreeComment.objects.filter or Comment.objects.get_list_with_karma
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if self.context_var_name is not None:
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try:
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self.obj_id = template.resolve_variable(self.context_var_name, context)
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except template.VariableDoesNotExist:
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return ''
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return ()
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kwargs = {
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'object_id__exact': self.obj_id,
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'content_type__app_label__exact': self.package,
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@ -127,7 +127,7 @@ class CommentListNode(template.Node):
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comment_list = [c for c in comment_list if not c.is_hidden or (user_id == c.user_id)]
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context[self.var_name] = comment_list
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return ''
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return ()
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class DoCommentForm:
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"""
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@ -309,7 +309,7 @@ class ServerHandler(object):
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"""
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if not self.result_is_file() and not self.sendfile():
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for data in self.result:
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self.write(data)
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self.write(data, False)
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self.finish_content()
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self.close()
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@ -377,7 +377,7 @@ class ServerHandler(object):
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else:
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self._write('Status: %s\r\n' % self.status)
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def write(self, data):
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def write(self, data, flush=True):
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"""'write()' callable as specified by PEP 333"""
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assert type(data) is StringType,"write() argument must be string"
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@ -394,7 +394,8 @@ class ServerHandler(object):
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# XXX check Content-Length and truncate if too many bytes written?
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self._write(data)
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self._flush()
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if flush:
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self._flush()
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def sendfile(self):
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"""Platform-specific file transmission
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@ -421,8 +422,6 @@ class ServerHandler(object):
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if not self.headers_sent:
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self.headers['Content-Length'] = "0"
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self.send_headers()
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else:
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pass # XXX check if content-length was too short?
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def close(self):
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try:
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@ -222,6 +222,12 @@ class HttpResponse(object):
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content = ''.join(self._container)
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if isinstance(content, unicode):
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content = content.encode(self._charset)
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# If self._container was an iterator, we have just exhausted it, so we
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# need to save the results for anything else that needs access
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if not self._is_string:
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self._container = [content]
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self._is_string = True
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return content
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def _set_content(self, value):
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@ -231,14 +237,10 @@ class HttpResponse(object):
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content = property(_get_content, _set_content)
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def __iter__(self):
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self._iterator = self._container.__iter__()
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return self
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def next(self):
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chunk = self._iterator.next()
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if isinstance(chunk, unicode):
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chunk = chunk.encode(self._charset)
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return chunk
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for chunk in self._container:
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if isinstance(chunk, unicode):
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chunk = chunk.encode(self._charset)
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yield chunk
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def close(self):
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if hasattr(self._container, 'close'):
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@ -309,6 +309,10 @@ class FormField(object):
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return data
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html2python = staticmethod(html2python)
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def iter_render(self, data):
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# this even needed?
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return (self.render(data),)
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def render(self, data):
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raise NotImplementedError
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@ -7,7 +7,7 @@ from django.http import HttpResponse, Http404
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from django.db.models.manager import Manager
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def render_to_response(*args, **kwargs):
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return HttpResponse(loader.render_to_string(*args, **kwargs))
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return HttpResponse(loader.render_to_iter(*args, **kwargs))
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load_and_render = render_to_response # For backwards compatibility.
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def get_object_or_404(klass, *args, **kwargs):
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@ -55,6 +55,7 @@ times with multiple contexts)
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'\n<html>\n\n</html>\n'
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"""
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import re
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import types
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from inspect import getargspec
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from django.conf import settings
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from django.template.context import Context, RequestContext, ContextPopException
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@ -167,9 +168,12 @@ class Template(object):
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for subnode in node:
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yield subnode
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def render(self, context):
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def iter_render(self, context):
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"Display stage -- can be called many times"
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return self.nodelist.render(context)
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return self.nodelist.iter_render(context)
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def render(self, context):
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return ''.join(self.iter_render(context))
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def compile_string(template_string, origin):
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"Compiles template_string into NodeList ready for rendering"
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@ -698,10 +702,26 @@ def resolve_variable(path, context):
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del bits[0]
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return current
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class NodeBase(type):
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def __new__(cls, name, bases, attrs):
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"""
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Ensures that either a 'render' or 'render_iter' method is defined on
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any Node sub-class. This avoids potential infinite loops at runtime.
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"""
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if not (isinstance(attrs.get('render'), types.FunctionType) or
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isinstance(attrs.get('iter_render'), types.FunctionType)):
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raise TypeError('Unable to create Node subclass without either "render" or "iter_render" method.')
