ObjectDescriptor type

class pyasn1.type.useful.ObjectDescriptor(value=NoValue(), tagSet=TagSet(), subtypeSpec=ConstraintsIntersection(), encoding='us-ascii')

Creates ObjectDescriptor type or object.

ObjectDescriptor objects are immutable and duck-type Python 2 unicode or Python 3 str. When used in octet-stream context, ObjectDescriptor type assumes “iso-8859-1” encoding.

Parameters:
  • value (unicode, str, bytes or ObjectDescriptor object) – unicode object (Python 2) or string (Python 3), alternatively string (Python 2) or bytes (Python 3) representing octet-stream of serialized unicode string (note encoding parameter) or ObjectDescriptor class instance.
  • tagSet (TagSet) – Object representing non-default ASN.1 tag(s)
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • encoding (str) – Unicode codec ID to encode/decode unicode (Python 2) or str (Python 3) the payload when ObjectDescriptor object is used in octet-stream context.
Raises:

: :py:class:`pyasn1.error.PyAsn1Error` – On constraint violation or bad initializer.

Note

The ObjectDescriptor type models a character string that can accompany the ObjectIdentifier type to serve as a human-friendly annotation for an OBJECT IDENTIFIER.

clone(self, value=NoValue(), tagSet=TagSet(), subtypeSpec=ConstraintsIntersection(), encoding='us-ascii')

Creates a copy of a ObjectDescriptor type or object.

Any parameters to the clone() method will replace corresponding properties of the ObjectDescriptor object.

Parameters:
  • value (unicode, str, bytes or ObjectDescriptor object) – unicode object (Python 2) or string (Python 3), alternatively string (Python 2) or bytes (Python 3) representing octet-stream of serialized unicode string (note encoding parameter) or ObjectDescriptor class instance.
  • tagSet (TagSet) – Object representing non-default ASN.1 tag(s)
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • encoding (str) – Unicode codec ID to encode/decode unicode (Python 2) or str (Python 3) the payload when ObjectDescriptor object is used in octet-stream context.
Returns:

new instance of ObjectDescriptor type/value

subtype(self, value=NoValue(), implicitTag=TagSet(), explicitTag=TagSet(), subtypeSpec=ConstraintsIntersection(), encoding='us-ascii')

Creates a copy of a ObjectDescriptor type or object.

Any parameters to the subtype() method will be added to the corresponding properties of the ObjectDescriptor object.

Parameters:
  • value (unicode, str, bytes or ObjectDescriptor object) – unicode object (Python 2) or string (Python 3), alternatively string (Python 2) or bytes (Python 3) representing octet-stream of serialized unicode string (note encoding parameter) or ObjectDescriptor class instance.
  • implicitTag (Tag) – Implicitly apply given ASN.1 tag object to caller’s TagSet, then use the result as new object’s ASN.1 tag(s).
  • explicitTag (Tag) – Explicitly apply given ASN.1 tag object to caller’s TagSet, then use the result as new object’s ASN.1 tag(s).
  • subtypeSpec (ConstraintsIntersection) – Object representing non-default ASN.1 subtype constraint(s)
  • encoding (str) – Unicode codec ID to encode/decode unicode (Python 2) or str (Python 3) the payload when ObjectDescriptor object is used in octet-stream context.
Returns:

new instance of ObjectDescriptor type/value

tagSet = TagSet((), Tag(tagClass=0, tagFormat=0, tagId=7))

Default TagSet object for ObjectDescriptor objects

isSameTypeWith(other, matchTags=True, matchConstraints=True)

Examine ObjectDescriptor type for equality with other ASN.1 type.

ASN.1 tags (tag) and constraints (constraint) are examined when carrying out ASN.1 types comparison.

No Python inheritance relationship between PyASN1 objects is considered.

Parameters:other (a pyasn1 type object) – Class instance representing ASN.1 type.
Returns:boolTrue if other is ObjectDescriptor type, False otherwise.
isSuperTypeOf(other, matchTags=True, matchConstraints=True)

Examine ObjectDescriptor type for subtype relationship with other ASN.1 type.

ASN.1 tags (tag) and constraints (constraint) are examined when carrying out ASN.1 types comparison.

No Python inheritance relationship between PyASN1 objects is considered.

Parameters:other (a pyasn1 type object) – Class instance representing ASN.1 type.
Returns:boolTrue if other is a subtype of ObjectDescriptor type, False otherwise.
isValue

Indicate if ObjectDescriptor object represents ASN.1 type or ASN.1 value.

In other words, if isValue is True, then the ASN.1 object is initialized.

Returns:boolTrue if object represents ASN.1 value and type, False if object represents just ASN.1 type.

Note

There is an important distinction between PyASN1 type and value objects. The PyASN1 type objects can only participate in ASN.1 type operations (subtyping, comparison etc) and serve as a blueprint for serialization codecs to resolve ambiguous types.

The PyASN1 value objects can additionally participate in most of built-in Python operations.