def __getattr__(self, item):
"""If attribute is not a class member, get the value of the EXIF tag of the same name."""
try:
attribute_id = ATTRIBUTE_ID_MAP[item]
except KeyError:
raise AttributeError("unknown image attribute {0}".format(item))
try:
ifd_tag = self.ifd_tags[attribute_id]
except KeyError:
raise AttributeError(ERROR_IMG_NO_ATTR.format(item))
return ifd_tag.read()
def __setattr__(self, key, value):
try:
# Determine if attribute is an IFD tag accessor.
attribute_id = ATTRIBUTE_ID_MAP[key]
except KeyError:
# Attribute is a class member. Set natively.
super(App1MetaData, self).__setattr__(key, value)
else:
try:
ifd_tag = self.ifd_tags[attribute_id]
except KeyError:
raise AttributeError(ERROR_IMG_NO_ATTR.format(key))
ifd_tag.modify(value)
def __delattr__(self, item):
try:
# Determine if attribute is an IFD tag accessor.
attribute_id = ATTRIBUTE_ID_MAP[item]
except KeyError: # pragma: no cover
# Coverage and behavior tested by Image class.
# Attribute is a class member. Delete natively.
super(App1MetaData, self).__delattr__(item)
else:
# Attribute is not a class member. Delete EXIF tag value.
try:
ifd_tag = self.ifd_tags[attribute_id]
except KeyError:
raise AttributeError(ERROR_IMG_NO_ATTR.format(item))
self._delete_ifd_tag(ifd_tag)