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return type.__new__(cls, name, bases, attrs)
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class Node(object):
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__metaclass__ = NodeBase
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def iter_render(self, context):
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return (self.render(context),)
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def render(self, context):
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"Return the node rendered as a string"
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pass
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return ''.join(self.iter_render(context))
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def __iter__(self):
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yield self
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@ -717,13 +737,12 @@ class Node(object):
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class NodeList(list):
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def render(self, context):
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bits = []
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return ''.join(self.iter_render(context))
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def iter_render(self, context):
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for node in self:
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if isinstance(node, Node):
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bits.append(self.render_node(node, context))
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else:
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bits.append(node)
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return ''.join(bits)
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for chunk in node.iter_render(context):
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yield chunk
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def get_nodes_by_type(self, nodetype):
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"Return a list of all nodes of the given type"
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@ -732,24 +751,26 @@ class NodeList(list):
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nodes.extend(node.get_nodes_by_type(nodetype))
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return nodes
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def render_node(self, node, context):
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return(node.render(context))
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class DebugNodeList(NodeList):
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def render_node(self, node, context):
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try:
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result = node.render(context)
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except TemplateSyntaxError, e:
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if not hasattr(e, 'source'):
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e.source = node.source
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raise
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except Exception, e:
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from sys import exc_info
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wrapped = TemplateSyntaxError('Caught an exception while rendering: %s' % e)
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wrapped.source = node.source
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wrapped.exc_info = exc_info()
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raise wrapped
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return result
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def iter_render(self, context):
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for node in self:
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if not isinstance(node, Node):
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yield node
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continue
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try:
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for chunk in node.iter_render(context):
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yield chunk
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except TemplateSyntaxError, e:
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if not hasattr(e, 'source'):
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e.source = node.source
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raise
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except Exception, e:
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from sys import exc_info
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wrapped = TemplateSyntaxError('Caught an exception while rendering: %s' % e)
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wrapped.source = node.source
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wrapped.exc_info = exc_info()
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raise wrapped
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class TextNode(Node):
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def __init__(self, s):
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@ -758,6 +779,9 @@ class TextNode(Node):
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def __repr__(self):
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return "<Text Node: '%s'>" % self.s[:25]
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def iter_render(self, context):
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return (self.s,)
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def render(self, context):
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return self.s
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@ -781,6 +805,9 @@ class VariableNode(Node):
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else:
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return output
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def iter_render(self, context):
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return (self.render(context),)
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def render(self, context):
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output = self.filter_expression.resolve(context)
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return self.encode_output(output)
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@ -869,6 +896,9 @@ class Library(object):
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def __init__(self, vars_to_resolve):
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self.vars_to_resolve = vars_to_resolve
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#def iter_render(self, context):
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# return (self.render(context),)
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def render(self, context):
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resolved_vars = [resolve_variable(var, context) for var in self.vars_to_resolve]
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return func(*resolved_vars)
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@ -891,7 +921,7 @@ class Library(object):
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def __init__(self, vars_to_resolve):
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self.vars_to_resolve = vars_to_resolve
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def render(self, context):
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def iter_render(self, context):
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resolved_vars = [resolve_variable(var, context) for var in self.vars_to_resolve]
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if takes_context:
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args = [context] + resolved_vars
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@ -907,7 +937,7 @@ class Library(object):
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else:
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t = get_template(file_name)
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self.nodelist = t.nodelist
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return self.nodelist.render(context_class(dict))
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return self.nodelist.iter_render(context_class(dict))
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compile_func = curry(generic_tag_compiler, params, defaults, getattr(func, "_decorated_function", func).__name__, InclusionNode)
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compile_func.__doc__ = func.__doc__
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@ -14,12 +14,11 @@ if not hasattr(__builtins__, 'reversed'):
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for index in xrange(len(data)-1, -1, -1):
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yield data[index]
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register = Library()
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class CommentNode(Node):
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def render(self, context):
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return ''
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def iter_render(self, context):
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return ()
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class CycleNode(Node):
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def __init__(self, cyclevars, variable_name=None):
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@ -28,6 +27,9 @@ class CycleNode(Node):
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self.counter = -1
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self.variable_name = variable_name
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def iter_render(self, context):
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return (self.render(context),)
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def render(self, context):
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self.counter += 1
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value = self.cyclevars[self.counter % self.cyclevars_len]
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@ -36,29 +38,32 @@ class CycleNode(Node):
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return value
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class DebugNode(Node):
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def render(self, context):
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def iter_render(self, context):
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from pprint import pformat
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output = [pformat(val) for val in context]
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output.append('\n\n')
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output.append(pformat(sys.modules))
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return ''.join(output)
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for val in context:
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yield pformat(val)
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yield "\n\n"
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yield pformat(sys.modules)
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class FilterNode(Node):
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def __init__(self, filter_expr, nodelist):
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self.filter_expr, self.nodelist = filter_expr, nodelist
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def render(self, context):
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def iter_render(self, context):
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output = self.nodelist.render(context)
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# apply filters
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context.update({'var': output})
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filtered = self.filter_expr.resolve(context)
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context.pop()
|
||||
return filtered
|
||||
return (filtered,)
|
||||
|
||||
class FirstOfNode(Node):
|
||||
def __init__(self, vars):
|
||||
self.vars = vars
|
||||
|
||||
def iter_render(self, context):
|
||||
return (self.render(context),)
|
||||
|
||||
def render(self, context):
|
||||
for var in self.vars:
|
||||
try:
|
||||
|
|
@ -94,8 +99,7 @@ class ForNode(Node):
|
|||
nodes.extend(self.nodelist_loop.get_nodes_by_type(nodetype))
|
||||
return nodes
|
||||
|
||||
def render(self, context):
|
||||
nodelist = NodeList()
|
||||
def iter_render(self, context):
|
||||
if 'forloop' in context:
|
||||
parentloop = context['forloop']
|
||||
else:
|
||||
|
|
@ -103,12 +107,12 @@ class ForNode(Node):
|
|||
context.push()
|
||||
try:
|
||||
values = self.sequence.resolve(context, True)
|
||||
if values is None:
|
||||
values = ()
|
||||
elif not hasattr(values, '__len__'):
|
||||
values = list(values)
|
||||
except VariableDoesNotExist:
|
||||
values = []
|
||||
if values is None:
|
||||
values = []
|
||||
if not hasattr(values, '__len__'):
|
||||
values = list(values)
|
||||
values = ()
|
||||
len_values = len(values)
|
||||
if self.reversed:
|
||||
values = reversed(values)
|
||||
|
|
@ -127,12 +131,17 @@ class ForNode(Node):
|
|||
'parentloop': parentloop,
|
||||
}
|
||||
if unpack:
