3 from StringIO import StringIO
4 from datetime import datetime, timedelta
5 from sfa.util.xrn import *
6 from sfa.util.plxrn import hostname_to_urn
7 from sfa.util.config import Config
8 from sfa.util.faults import SfaNotImplemented, InvalidRSpec
11 header = '<?xml version="1.0"?>\n'
12 template = """<RSpec></RSpec>"""
19 def __init__(self, rspec="", namespaces={}):
21 self.parse_rspec(rspec, namespaces)
25 def create(self, type="advertisement"):
29 # eg. 2011-03-23T19:53:28Z
30 date_format = '%Y-%m-%dT%H:%M:%SZ'
31 now = datetime.utcnow()
32 generated_ts = now.strftime(date_format)
33 expires_ts = (now + timedelta(hours=1)).strftime(date_format)
34 self.parse_rspec(self.template, self.namespaces)
35 self.xml.set('valid_until', expires_ts)
36 self.xml.set('generated', generated_ts)
38 def parse_rspec(self, rspec, namespaces={}):
40 parse rspec into etree
42 parser = etree.XMLParser(remove_blank_text=True)
44 tree = etree.parse(rspec, parser)
46 # 'rspec' file doesnt exist. 'rspec' is proably an xml string
48 tree = etree.parse(StringIO(rspec), parser)
50 raise InvalidRSpec('Must specify a xml file or xml string. Received: ' + rspec )
52 self.xml = tree.getroot()
54 self.namespaces = namespaces
56 def add_attribute(self, elem, name, value):
58 Add attribute to specified etree element
60 opt = etree.SubElement(elem, name)
63 def add_element(self, name, attrs={}, parent=None, text=""):
65 Generic wrapper around etree.SubElement(). Adds an element to
66 specified parent node. Adds element to root node is parent is
71 element = etree.SubElement(parent, name)
74 if isinstance(attrs, dict):
76 element.set(attr, attrs[attr])
79 def remove_attribute(self, elem, name, value):
81 Removes an attribute from an element
84 opts = elem.iterfind(name)
90 def merge(self, in_rspec):
93 def validate(self, schema):
95 Validate against rng schema
98 relaxng_doc = etree.parse(schema)
99 relaxng = etree.RelaxNG(relaxng_doc)
100 if not relaxng(self.xml):
101 error = relaxng.error_log.last_error
102 message = "%s (line %s)" % (error.message, error.line)
103 raise InvalidRSpec(message)
111 return self.header + etree.tostring(self.xml, pretty_print=True)
113 def save(self, filename):
114 f = open(filename, 'w')
115 f.write(self.toxml())
118 if __name__ == '__main__':