Python base.Variable類代碼示例

    def __init__(self, parser, token):  # noqa D102
        bits = token.split_contents()

        if len(bits) > 5:
            raise TemplateSyntaxError(
                "%r accepts at most 4 arguments (part_id, section,"
                " asvar, varname), got: {}".format(bits[0], ','.join(bits[1:]))
            )

        self.part_id = Variable(bits[1])
        self.section = bits[2] if len(bits) >= 3 else None

        self.varname = None
        if len(bits) > 3:
            if bits[3] != 'asvar':
                raise TemplateSyntaxError(
                    'Forth argument should be asvar," " got {}'.format(bits[3])
                )
            if len(bits) < 4:
                raise TemplateSyntaxError('Variable name not provided')
            else:
                self.varname = Variable(bits[4])

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

 def render(self, context):
     try:
         actual_object = Variable(self.object_to_get_absolute_url).resolve(context)
         absolute_url = actual_object.get_absolute_url()
         return self.get_admin_absolute_url(absolute_url)
     except VariableDoesNotExist:
         return ''

class FormPartNode(Node):
    """
    Named piece of HTML layout.
    """
    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) > 5:
            raise TemplateSyntaxError(
                "%r accepts at most 4 arguments (part_id, section, asvar, varname), got: {}" %
                (bits[0], ','.join(bits[1:])))

        self.part_id = Variable(bits[1])
        self.section = bits[2] if len(bits) >= 3 else None

        self.varname = None
        if len(bits) > 3:
            if bits[3] != 'asvar':
                raise TemplateSyntaxError('Forth argument should be asvar, got {}', format(bits[3]))
            if len(bits) < 4:
                raise TemplateSyntaxError('Variable name not provided')
            else:
                self.varname = Variable(bits[4])

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

    def resolve_part(self, context):
        part = self.part_id.resolve(context)
        if isinstance(part, BoundField):
            part = part.field
        return part

    def render(self, context):
        part = self.resolve_part(context)
        parts = context['form_parts']

        if self.section in parts[part]:
            # already rendered
            if self.varname is not None:
                context[self.varname.resolve(context)] = parts[part][self.section]
                return ""
            else:
                return parts[part][self.section]

        # child parts
        children = (node for node in self.nodelist if isinstance(node, FormPartNode))
        _render_parts(context, children)

        # render own content
        value = self.nodelist.render(context).strip()
        if self.varname is not None:
            context[self.varname.resolve(context)] = value
            return ''
        else:
            if not value:
                return ''
            return value

 def render(self, context):
     dict = Variable(self.dict).resolve(context)
     key = context.get(self.key, self.key)
     default = context.get(self.default, self.default)
     if dict:
         context[self.context_key] = dict.get(key, default)
     else:
         context[self.context_key] = default
     return ''

class WidgetAttrNode(Node):
    """
    {% attr form.email 'widget' 'data-validate' %}email{% endattr %}
    {% attr form.email 'widget' 'class' append %}green{%  endattr %}
    {% attr form.email 'widget' 'required' %}True{%  endattr %}
    """
    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) < 4:
            raise TemplateSyntaxError(
                "{} accepts at least 3 arguments (bound_field, 'groupname' 'attr_name'), got: {}".format(
                    (bits[0], ','.join(bits[1:]))))

        if len(bits) > 5:
            raise TemplateSyntaxError(
                "{} accepts at mast 4 arguments (bound_field, 'groupname' 'attr_name' action ), got: {}".format(
                    (bits[0], ','.join(bits[1:]))))

        if len(bits) >= 5 and bits[4] not in ['append', 'override']:
            raise TemplateSyntaxError(
                "{} unknown action {}  should be 'append' of 'override'".format(
                    (bits[0], ','.join(bits[4]))))

        self.field = Variable(bits[1])
        self.group = Variable(bits[2])
        self.attr = bits[3]
        self.action = bits[4] if len(bits) >= 5 else 'override'
        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

    def resolve_field(self, context):
        field = self.field.resolve(context)
        if isinstance(field, BoundField):
            field = field.field
        return field

    def render(self, context):
        field = self.resolve_field(context)
        group = self.group.resolve(context)
        form_widget_attrs = context['form_widget_attrs']
        value = self.nodelist.render(context)

        if group not in form_widget_attrs[field]:
            form_widget_attrs[field][group] = {}
        attrs = form_widget_attrs[field][group]