|
||||
# If there are multiple loop variables, unpack the item into them.
|
||||
# If there are multiple loop variables, unpack the item into
|
||||
# them.
|
||||
context.update(dict(zip(self.loopvars, item)))
|
||||
else:
|
||||
context[self.loopvars[0]] = item
|
||||
|
||||
# We inline this to avoid the overhead since ForNode is pretty
|
||||
# common.
|
||||
for node in self.nodelist_loop:
|
||||
nodelist.append(node.render(context))
|
||||
for chunk in node.iter_render(context):
|
||||
yield chunk
|
||||
if unpack:
|
||||
# The loop variables were pushed on to the context so pop them
|
||||
# off again. This is necessary because the tag lets the length
|
||||
|
|
@ -141,7 +150,6 @@ class ForNode(Node):
|
|||
# context.
|
||||
context.pop()
|
||||
context.pop()
|
||||
return nodelist.render(context)
|
||||
|
||||
class IfChangedNode(Node):
|
||||
def __init__(self, nodelist, *varlist):
|
||||
|
|
@ -149,7 +157,7 @@ class IfChangedNode(Node):
|
|||
self._last_seen = None
|
||||
self._varlist = varlist
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
if 'forloop' in context and context['forloop']['first']:
|
||||
self._last_seen = None
|
||||
try:
|
||||
|
|
@ -167,11 +175,9 @@ class IfChangedNode(Node):
|
|||
self._last_seen = compare_to
|
||||
context.push()
|
||||
context['ifchanged'] = {'firstloop': firstloop}
|
||||
content = self.nodelist.render(context)
|
||||
for chunk in self.nodelist.iter_render(context):
|
||||
yield chunk
|
||||
context.pop()
|
||||
return content
|
||||
else:
|
||||
return ''
|
||||
|
||||
class IfEqualNode(Node):
|
||||
def __init__(self, var1, var2, nodelist_true, nodelist_false, negate):
|
||||
|
|
@ -182,7 +188,7 @@ class IfEqualNode(Node):
|
|||
def __repr__(self):
|
||||
return "<IfEqualNode>"
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
try:
|
||||
val1 = resolve_variable(self.var1, context)
|
||||
except VariableDoesNotExist:
|
||||
|
|
@ -192,8 +198,8 @@ class IfEqualNode(Node):
|
|||
except VariableDoesNotExist:
|
||||
val2 = None
|
||||
if (self.negate and val1 != val2) or (not self.negate and val1 == val2):
|
||||
return self.nodelist_true.render(context)
|
||||
return self.nodelist_false.render(context)
|
||||
return self.nodelist_true.iter_render(context)
|
||||
return self.nodelist_false.iter_render(context)
|
||||
|
||||
class IfNode(Node):
|
||||
def __init__(self, bool_exprs, nodelist_true, nodelist_false, link_type):
|
||||
|
|
@ -218,7 +224,7 @@ class IfNode(Node):
|
|||
nodes.extend(self.nodelist_false.get_nodes_by_type(nodetype))
|
||||
return nodes
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
if self.link_type == IfNode.LinkTypes.or_:
|
||||
for ifnot, bool_expr in self.bool_exprs:
|
||||
try:
|
||||
|
|
@ -226,8 +232,8 @@ class IfNode(Node):
|
|||
except VariableDoesNotExist:
|
||||
value = None
|
||||
if (value and not ifnot) or (ifnot and not value):
|
||||
return self.nodelist_true.render(context)
|
||||
return self.nodelist_false.render(context)
|
||||
return self.nodelist_true.iter_render(context)
|
||||
return self.nodelist_false.iter_render(context)
|
||||
else:
|
||||
for ifnot, bool_expr in self.bool_exprs:
|
||||
try:
|
||||
|
|
@ -235,8 +241,8 @@ class IfNode(Node):
|
|||
except VariableDoesNotExist:
|
||||
value = None
|
||||
if not ((value and not ifnot) or (ifnot and not value)):
|
||||
return self.nodelist_false.render(context)
|
||||
return self.nodelist_true.render(context)
|
||||
return self.nodelist_false.iter_render(context)
|
||||
return self.nodelist_true.iter_render(context)
|
||||
|
||||
class LinkTypes:
|
||||
and_ = 0,
|
||||
|
|
@ -247,11 +253,11 @@ class RegroupNode(Node):
|
|||
self.target, self.expression = target, expression
|
||||
self.var_name = var_name
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
obj_list = self.target.resolve(context, True)
|
||||
if obj_list == None: # target_var wasn't found in context; fail silently
|
||||
context[self.var_name] = []
|
||||
return ''
|
||||
return ()
|
||||
output = [] # list of dictionaries in the format {'grouper': 'key', 'list': [list of contents]}
|
||||
for obj in obj_list:
|
||||
grouper = self.expression.resolve(obj, True)
|
||||
|
|
@ -261,7 +267,7 @@ class RegroupNode(Node):
|
|||
else:
|
||||
