UTCTime type

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

Creates UTCTime type or object.

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

Parameters:
  • value (unicode, str, bytes or UTCTime 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 UTCTime 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 UTCTime object is used in octet-stream context.
Raises:

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

Note

The UTCTime type models a character string representing date and time.

Formal syntax for the UTCTime value is:

  • YYMMDDhhmm[ss] standing for UTC time, two digits for the year, two for the month, two for the day and two for the hour, followed by two digits for the minutes and two for the seconds if required or
  • a string as above followed by the letter “Z” (denoting a UTC time) or
  • a string as above followed by a string (+|-)hhmm denoting time zone offset relative to UTC

For example, 170126120000Z which stands for YYMMDDHHMMSSZ.

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

Creates a copy of a UTCTime type or object.

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

Parameters:
  • value (unicode, str, bytes or UTCTime 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 UTCTime 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 UTCTime object is used in octet-stream context.
Returns:

new instance of UTCTime type/value

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

Creates a copy of a UTCTime type or object.

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

Parameters:
  • value (unicode, str, bytes or UTCTime 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 UTCTime 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 UTCTime object is used in octet-stream context.
Returns:

new instance of UTCTime type/value

tagSet = TagSet((), Tag(tagClass=0, tagFormat=0, tagId=23))

Default TagSet object for UTCTime objects

asDateTime

Create datetime.datetime object from a UTCTime object.

Returns:new instance of datetime.datetime object
fromDateTime(dt)

Create UTCTime object from a datetime.datetime object.

Parameters:dt (datetime.datetime object) – The datetime.datetime object to initialize the UTCTime object from
Returns:new instance of UTCTime value
isSameTypeWith(other, matchTags=True, matchConstraints=True)

Examine UTCTime 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 UTCTime type, False otherwise.
isSuperTypeOf(other, matchTags=True, matchConstraints=True)

Examine UTCTime 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 UTCTime type, False otherwise.
isValue

Indicate if UTCTime 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.