plone - 特定宽度/高度的图像字段验证器

Question

我有灵巧型，图像字段定义如下:

image = NamedBlobImage(
    title=_(u'Lead Image'),
    description=_(u"Upload a Image of Size 230x230."),
    required=True,
)

如何添加验证器来检查上传的图像文件？例如，如果图像宽度超过 500 像素，则警告用户上传另一个文件。感谢提示或示例代码。

Answer 1

您要设置约束函数:

from zope.interface import Invalid
from foo.bar import MessageFactory as _


def imageSizeConstraint(value):
    # value implements the plone.namedfile.interfaces.INamedBlobImageField interface
    width, height = value.getImageSize()
    if width > 500 or height > 500:
        raise Invalid(_(u"Your image is too large"))

然后将该函数设置为 NamedBlobImage 字段的约束:

image = NamedBlobImage(
    title=_(u'Lead Image'),
    description=_(u"Upload a Image of Size 230x230."),
    constraint=imageSizeConstraint,
    required=True,
)

请参阅Dexterity manual on validation欲了解更多信息，以及 plone.namedfile interface definitions .