output.append({'grouper': grouper, 'list': [obj]})
|
||||
context[self.var_name] = output
|
||||
return ''
|
||||
return ()
|
||||
|
||||
def include_is_allowed(filepath):
|
||||
for root in settings.ALLOWED_INCLUDE_ROOTS:
|
||||
|
|
@ -273,10 +279,10 @@ class SsiNode(Node):
|
|||
def __init__(self, filepath, parsed):
|
||||
self.filepath, self.parsed = filepath, parsed
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
if not include_is_allowed(self.filepath):
|
||||
if settings.DEBUG:
|
||||
return "[Didn't have permission to include file]"
|
||||
return ("[Didn't have permission to include file]",)
|
||||
else:
|
||||
return '' # Fail silently for invalid includes.
|
||||
try:
|
||||
|
|
@ -287,23 +293,25 @@ class SsiNode(Node):
|
|||
output = ''
|
||||
if self.parsed:
|
||||
try:
|
||||
t = Template(output, name=self.filepath)
|
||||
return t.render(context)
|
||||
return Template(output, name=self.filepath).iter_render(context)
|
||||
except TemplateSyntaxError, e:
|
||||
if settings.DEBUG:
|
||||
return "[Included template had syntax error: %s]" % e
|
||||
else:
|
||||
return '' # Fail silently for invalid included templates.
|
||||
return output
|
||||
return (output,)
|
||||
|
||||
class LoadNode(Node):
|
||||
def render(self, context):
|
||||
return ''
|
||||
def iter_render(self, context):
|
||||
return ()
|
||||
|
||||
class NowNode(Node):
|
||||
def __init__(self, format_string):
|
||||
self.format_string = format_string
|
||||
|
||||
def iter_render(self, context):
|
||||
return (self.render(context),)
|
||||
|
||||
def render(self, context):
|
||||
from datetime import datetime
|
||||
from django.utils.dateformat import DateFormat
|
||||
|
|
@ -332,6 +340,9 @@ class TemplateTagNode(Node):
|
|||
def __init__(self, tagtype):
|
||||
self.tagtype = tagtype
|
||||
|
||||
def iter_render(self, context):
|
||||
return (self.render(context),)
|
||||
|
||||
def render(self, context):
|
||||
return self.mapping.get(self.tagtype, '')
|
||||
|
||||
|
|
@ -341,18 +352,18 @@ class URLNode(Node):
|
|||
self.args = args
|
||||
self.kwargs = kwargs
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
from django.core.urlresolvers import reverse, NoReverseMatch
|
||||
args = [arg.resolve(context) for arg in self.args]
|
||||
kwargs = dict([(k, v.resolve(context)) for k, v in self.kwargs.items()])
|
||||
try:
|
||||
return reverse(self.view_name, args=args, kwargs=kwargs)
|
||||
return (reverse(self.view_name, args=args, kwargs=kwargs),)
|
||||
except NoReverseMatch:
|
||||
try:
|
||||
project_name = settings.SETTINGS_MODULE.split('.')[0]
|
||||
return reverse(project_name + '.' + self.view_name, args=args, kwargs=kwargs)
|
||||
except NoReverseMatch:
|
||||
return ''
|
||||
return ()
|
||||
|
||||
class WidthRatioNode(Node):
|
||||
def __init__(self, val_expr, max_expr, max_width):
|
||||
|
|
@ -360,6 +371,9 @@ class WidthRatioNode(Node):
|
|||
self.max_expr = max_expr
|
||||
self.max_width = max_width
|
||||
|
||||
def iter_render(self, context):
|
||||
return (self.render(context),)
|
||||
|
||||
def render(self, context):
|
||||
try:
|
||||
value = self.val_expr.resolve(context)
|
||||
|
|
@ -383,13 +397,13 @@ class WithNode(Node):
|
|||
def __repr__(self):
|
||||
return "<WithNode>"
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
val = self.var.resolve(context)
|
||||
context.push()
|
||||
context[self.name] = val
|
||||
output = self.nodelist.render(context)
|
||||
for chunk in self.nodelist.iter_render(context):
|
||||
yield chunk
|
||||
context.pop()
|
||||
return output
|
||||
|
||||
#@register.tag
|
||||
def comment(parser, token):
|
||||
|
|
|
|||
|
|
@ -87,14 +87,12 @@ def get_template_from_string(source, origin=None, name=None):
|
|||
"""
|
||||
return Template(source, origin, name)
|
||||
|
||||
def render_to_string(template_name, dictionary=None, context_instance=None):
|
||||
def _render_setup(template_name, dictionary=None, context_instance=None):
|
||||
"""
|
||||
Loads the given template_name and renders it with the given dictionary as
|
||||
context. The template_name may be a string to load a single template using
|
||||
get_template, or it may be a tuple to use select_template to find one of
|
||||
the templates in the list. Returns a string.
