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={}, type=None, user_options={}):
22 self.user_options = user_options
24 self.parse_rspec(rspec, namespaces)
32 # eg. 2011-03-23T19:53:28Z
33 date_format = '%Y-%m-%dT%H:%M:%SZ'
34 now = datetime.utcnow()
35 generated_ts = now.strftime(date_format)
36 expires_ts = (now + timedelta(hours=1)).strftime(date_format)
37 self.parse_rspec(self.template, self.namespaces)
38 self.xml.set('expires', expires_ts)
39 self.xml.set('generated', generated_ts)
41 def parse_rspec(self, rspec, namespaces={}):
43 parse rspec into etree
45 parser = etree.XMLParser(remove_blank_text=True)
47 tree = etree.parse(rspec, parser)
49 # 'rspec' file doesnt exist. 'rspec' is proably an xml string
51 tree = etree.parse(StringIO(rspec), parser)
53 raise InvalidRSpec('Must specify a xml file or xml string. Received: ' + rspec )
55 self.xml = tree.getroot()
57 self.namespaces = namespaces
59 def add_attribute(self, elem, name, value):
61 Add attribute to specified etree element
63 opt = etree.SubElement(elem, name)
66 def add_element(self, name, attrs={}, parent=None, text=""):
68 Generic wrapper around etree.SubElement(). Adds an element to
69 specified parent node. Adds element to root node is parent is
74 element = etree.SubElement(parent, name)
77 if isinstance(attrs, dict):
79 element.set(attr, attrs[attr])
82 def remove_attribute(self, elem, name, value):
84 Removes an attribute from an element
87 opts = elem.iterfind(name)
93 def remove_element(self, element_name, root_node = None):
95 Removes all occurences of an element from the tree. Start at
96 specified root_node if specified, otherwise start at tree's root.
101 elements = root_node.xpath('//rspecv2:%s | //%s' % (element_name, element_name), \
103 for element in elements:
104 parent = element.getparent()
105 parent.remove(element)
108 def merge(self, in_rspec):
111 def validate(self, schema):
113 Validate against rng schema
116 relaxng_doc = etree.parse(schema)
117 relaxng = etree.RelaxNG(relaxng_doc)
118 if not relaxng(self.xml):
119 error = relaxng.error_log.last_error
120 message = "%s (line %s)" % (error.message, error.line)
121 raise InvalidRSpec(message)
129 return self.header + etree.tostring(self.xml, pretty_print=True)
131 def save(self, filename):
132 f = open(filename, 'w')
133 f.write(self.toxml())
136 if __name__ == '__main__':