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>"""
20 def __init__(self, rspec="", namespaces={}, user_options={}):
21 self.user_options = user_options
23 self.parse_rspec(rspec, namespaces)
27 def create(self, type="advertisement"):
31 # eg. 2011-03-23T19:53:28Z
32 date_format = '%Y-%m-%dT%H:%M:%SZ'
33 now = datetime.utcnow()
34 generated_ts = now.strftime(date_format)
35 expires_ts = (now + timedelta(hours=1)).strftime(date_format)
36 self.parse_rspec(self.template, self.namespaces)
37 self.xml.set('valid_until', expires_ts)
38 self.xml.set('generated', generated_ts)
40 def parse_rspec(self, rspec, namespaces={}):
42 parse rspec into etree
44 parser = etree.XMLParser(remove_blank_text=True)
46 tree = etree.parse(rspec, parser)
48 # 'rspec' file doesnt exist. 'rspec' is proably an xml string
50 tree = etree.parse(StringIO(rspec), parser)
52 raise InvalidRSpec('Must specify a xml file or xml string. Received: ' + rspec )
54 self.xml = tree.getroot()
56 self.namespaces = namespaces
58 def add_attribute(self, elem, name, value):
60 Add attribute to specified etree element
62 opt = etree.SubElement(elem, name)
65 def add_element(self, name, attrs={}, parent=None, text=""):
67 Generic wrapper around etree.SubElement(). Adds an element to
68 specified parent node. Adds element to root node is parent is
73 element = etree.SubElement(parent, name)
76 if isinstance(attrs, dict):
78 element.set(attr, attrs[attr])
81 def remove_attribute(self, elem, name, value):
83 Removes an attribute from an element
86 opts = elem.iterfind(name)
92 def merge(self, in_rspec):
95 def validate(self, schema):
97 Validate against rng schema
100 relaxng_doc = etree.parse(schema)
101 relaxng = etree.RelaxNG(relaxng_doc)
102 if not relaxng(self.xml):
103 error = relaxng.error_log.last_error
104 message = "%s (line %s)" % (error.message, error.line)
105 raise InvalidRSpec(message)
113 return self.header + etree.tostring(self.xml, pretty_print=True)
115 def save(self, filename):
116 f = open(filename, 'w')
117 f.write(self.toxml())
120 if __name__ == '__main__':