|
||||
Common setup code for render_to_string and render_to_iter.
|
||||
"""
|
||||
dictionary = dictionary or {}
|
||||
if dictionary is None:
|
||||
dictionary = {}
|
||||
if isinstance(template_name, (list, tuple)):
|
||||
t = select_template(template_name)
|
||||
else:
|
||||
|
|
@ -103,7 +101,28 @@ def render_to_string(template_name, dictionary=None, context_instance=None):
|
|||
context_instance.update(dictionary)
|
||||
else:
|
||||
context_instance = Context(dictionary)
|
||||
return t.render(context_instance)
|
||||
return t, context_instance
|
||||
|
||||
def render_to_string(template_name, dictionary=None, context_instance=None):
|
||||
"""
|
||||
Loads the given template_name and renders it with the given dictionary as
|
||||
context. The template_name may be a string to load a single template using
|
||||
get_template, or it may be a tuple to use select_template to find one of
|
||||
the templates in the list. Returns a string.
|
||||
"""
|
||||
t, c = _render_setup(template_name, dictionary=dictionary, context_instance=context_instance)
|
||||
return t.render(c)
|
||||
|
||||
def render_to_iter(template_name, dictionary=None, context_instance=None):
|
||||
"""
|
||||
Loads the given template_name and renders it with the given dictionary as
|
||||
context. The template_name may be a string to load a single template using
|
||||
get_template, or it may be a tuple to use select_template to find one of
|
||||
the templates in the list. Returns a string.
|
||||
"""
|
||||
t, c = _render_setup(template_name, dictionary=dictionary, context_instance=context_instance)
|
||||
return t.iter_render(c)
|
||||
|
||||
|
||||
def select_template(template_name_list):
|
||||
"Given a list of template names, returns the first that can be loaded."
|
||||
|
|
|
|||
|
|
@ -15,14 +15,14 @@ class BlockNode(Node):
|
|||
def __repr__(self):
|
||||
return "<Block Node: %s. Contents: %r>" % (self.name, self.nodelist)
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
context.push()
|
||||
# Save context in case of block.super().
|
||||
self.context = context
|
||||
context['block'] = self
|
||||
result = self.nodelist.render(context)
|
||||
for chunk in self.nodelist.iter_render(context):
|
||||
yield chunk
|
||||
context.pop()
|
||||
return result
|
||||
|
||||
def super(self):
|
||||
if self.parent:
|
||||
|
|
@ -59,7 +59,7 @@ class ExtendsNode(Node):
|
|||
else:
|
||||
return get_template_from_string(source, origin, parent)
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
compiled_parent = self.get_parent(context)
|
||||
parent_is_child = isinstance(compiled_parent.nodelist[0], ExtendsNode)
|
||||
parent_blocks = dict([(n.name, n) for n in compiled_parent.nodelist.get_nodes_by_type(BlockNode)])
|
||||
|
|
@ -79,7 +79,7 @@ class ExtendsNode(Node):
|
|||
parent_block.parent = block_node.parent
|
||||
parent_block.add_parent(parent_block.nodelist)
|
||||
parent_block.nodelist = block_node.nodelist
|
||||
return compiled_parent.render(context)
|
||||
return compiled_parent.iter_render(context)
|
||||
|
||||
class ConstantIncludeNode(Node):
|
||||
def __init__(self, template_path):
|
||||
|
|
@ -91,27 +91,26 @@ class ConstantIncludeNode(Node):
|
|||
raise
|
||||
self.template = None
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
if self.template:
|
||||
return self.template.render(context)
|
||||
else:
|
||||
return ''
|
||||
return self.template.iter_render(context)
|
||||
return ()
|
||||
|
||||
class IncludeNode(Node):
|
||||
def __init__(self, template_name):
|
||||
self.template_name = template_name
|
||||
|
||||
def render(self, context):
|
||||
def iter_render(self, context):
|
||||
try:
|
||||
template_name = resolve_variable(self.template_name, context)
|
||||
t = get_template(template_name)
|
||||
return t.render(context)
|
||||
return t.iter_render(context)
|
||||
except TemplateSyntaxError, e:
|
||||
if settings.TEMPLATE_DEBUG:
|
||||
raise
|
||||
return ''
|
||||
return ()
|
||||
except:
|
||||
return '' # Fail silently for invalid included templates.
