Smartposter Record

The NFC Forum Smart Poster Record Type Definition defines a structure that associates an Internationalized Resource Identifier (or Uniform Resource Identifier) with various types of metadata. For a user this is most noteably the ability to attach descriptive text in different languages as well as image data for icon rendering. For a smartposter application this is a recommendation for processing as well as resource type and size hints to guide a strategy for retrieving the resource.

class ndef.SmartposterRecord(resource, title=None, action=None, icon=None, resource_size=None, resource_type=None)

Initialize a SmartposterRecord instance. The only required argument is the Internationalized Resource Identifier resource, all other arguments are optional metadata.

Parameters:
  • resource (str) – Internationalized Resource Identifier
  • title (str or dict) – English title str or dict with language keys and title values
  • action (str or int) – assigns a value to the action attribute
  • icon (bytes or dict) – PNG data bytes or dict with {icon-type: icon_data} items
  • resource_size (int) – assigns a value to the resource_size attribute
  • resource_type (str) – assigns a value to the resource_type attribute
type

The Smartposter Record type is urn:nfc:wkt:Sp.

name

Value of the NDEF Record ID field, an empty str if not set.

data

A bytes object containing the NDEF Record PAYLOAD encoded from the current attributes.

resource

Get or set the Smartposter resource identifier. A set value is interpreted as an internationalized resource identifier (so it can be unicode). When reading, the resource attribute returns a UriRecord which can be used to set the UriRecord.iri and UriRecord.uri directly.

title

The title string for language code ‘en’ or the first title string that was decoded or set. If no title string is available the value is None. The attribute can not be set, use set_title().

titles

A dictionary of all decoded or set titles with language str keys and title str values. The attribute can not be set, use set_title().

set_title(title, language='en', encoding='UTF-8')

Set the title string for a specific language which defaults to ‘en’. The transfer encoding may be set to either ‘UTF-8’ or ‘UTF-16’, the default is ‘UTF-8’.

action

Get or set the recommended action for handling the Smartposter resource. A set value may be ‘exec’, ‘save’, ‘edit’ or an index thereof. A read value is either one of above strings or None if no action value was decoded or set.

icon

The image data bytes for an ‘image/png’ type smartposter icon or the first icon decoded or added. If no icon is available the value is None. The attribute can not be set, use add_icon().

icons

A dictionary of icon images with mime-type str keys and icon-data bytes values. The attribute can not be set, use add_icon().

add_icon(icon_type, icon_data)

Add a Smartposter icon as icon_data bytes for the image or video mime-type string supplied with icon_type.

resource_size

Get or set the int size hint for the Smartposter resource. None if a size hint was not decoded or set.

resource_type

Get or set the str type hint for the Smartposter resource. None if a type hint was not decoded or set.

>>> import ndef
>>> record = ndef.SmartposterRecord('https://github.com/nfcpy/ndeflib')
>>> record.set_title('Python package for parsing and generating NDEF', 'en')
>>> record.resource_type = 'text/html'
>>> record.resource_size = 1193970
>>> record.action = 'exec'
>>> len(b''.join(ndef.message_encoder([record])))
115