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 )
54 self.xml = tree.getroot()
56 self.namespaces = namespaces
58 def xpath(self, xpath):
59 return this.xml.xpath(xpath, namespaces=self.namespaces)
61 def add_attribute(self, elem, name, value):
63 Add attribute to specified etree element
65 opt = etree.SubElement(elem, name)
68 def add_element(self, name, attrs={}, parent=None, text=""):
70 Generic wrapper around etree.SubElement(). Adds an element to
71 specified parent node. Adds element to root node is parent is
76 element = etree.SubElement(parent, name)
79 if isinstance(attrs, dict):
81 element.set(attr, attrs[attr])
84 def remove_attribute(self, elem, name, value):
86 Removes an attribute from an element
89 opts = elem.iterfind(name)
95 def remove_element(self, element_name, root_node = None):
97 Removes all occurences of an element from the tree. Start at
98 specified root_node if specified, otherwise start at tree's root.
103 if not element_name.startswith('//'):
104 element_name = '//' + element_name
106 elements = root_node.xpath('%s ' % element_name, namespaces=self.namespaces)
107 for element in elements:
108 parent = element.getparent()
109 parent.remove(element)
112 def merge(self, in_rspec):
115 def validate(self, schema):
117 Validate against rng schema
120 relaxng_doc = etree.parse(schema)
121 relaxng = etree.RelaxNG(relaxng_doc)
122 if not relaxng(self.xml):
123 error = relaxng.error_log.last_error
124 message = "%s (line %s)" % (error.message, error.line)
125 raise InvalidRSpec(message)
130 Optional method which inheriting classes can choose to implent.
134 def __process_slivers(self, slivers):
136 Creates a dict of sliver details for each sliver host
138 @param slivers a single hostname, list of hostanmes or list of dicts keys on hostname,
139 Returns a list of dicts
141 if not isinstance(slivers, list):
144 for sliver in slivers:
145 if isinstance(sliver, dict):
147 elif isinstance(sliver, basestring):
148 dicts.append({'hostname': sliver})
153 def toxml(self, cleanup=False):
156 return self.header + etree.tostring(self.xml, pretty_print=True)
158 def save(self, filename):
159 f = open(filename, 'w')
160 f.write(self.toxml())
163 if __name__ == '__main__':