|
||||
return () # Fail silently for invalid included templates.
|
||||
|
||||
def do_block(parser, token):
|
||||
"""
|
||||
|
|
|
|||
|
|
@ -11,12 +11,21 @@ from django.template import Template
|
|||
TEST_DATABASE_PREFIX = 'test_'
|
||||
|
||||
def instrumented_test_render(self, context):
|
||||
"""An instrumented Template render method, providing a signal
|
||||
that can be intercepted by the test system Client
|
||||
|
||||
"""
|
||||
An instrumented Template render method, providing a signal that can be
|
||||
intercepted by the test system Client.
|
||||
"""
|
||||
dispatcher.send(signal=signals.template_rendered, sender=self, template=self, context=context)
|
||||
return self.nodelist.render(context)
|
||||
|
||||
def instrumented_test_iter_render(self, context):
|
||||
"""
|
||||
An instrumented Template iter_render method, providing a signal that can be
|
||||
intercepted by the test system Client.
|
||||
"""
|
||||
for chunk in self.nodelist.iter_render(context):
|
||||
yield chunk
|
||||
dispatcher.send(signal=signals.template_rendered, sender=self, template=self, context=context)
|
||||
|
||||
class TestSMTPConnection(object):
|
||||
"""A substitute SMTP connection for use during test sessions.
|
||||
|
|
@ -44,7 +53,9 @@ def setup_test_environment():
|
|||
|
||||
"""
|
||||
Template.original_render = Template.render
|
||||
Template.original_iter_render = Template.iter_render
|
||||
Template.render = instrumented_test_render
|
||||
Template.iter_render = instrumented_test_render
|
||||
|
||||
mail.original_SMTPConnection = mail.SMTPConnection
|
||||
mail.SMTPConnection = TestSMTPConnection
|
||||
|
|
@ -59,7 +70,8 @@ def teardown_test_environment():
|
|||
|
||||
"""
|
||||
Template.render = Template.original_render
|
||||
del Template.original_render
|
||||
Template.iter_render = Template.original_iter_render
|
||||
del Template.original_render, Template.original_iter_render
|
||||
|
||||
mail.SMTPConnection = mail.original_SMTPConnection
|
||||
del mail.original_SMTPConnection
|
||||
|
|
|
|||
|
|
@ -137,7 +137,7 @@ def technical_500_response(request, exc_type, exc_value, tb):
|
|||
'template_does_not_exist': template_does_not_exist,
|
||||
'loader_debug_info': loader_debug_info,
|
||||
})
|
||||
return HttpResponseServerError(t.render(c), mimetype='text/html')
|
||||
return HttpResponseServerError(t.iter_render(c), mimetype='text/html')
|
||||
|
||||
def technical_404_response(request, exception):
|
||||
"Create a technical 404 error response. The exception should be the Http404."
|
||||
|
|
@ -160,7 +160,7 @@ def technical_404_response(request, exception):
|
|||
'request_protocol': request.is_secure() and "https" or "http",
|
||||
'settings': get_safe_settings(),
|
||||
})
|
||||
return HttpResponseNotFound(t.render(c), mimetype='text/html')
|
||||
return HttpResponseNotFound(t.iter_render(c), mimetype='text/html')
|
||||
|
||||
def empty_urlconf(request):
|
||||
"Create an empty URLconf 404 error response."
|
||||
|
|
@ -168,7 +168,7 @@ def empty_urlconf(request):
|
|||
c = Context({
|
||||
'project_name': settings.SETTINGS_MODULE.split('.')[0]
|
||||
})
|
||||
return HttpResponseNotFound(t.render(c), mimetype='text/html')
|
||||
return HttpResponseNotFound(t.iter_render(c), mimetype='text/html')
|
||||
|
||||
def _get_lines_from_file(filename, lineno, context_lines, loader=None, module_name=None):
|
||||
"""
|
||||
|
|
|
|||
|
|
@ -76,7 +76,7 @@ def page_not_found(request, template_name='404.html'):
|
|||
The path of the requested URL (e.g., '/app/pages/bad_page/')
|
||||
"""
|
||||
t = loader.get_template(template_name) # You need to create a 404.html template.
|
||||
return http.HttpResponseNotFound(t.render(RequestContext(request, {'request_path': request.path})))
|
||||
return http.HttpResponseNotFound(t.iter_render(RequestContext(request, {'request_path': request.path})))
|
||||
|
||||
def server_error(request, template_name='500.html'):
|
||||
"""
|
||||
|
|
@ -86,4 +86,4 @@ def server_error(request, template_name='500.html'):
|
|||
Context: None
|
||||
"""
|
||||
t = loader.get_template(template_name) # You need to create a 500.html template.
