GeneralizedTime type

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

Creates GeneralizedTime schema or value object.

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

Keyword Arguments:
 
  • value (unicode, str, bytes or GeneralizedTime object) – unicode object (Python 2) or string (Python 3), alternatively string (Python 2) or bytes (Python 3) representing octet-stream of serialised unicode string (note encoding parameter) or GeneralizedTime 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 GeneralizedTime object is used in octet-stream context.
Raises:

PyAsn1Error – On constraint violation or bad initializer.

Note

The GeneralizedTime type models a character string representing date and time in many different formats.

Formal syntax for the GeneralizedTime value is:

  • YYYYMMDDhh[mm[ss[(.|,)ffff]]] standing for a local time, four 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, then a dot (or a comma), and a number for the fractions of second or
  • a string as above followed by the letter “Z” (denoting a UTC time) or
  • a string as above followed by a string (+|-)hh[mm] denoting time zone offset relative to UTC

For example, 20170126120000Z stands for YYYYMMDDHHMMSSZ.

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

Create a modified version of GeneralizedTime schema or value object.

The clone() method accepts the same set arguments as GeneralizedTime class takes on instantiation except that all arguments of the clone() method are optional.

Whatever arguments are supplied, they are used to create a copy of self taking precedence over the ones used to instantiate self.

Note

Due to the immutable nature of the GeneralizedTime object, if no arguments are supplied, no new GeneralizedTime object will be created and self will be returned instead.

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

Create a specialization of GeneralizedTime schema or value object.

The subtype relationship between ASN.1 types has no correlation with subtype relationship between Python types. ASN.1 type is mainly identified by its tag(s) (TagSet) and value range constraints (ConstraintsIntersection). These ASN.1 type properties are implemented as GeneralizedTime attributes.

The subtype() method accepts the same set arguments as GeneralizedTime class takes on instantiation except that all parameters of the subtype() method are optional.

With the exception of the arguments described below, the rest of supplied arguments they are used to create a copy of self taking precedence over the ones used to instantiate self.

The following arguments to subtype() create a ASN.1 subtype out of GeneralizedTime type:

Other Parameters:
 
  • implicitTag (Tag) – Implicitly apply given ASN.1 tag object to self’s TagSet, then use the result as new object’s ASN.1 tag(s).
  • explicitTag (Tag) – Explicitly apply given ASN.1 tag object to self’s TagSet, then use the result as new object’s ASN.1 tag(s).
  • subtypeSpec (ConstraintsIntersection) – Add ASN.1 constraints object to one of the self’s, then use the result as new object’s ASN.1 constraints.
Returns:

new instance of GeneralizedTime schema or value object

Note

Due to the immutable nature of the GeneralizedTime object, if no arguments are supplied, no new GeneralizedTime object will be created and self will be returned instead.

tagSet = <TagSet object at 0x10747e240 tags 0:0:24>

Default TagSet object for GeneralizedTime objects

asDateTime

Create datetime.datetime object from a GeneralizedTime object.

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

Create GeneralizedTime object from a datetime.datetime object.

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

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

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

Python class inheritance relationship is NOT considered.

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

Examine GeneralizedTime 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.

Python class inheritance relationship is NOT considered.

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

Indicate that GeneralizedTime object represents ASN.1 value.

If isValue is False then this object represents just ASN.1 schema.

If isValue is True then, in addition to its ASN.1 schema features, this object can also be used like a Python built-in object (e.g. int, str, dict etc.).

Returns:boolFalse if object represents just ASN.1 schema. True if object represents ASN.1 schema and can be used as a normal value.

Note

There is an important distinction between PyASN1 schema and value objects. The PyASN1 schema objects can only participate in ASN.1 schema-related operations (e.g. defining or testing the structure of the data). Most obvious uses of ASN.1 schema is to guide serialisation codecs whilst encoding/decoding serialised ASN.1 contents.

The PyASN1 value objects can additionally participate in many operations involving regular Python objects (e.g. arithmetic, comprehension etc).