Class AVA

object --+
         |
        AVA

An object representing an AVA (attribute value assertion).

AVA(type, value)

:Parameters:
     type : may be one of integer, string, SecItem
         What kind of attribute is being created. May be
         one of:

         * integer: A SEC OID enumeration constant (i.e. SEC_OID_*)
           for example SEC_OID_AVA_COMMON_NAME.
         * string: A string either as the ava name, for example 'cn'
           or as the dotted decimal representation, for example
           'OID.2.5.4.3'. Case is not significant for either form.
         * SecItem: A SecItem object encapsulating the OID in 
           DER format.
     value : string
         The value of the AVA, must be a string.

RDN's (Relative Distinguished Name) are composed from AVA's.
An `RDN` is a sequence of AVA's.

An example of an AVA is "CN=www.redhat.com" where CN is the X500
directory abbrevation for "Common Name".

An AVA is composed of two items:

type
    Specifies the attribute (e.g. CN). AVA types are specified by
    predefined OID's (Object Identifiers). For example the OID of CN
    is 2.5.4.3 ({joint-iso-itu-t(2) ds(5) attributeType(4) commonName(3)})
    OID's in NSS are encapsulated in a SecItem as a DER encoded OID.
    Because DER encoded OID's are less than ideal mechanisms by which
    to specify an item NSS has mapped each OID to a integral enumerated
    constant called an OID tag (i.e. SEC_OID_*). Many of the NSS API's
    will accept an OID tag number instead of DER encoded OID in a SecItem.
    One can easily convert between DER encoded OID's, tags, and their
    string representation in dotted-decimal format. The enumerated OID
    constants are the most efficient in most cases.
value
    The value of the attribute (e.g. 'www.redhat.com').

Examples::

    The AVA cn=www.redhat.com can be created in any of the follow ways:

    ava = nss.AVA('cn', 'www.redhat.com')
    ava = nss.AVA(nss.SEC_OID_AVA_COMMON_NAME, 'www.redhat.com')
    ava = nss.AVA('2.5.4.3', 'www.redhat.com')
    ava = nss.AVA('OID.2.5.4.3', 'www.redhat.com')

a new object with type S, a subtype of T

x.__init__(...) initializes x; see x.__class__.__doc__ for signature

repr(x)

The OID (e.g. type) of the AVA as a SecItem

The OID tag enumerated constant (i.e. SEC_OID_AVA_*) of the AVA's type