|
||||
return http.HttpResponseServerError(t.render(Context({})))
|
||||
return http.HttpResponseServerError(t.iter_render(Context({})))
|
||||
|
|
|
|||
|
|
@ -68,7 +68,7 @@ def create_object(request, model, template_name=None,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c))
|
||||
return HttpResponse(t.iter_render(c))
|
||||
|
||||
def update_object(request, model, object_id=None, slug=None,
|
||||
slug_field=None, template_name=None, template_loader=loader,
|
||||
|
|
@ -141,7 +141,7 @@ def update_object(request, model, object_id=None, slug=None,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
response = HttpResponse(t.render(c))
|
||||
response = HttpResponse(t.iter_render(c))
|
||||
populate_xheaders(request, response, model, getattr(object, object._meta.pk.attname))
|
||||
return response
|
||||
|
||||
|
|
@ -195,6 +195,6 @@ def delete_object(request, model, post_delete_redirect,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
response = HttpResponse(t.render(c))
|
||||
response = HttpResponse(t.iter_render(c))
|
||||
populate_xheaders(request, response, model, getattr(object, object._meta.pk.attname))
|
||||
return response
|
||||
|
|
|
|||
|
|
@ -44,7 +44,7 @@ def archive_index(request, queryset, date_field, num_latest=15,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def archive_year(request, year, queryset, date_field, template_name=None,
|
||||
template_loader=loader, extra_context=None, allow_empty=False,
|
||||
|
|
@ -92,7 +92,7 @@ def archive_year(request, year, queryset, date_field, template_name=None,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def archive_month(request, year, month, queryset, date_field,
|
||||
month_format='%b', template_name=None, template_loader=loader,
|
||||
|
|
@ -158,7 +158,7 @@ def archive_month(request, year, month, queryset, date_field,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def archive_week(request, year, week, queryset, date_field,
|
||||
template_name=None, template_loader=loader,
|
||||
|
|
@ -206,7 +206,7 @@ def archive_week(request, year, week, queryset, date_field,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def archive_day(request, year, month, day, queryset, date_field,
|
||||
month_format='%b', day_format='%d', template_name=None,
|
||||
|
|
@ -270,7 +270,7 @@ def archive_day(request, year, month, day, queryset, date_field,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def archive_today(request, **kwargs):
|
||||
"""
|
||||
|
|
@ -339,6 +339,6 @@ def object_detail(request, year, month, day, queryset, date_field,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
response = HttpResponse(t.render(c), mimetype=mimetype)
|
||||
response = HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
populate_xheaders(request, response, model, getattr(obj, obj._meta.pk.name))
|
||||
return response
|
||||
|
|
|
|||
|
|
@ -84,7 +84,7 @@ def object_list(request, queryset, paginate_by=None, page=None,
|
|||
model = queryset.model
|
||||
template_name = "%s/%s_list.html" % (model._meta.app_label, model._meta.object_name.lower())
|
||||
t = template_loader.get_template(template_name)
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def object_detail(request, queryset, object_id=None, slug=None,
|
||||
slug_field=None, template_name=None, template_name_field=None,
|
||||
|
|
@ -126,6 +126,6 @@ def object_detail(request, queryset, object_id=None, slug=None,
|
|||
c[key] = value()
|
||||
else:
|
||||
c[key] = value
|
||||
response = HttpResponse(t.render(c), mimetype=mimetype)
|
||||
response = HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
populate_xheaders(request, response, model, getattr(obj, obj._meta.pk.name))
|
||||
return response
|
||||
|
|
|
|||
|
|
@ -15,7 +15,7 @@ def direct_to_template(request, template, extra_context={}, mimetype=None, **kwa
|
|||
dictionary[key] = value
|
||||
c = RequestContext(request, dictionary)
|
||||
t = loader.get_template(template)
|
||||
return HttpResponse(t.render(c), mimetype=mimetype)
|
||||
return HttpResponse(t.iter_render(c), mimetype=mimetype)
|
||||
|
||||
def redirect_to(request, url, **kwargs):
|
||||
"""
|
||||
|
|
|
|||
|
|
@ -92,7 +92,7 @@ def directory_index(path, fullpath):
|
|||
'directory' : path + '/',
|
||||
'file_list' : files,
|
||||
})
|
||||
return HttpResponse(t.render(c))
|
||||
return HttpResponse(t.iter_render(c))
|
||||
|
||||
def was_modified_since(header=None, mtime=0, size=0):
|
||||
"""
|
||||
|
|
|
|||
|
|
@ -219,13 +219,13 @@ be replaced with the name of the invalid variable.
|
|||
|
||||
While ``TEMPLATE_STRING_IF_INVALID`` can be a useful debugging tool,
|
||||
it is a bad idea to turn it on as a 'development default'.