        if self.attr not in attrs or self.action == 'override':
            attrs[self.attr] = (value, self.action)
        else:
            old_value, old_action = attrs[self.attr]
            if old_action != 'override':
                attrs[self.attr] = ('{} {}'.format(old_value, value), self.action)

 def render(self, context):
     request = context.get('request')
     if request:
         form_object = Variable(self.form_object_variable).resolve(context)
         if request.method == "GET":
             form = form_object.empty_form()
         elif request.method == "POST":
             form_object.process_form(request)
             form = form_object.bound_form
     else:
         form = None
     context[self.varname] = form
     return ''

class _ABTestNode(Node):

    def __init__(self, ab_test_name, variant_a_content, variant_b_content):
        self.ab_test_name = Variable(ab_test_name)
        self.variant_a_content = variant_a_content
        self.variant_b_content = variant_b_content

    def render(self, context):
        ab_test_name = self.ab_test_name.resolve(context)
        ab_test = ABTest.objects.get_or_create(name=ab_test_name)[0]

        block_context = context.copy()
        block_context["ab_test"] = ab_test

        if self._is_variant_a_applicable(context["request"]):
            block_context["ab_test_variant"] = VARIANT_A
            content = self.variant_a_content.render(block_context)
            ab_test.times_a_presented += 1
        else:
            block_context["ab_test_variant"] = VARIANT_B
            content = self.variant_b_content.render(block_context)
            ab_test.times_b_presented += 1

        ab_test.save()

        return content

    @staticmethod
    def _is_variant_a_applicable(request):
        raise NotImplementedError("Determine whether A or B is applicable!")

    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) == 0:
            raise TemplateSyntaxError(
                "%r received invalid args, expected one element for render. Got: %r" %
                (bits[0], bits[1:]))

        remaining_bits = bits[2:]

        self.kwargs = token_kwargs(remaining_bits, parser)

        if remaining_bits:
            raise TemplateSyntaxError("%r received an invalid token: %r" %
                                      (bits[0], remaining_bits[0]))

        for key in self.kwargs:
            if key not in ('template', 'widget'):
                raise TemplateSyntaxError("%r received an invalid key: %r" %
                                          (bits[0], key))

            self.kwargs[key] = self.kwargs[key]

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

        self.element = Variable(bits[1])

    def render(self, context):
        provider = Variable(self.provider).resolve(context)
        media = forms.Media(css = widgets.CategorySelectWidget.Media.css, \
                            js = widgets.CategorySelectWidget.Media.js)
        context[self.media_key] = media
        attrs = {
            'id': 'category-tree-{0}'.format(slugify(provider)),
            'class' : 'category-tree',
        }
        for key, value in self.attrs.items():
            if self.attrs[key] == True:
                attrs[key] = True
            else:
                attrs[key] = Variable(value).resolve(context)
        root = None
        if self.root:
            root = Variable(self.root).resolve(context)
        if self.template_name is None:
            template_name = 'category/render-tree.html'
        else:
            template_name = Variable(self.template_name).resolve(context)

        provider = cache.get_object(provider)
        if root:
            if isinstance(root, Category):
                if root.is_root:
                    root = root
                else:
                    root = root.root
            else:
                root = get_root(name = root)
        else:
            root = provider.get_root_category()
        cache.add_object(provider, root.pk)
        kw = {
            'template_name':template_name,
            'context': context,
            'collapse': self.collapse,
            'attrs' : attrs,
        }
        return do_render_tree(provider, root, **kw)

class FormRenderNode(Node):
    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) == 0:
            raise TemplateSyntaxError(
                "%r received invalid args, expected one element for render. Got: %r" %
                (bits[0], bits[1:]))

        remaining_bits = bits[2:]

        self.kwargs = token_kwargs(remaining_bits, parser)

        if remaining_bits:
            raise TemplateSyntaxError("%r received an invalid token: %r" %
                                      (bits[0], remaining_bits[0]))

        for key in self.kwargs:
            if key not in ('template', 'widget'):
                raise TemplateSyntaxError("%r received an invalid key: %r" %
                                          (bits[0], key))

            self.kwargs[key] = self.kwargs[key]

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

        self.element = Variable(bits[1])

    def render(self, context):
        element = self.element.resolve(context)

        options = {}
        for key, value in self.kwargs.items():
            options[key] = value.resolve(context)

        # render inner parts
        children = (node for node in self.nodelist if isinstance(node, FormPartNode))
        _render_parts(context, children)

        attrs = (node for node in self.nodelist if isinstance(node, WidgetAttrNode))
        for attr in attrs:
            attr.render(context)

