Merge branch 'upstreammaster'
[sfa.git] / sfa / rspecs / elements / element.py
1 class Element(dict):
2
3     fields = {}
4
5     def __init__(self, fields={}, element=None, keys=None):
6         self.element = element
7         dict.__init__(self, dict.fromkeys(self.fields))
8         if not keys:
9             keys = fields.keys()
10         for key in keys:
11             if key in fields:
12                 self[key] = fields[key] 
13
14     @staticmethod
15     def get_elements(xml, xpath, element_class=None, fields=None):
16         """
17         Search the specifed xml node for elements that match the 
18         specified xpath query. 
19         Returns a list of objects instanced by the specified element_class.
20         """
21         if not element_class:
22             element_class = Element
23         if not fields and hasattr(element_class, 'fields'):
24            fields = element_class.fields
25         elems = xml.xpath(xpath)
26         objs = []
27         for elem in elems:
28             if not fields:
29                 obj = element_class(elem.attrib, elem)
30             else:
31                 obj = element_class({}, elem)
32                 for field in fields:
33                     if field in elem.attrib:
34                         obj[field] = elem.attrib[field]    
35             objs.append(obj)
36         return objs
37
38     @staticmethod
39     def add_elements(xml, name, objs, fields=None):
40         """
41         Adds a child node to the specified xml node based on
42         the specified name , element class and object.    
43         """
44         if not isinstance(objs, list):
45             objs = [objs]
46         elems = []
47         for obj in objs:
48             if not obj:
49                 continue
50             if not fields:
51                 fields = obj.keys()
52             elem = xml.add_element(name)
53             for field in fields:
54                 if field in obj and obj[field]:
55                     elem.set(field, unicode(obj[field]))
56             elems.append(elem)
57         return elems