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.faults import SfaNotImplemented, InvalidRSpec
10 header = '<?xml version="1.0"?>\n'
11 template = """<RSpec></RSpec>"""
18 def __init__(self, rspec="", namespaces={}, type=None, user_options={}):
20 self.user_options = user_options
22 self.parse_rspec(rspec, namespaces)
30 # eg. 2011-03-23T19:53:28Z
31 date_format = '%Y-%m-%dT%H:%M:%SZ'
32 now = datetime.utcnow()
33 generated_ts = now.strftime(date_format)
34 expires_ts = (now + timedelta(hours=1)).strftime(date_format)
35 self.parse_rspec(self.template, self.namespaces)
36 self.xml.set('expires', expires_ts)
37 self.xml.set('generated', generated_ts)
39 def parse_rspec(self, rspec, namespaces={}):
41 parse rspec into etree
43 parser = etree.XMLParser(remove_blank_text=True)
45 tree = etree.parse(rspec, parser)
47 # 'rspec' file doesnt exist. 'rspec' is proably an xml string
49 tree = etree.parse(StringIO(rspec), parser)
51 raise InvalidRSpec(str(e))
52 self.xml = tree.getroot()
54 self.namespaces = namespaces
56 def xpath(self, xpath):
57 return this.xml.xpath(xpath, namespaces=self.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 if not element_name.startswith('//'):
102 element_name = '//' + element_name
104 elements = root_node.xpath('%s ' % element_name, namespaces=self.namespaces)
105 for element in elements:
106 parent = element.getparent()
107 parent.remove(element)
110 def merge(self, in_rspec):
113 def validate(self, schema):
115 Validate against rng schema
118 relaxng_doc = etree.parse(schema)
119 relaxng = etree.RelaxNG(relaxng_doc)
120 if not relaxng(self.xml):
121 error = relaxng.error_log.last_error
122 message = "%s (line %s)" % (error.message, error.line)
123 raise InvalidRSpec(message)
128 Optional method which inheriting classes can choose to implent.
132 def _process_slivers(self, slivers):
134 Creates a dict of sliver details for each sliver host
136 @param slivers a single hostname, list of hostanmes or list of dicts keys on hostname,
137 Returns a list of dicts
139 if not isinstance(slivers, list):
142 for sliver in slivers:
143 if isinstance(sliver, dict):
145 elif isinstance(sliver, basestring):
146 dicts.append({'hostname': sliver})
152 def toxml(self, cleanup=False):
155 return self.header + etree.tostring(self.xml, pretty_print=True)
157 def save(self, filename):
158 f = open(filename, 'w')
159 f.write(self.toxml())
162 if __name__ == '__main__':