|
||||
|
||||
|
||||
Many templates, including those in the Admin site, rely upon the
|
||||
silence of the template system when a non-existent variable is
|
||||
encountered. If you assign a value other than ``''`` to
|
||||
``TEMPLATE_STRING_IF_INVALID``, you will experience rendering
|
||||
problems with these templates and sites.
|
||||
|
||||
|
||||
Generally, ``TEMPLATE_STRING_IF_INVALID`` should only be enabled
|
||||
in order to debug a specific template problem, then cleared
|
||||
once debugging is complete.
|
||||
|
|
@ -693,14 +693,15 @@ how the compilation works and how the rendering works.
|
|||
|
||||
When Django compiles a template, it splits the raw template text into
|
||||
''nodes''. Each node is an instance of ``django.template.Node`` and has
|
||||
a ``render()`` method. A compiled template is, simply, a list of ``Node``
|
||||
objects. When you call ``render()`` on a compiled template object, the template
|
||||
calls ``render()`` on each ``Node`` in its node list, with the given context.
|
||||
The results are all concatenated together to form the output of the template.
|
||||
either a ``render()`` or ``iter_render()`` method. A compiled template is,
|
||||
simply, a list of ``Node`` objects. When you call ``render()`` on a compiled
|
||||
template object, the template calls ``render()`` on each ``Node`` in its node
|
||||
list, with the given context. The results are all concatenated together to
|
||||
form the output of the template.
|
||||
|
||||
Thus, to define a custom template tag, you specify how the raw template tag is
|
||||
converted into a ``Node`` (the compilation function), and what the node's
|
||||
``render()`` method does.
|
||||
``render()`` or ``iter_render()`` method does.
|
||||
|
||||
Writing the compilation function
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
|
@ -770,7 +771,8 @@ Writing the renderer
|
|||
~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
The second step in writing custom tags is to define a ``Node`` subclass that
|
||||
has a ``render()`` method.
|
||||
has a ``render()`` method (we will discuss the ``iter_render()`` alternative
|
||||
in `Improving rendering speed`_, below).
|
||||
|
||||
Continuing the above example, we need to define ``CurrentTimeNode``::
|
||||
|
||||
|
|
@ -874,7 +876,7 @@ current context, available in the ``render`` method::
|
|||
def __init__(self, date_to_be_formatted, format_string):
|
||||
self.date_to_be_formatted = date_to_be_formatted
|
||||
self.format_string = format_string
|
||||
|
||||
|
||||
def render(self, context):
|
||||
try:
|
||||
actual_date = resolve_variable(self.date_to_be_formatted, context)
|
||||
|
|
@ -1175,6 +1177,48 @@ For more examples of complex rendering, see the source code for ``{% if %}``,
|
|||
|
||||
.. _configuration:
|
||||
|
||||
Improving rendering speed
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
For most practical purposes, the ``render()`` method on a ``Node`` will be
|
||||
sufficient and the simplest way to implement a new tag. However, if your
|
||||
template tag is expected to produce large strings via ``render()``, you can
|
||||
speed up the rendering process (and reduce memory usage) using iterative
|
||||
rendering via the ``iter_render()`` method.
|
||||
|
||||
The ``iter_render()`` method should either be an iterator that yields string
|
||||
chunks, one at a time, or a method that returns a sequence of string chunks.
|
||||
The template renderer will join the successive chunks together when creating
|
||||
the final output. The improvement over the ``render()`` method here is that
|
||||
you do not need to create one large string containing all the output of the
|
||||
``Node``, instead you can produce the output in smaller chunks.
|
||||
|
||||
By way of example, here's a trivial ``Node`` subclass that simply returns the
|
||||
contents of a file it is given::
|
||||
|
||||
class FileNode(Node):
|
||||
def __init__(self, filename):
|
||||
self.filename = filename
|
||||
|
||||
def iter_render(self):
|
||||
for line in file(self.filename):
|
||||
yield line
|
||||
|
||||
For very large files, the full file contents will never be read entirely into
|
||||
memory when this tag is used, which is a useful optimisation.
|
||||
|
||||
If you define an ``iter_render()`` method on your ``Node`` subclass, you do
|
||||
not need to define a ``render()`` method. The reverse is true as well: the
|
||||
default ``Node.iter_render()`` method will call your ``render()`` method if
|
||||
necessary. A useful side-effect of this is that you can develop a new tag
|
||||
using ``render()`` and producing all the output at once, which is easy to
|
||||
debug. Then you can rewrite the method as an iterator, rename it to
|
||||
``iter_render()`` and everything will still work.
|
||||
|
||||
It is compulsory, however, to define *either* ``render()`` or ``iter_render()``
|
||||
in your subclass. If you omit them both, a ``TypeError`` will be raised when
|
||||
the code is imported.
|
||||
|
||||
Configuring the template system in standalone mode
|
||||
==================================================
|
||||
|
||||
|
|
@ -1206,3 +1250,4 @@ is of obvious interest.
|
|||
|
||||
.. _settings file: ../settings/#using-settings-without-the-django-settings-module-environment-variable
|
||||
.. _settings documentation: ../settings/
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue