File: //lib/python2.7/dns/renderer.pyc
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� Z d � Z d � Z RS( st Helper class for building DNS wire-format messages.
Most applications can use the higher-level L{dns.message.Message}
class and its to_wire() method to generate wire-format messages.
This class is for those applications which need finer control
over the generation of messages.
Typical use::
r = dns.renderer.Renderer(id=1, flags=0x80, max_size=512)
r.add_question(qname, qtype, qclass)
r.add_rrset(dns.renderer.ANSWER, rrset_1)
r.add_rrset(dns.renderer.ANSWER, rrset_2)
r.add_rrset(dns.renderer.AUTHORITY, ns_rrset)
r.add_edns(0, 0, 4096)
r.add_rrset(dns.renderer.ADDTIONAL, ad_rrset_1)
r.add_rrset(dns.renderer.ADDTIONAL, ad_rrset_2)
r.write_header()
r.add_tsig(keyname, secret, 300, 1, 0, '', request_mac)
wire = r.get_wire()
@ivar output: where rendering is written
@type output: cStringIO.StringIO object
@ivar id: the message id
@type id: int
@ivar flags: the message flags
@type flags: int
@ivar max_size: the maximum size of the message
@type max_size: int
@ivar origin: the origin to use when rendering relative names
@type origin: dns.name.Name object
@ivar compress: the compression table
@type compress: dict
@ivar section: the section currently being rendered
@type section: int (dns.renderer.QUESTION, dns.renderer.ANSWER,
dns.renderer.AUTHORITY, or dns.renderer.ADDITIONAL)
@ivar counts: list of the number of RRs in each section
@type counts: int list of length 4
@ivar mac: the MAC of the rendered message (if TSIG was used)
@type mac: string
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| j j d � d | _ d S( s� Initialize a new renderer.
@param id: the message id
@type id: int
@param flags: the DNS message flags
@type flags: int
@param max_size: the maximum message size; the default is 65535.
If rendering results in a message greater than I{max_size},
then L{dns.exception.TooBig} will be raised.
@type max_size: int
@param origin: the origin to use when rendering relative names
@type origin: dns.name.Namem or None.
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R ( ( s" /usr/lib/python2.7/dns/renderer.pyt __init__J s c C s~ | j j | � | j j � g } x9 | j j � D]( \ } } | | k r3 | j | � q3 q3 Wx | D] } | j | =qf Wd S( s� Truncate the output buffer at offset I{where}, and remove any
compression table entries that pointed beyond the truncation
point.
@param where: the offset
@type where: int
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c C s= | j | k r9 | j | k r- t j j � n | | _ n d S( sZ Set the renderer's current section.
Sections must be rendered order: QUESTION, ANSWER, AUTHORITY,
ADDITIONAL. Sections may be empty.
@param section: the section
@type section: int
@raises dns.exception.FormError: an attempt was made to set
a section value less than the current section.
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j � n | j t c d 7<d S( s Add a question to the message.
@param qname: the question name
@type qname: dns.name.Name
@param rdtype: the question rdata type
@type rdtype: int
@param rdclass: the question rdata class
@type rdclass: int
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� n | j | c | 7<d S( s Add the rrset to the specified section.
Any keyword arguments are passed on to the rdataset's to_wire()
routine.
@param section: the section
@type section: int
@param rrset: the rrset
@type rrset: dns.rrset.RRset object
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� n | j | c | 7<d S( s� Add the rdataset to the specified section, using the specified
name as the owner name.
Any keyword arguments are passed on to the rdataset's to_wire()
routine.
@param section: the section
@type section: int
@param name: the owner name
@type name: dns.name.Name object
@param rdataset: the rdataset
@type rdataset: dns.rdataset.Rdataset object
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S( s� Add an EDNS OPT record to the message.
@param edns: The EDNS level to use.
@type edns: int
@param ednsflags: EDNS flag values.
@type ednsflags: int
@param payload: The EDNS sender's payload field, which is the maximum
size of UDP datagram the sender can handle.
@type payload: int
@param options: The EDNS options list
@type options: list of dns.edns.Option instances
@see: RFC 2671
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s� Add a TSIG signature to the message.
@param keyname: the TSIG key name
@type keyname: dns.name.Name object
@param secret: the secret to use
@type secret: string
@param fudge: TSIG time fudge
@type fudge: int
@param id: the message id to encode in the tsig signature
@type id: int
@param tsig_error: TSIG error code; default is 0.
@type tsig_error: int
@param other_data: TSIG other data.
@type other_data: string
@param request_mac: This message is a response to the request which
had the specified MAC.
@type request_mac: string
@param algorithm: the TSIG algorithm to use
@type algorithm: dns.name.Name object
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C st | j j d � | j j t j d | j | j | j d | j d | j d | j d � � | j j d d � d S( s� Write the DNS message header.
Writing the DNS message header is done after all sections
have been rendered, but before the optional TSIG signature
is added.
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@rtype: string
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