        # render element
        if isinstance(element, BoundField):
            return Field(element.name).render(context, **options)
        elif hasattr(element, 'render'):
            with context.push(parent=element):
                return element.render(context, **options)
        else:
            raise TemplateSyntaxError("form_render can't render %r" % (element, ))

    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) > 3:
            raise TemplateSyntaxError(
                "%r accepts at most 2 arguments (part_id, section), got: {}" %
                (bits[0], bits[1:]))

        self.part_id = Variable(bits[1])
        self.section = bits[2] if len(bits) == 3 else None

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

class IncludeNode(Node):
    def __init__(self, template_name):
        self.template_name = Variable(template_name)

    def render(self, context):
        try:
            template_name = self.template_name.resolve(context)
            t = get_template(template_name)
            return t.render(context)
        except TemplateSyntaxError, e:
            if settings.TEMPLATE_DEBUG:
                raise
            return ''
        except:

class FormPartNode(Node):
    def __init__(self, parser, token):
        bits = token.split_contents()

        if len(bits) > 3:
            raise TemplateSyntaxError(
                "%r accepts at most 2 arguments (part_id, section), got: {}" %
                (bits[0], bits[1:]))

        self.part_id = Variable(bits[1])
        self.section = bits[2] if len(bits) == 3 else None

        self.nodelist = parser.parse(('end{}'.format(bits[0]),))
        parser.delete_first_token()

    def resolve_part(self, context):
        part = self.part_id.resolve(context)
        if isinstance(part, BoundField):
            part = part.field
        return part

    def render(self, context):
        part = self.resolve_part(context)
        parts = context['form_parts']

        if self.section in parts[part]:
            # already rendered
            return parts[part][self.section]

        # child parts
        children = (node for node in self.nodelist if isinstance(node, FormPartNode))
        _render_parts(context, children)

        # render own content
        value = self.nodelist.render(context)
        if not value.strip():
            return ''
        return value

 def __init__(self, ab_test_name, variant_a_content, variant_b_content):
     self.ab_test_name = Variable(ab_test_name)
     self.variant_a_content = variant_a_content
     self.variant_b_content = variant_b_content

class WidgetAttrNode(Node):
    """The tag allows to add or override specific attribute in the rendered HTML.

    The first argumnent is the attribute group name, second is the
    attribute name.  The third optional flag shows to override (by
    default) or `append` the value.

    Usage::

        {% attr form.email 'widget' 'data-validate' %}email{% endattr %}
        {% attr form.email 'widget' 'class' append %}green{%  endattr %}
        {% attr form.email 'widget' 'required' %}True{%  endattr %}

    """

    def __init__(self, parser, token):  # noqa D102
        bits = token.split_contents()

        if len(bits) < 4:
            raise TemplateSyntaxError(
                "{} accepts at least 3 arguments (bound_field, 'groupname'"
                " 'attr_name'), got: {}".format(bits[0], ','.join(bits[1:]))
            )

        if len(bits) > 5:
            raise TemplateSyntaxError(
                "{} accepts at mast 4 arguments (bound_field, 'groupname'"
                " 'attr_name' action ), got: {}".format(
                    bits[0], ','.join(bits[1:]))
            )

        if len(bits) >= 5 and bits[4] not in ['append', 'override']:
            raise TemplateSyntaxError(
                "{} unknown action {}  should be 'append'"
                " of 'override'".format(bits[0], ','.join(bits[4]))
            )

        self.field = Variable(bits[1])
        self.group = Variable(bits[2])
        self.attr = bits[3]
        self.action = bits[4] if len(bits) >= 5 else 'override'
        self.nodelist = parser.parse(('end{}'.format(bits[0])))
        parser.delete_first_token()

    def resolve_field(self, context):
        """Resolve field reference form context."""
        field = self.field.resolve(context)
        if isinstance(field, BoundField):
            field = field.field
        return field

    def render(self, context):  # noqa D102
        field = self.resolve_field(context)
        group = self.group.resolve(context)
        form_widget_attrs = context['form_widget_attrs']
        value = self.nodelist.render(context)

        if group not in form_widget_attrs[field]:
            form_widget_attrs[field][group] = {}
        attrs = form_widget_attrs[field][group]

        if self.attr not in attrs or self.action == 'override':
            attrs[self.attr] = (value, self.action)
        else:
            old_value, old_action = attrs[self.attr]
            if old_action != 'override':
                attrs[self.attr] = (
                    '{} {}'.format(old_value, value),
                    self.action
                )