friends/rd/xrd.py

   1
   2 from xml.dom.minidom import getDOMImplementation, parseString, Node
   3
   4 from rd.core import RD, Element, Link, Property, Title
   5
   6 XRD_NAMESPACE = "http://docs.oasis-open.org/ns/xri/xrd-1.0"
   7
   8
   9 def _get_text(root):
  10     text = ''
  11     for node in root.childNodes:
  12         if node.nodeType == Node.TEXT_NODE and node.nodeValue:
  13             text += node.nodeValue
  14         else:
  15             text += _get_text(node)
  16     return text.strip() or None
  17
  18
  19 def loads(content):
  20
  21     import isodate
  22
  23     def expires_handler(node, obj):
  24         obj.expires = isodate.parse_datetime(_get_text(node))
  25
  26     def subject_handler(node, obj):
  27         obj.subject = _get_text(node)
  28
  29     def alias_handler(node, obj):
  30         obj.aliases.append(_get_text(node))
  31
  32     def property_handler(node, obj):
  33         obj.properties.append(Property(node.getAttribute('type'), _get_text(node)))
  34
  35     def title_handler(node, obj):
  36         obj.titles.append(Title(_get_text(node), node.getAttribute('xml:lang')))
  37
  38     def link_handler(node, obj):
  39         l = Link()
  40         l.rel = node.getAttribute('rel')
  41         l.type = node.getAttribute('type')
  42         l.href = node.getAttribute('href')
  43         l.template = node.getAttribute('template')
  44         obj.links.append(l)
  45
  46     handlers = {
  47         'Expires': expires_handler,
  48         'Subject': subject_handler,
  49         'Alias': alias_handler,
  50         'Property': property_handler,
  51         'Link': link_handler,
  52         'Title': title_handler,
  53     }
  54
  55     def unknown_handler(node, obj):
  56         obj.elements.append(Element(
  57             name=node.tagName,
  58             value=_get_text(node),
  59         ))
  60
  61     def handle_node(node, obj):
  62         handler = handlers.get(node.nodeName, unknown_handler)
  63         if handler and node.nodeType == node.ELEMENT_NODE:
  64             handler(node, obj)
  65
  66     doc = parseString(content)
  67     root = doc.documentElement
  68
  69     rd = RD(root.getAttribute('xml:id'))
  70
  71     for name, value in list(root.attributes.items()):
  72         if name != 'xml:id':
  73             rd.attributes.append((name, value))
  74
  75     for node in root.childNodes:
  76         handle_node(node, rd)
  77         if node.nodeName == 'Link':
  78             link = rd.links[-1]
  79             for child in node.childNodes:
  80                 handle_node(child, link)
  81
  82     return rd
  83
  84
  85 def dumps(xrd):
  86
  87     doc = getDOMImplementation().createDocument(XRD_NAMESPACE, "XRD", None)
  88     root = doc.documentElement
  89     root.setAttribute('xmlns', XRD_NAMESPACE)
  90
  91     if xrd.xml_id:
  92         root.setAttribute('xml:id', xrd.xml_id)
  93
  94     for attr in xrd.attributes:
  95         root.setAttribute(attr.name, attr.value)
  96
  97     if xrd.expires:
  98         node = doc.createElement('Expires')
  99         node.appendChild(doc.createTextNode(xrd.expires.isoformat()))
 100         root.appendChild(node)
 101
 102     if xrd.subject:
 103         node = doc.createElement('Subject')
 104         node.appendChild(doc.createTextNode(xrd.subject))
 105         root.appendChild(node)
 106
 107     for alias in xrd.aliases:
 108         node = doc.createElement('Alias')
 109         node.appendChild(doc.createTextNode(alias))
 110         root.appendChild(node)
 111
 112     for prop in xrd.properties:
 113         node = doc.createElement('Property')
 114         node.setAttribute('type', prop.type)
 115         if prop.value:
 116             node.appendChild(doc.createTextNode(str(prop.value)))
 117         else:
 118             node.setAttribute('xsi:nil', 'true')
 119         root.appendChild(node)
 120
 121     for element in xrd.elements:
 122         node = doc.createElement(element.name)
 123         node.appendChild(doc.createTextNode(element.value))
 124         root.appendChild(node)
 125
 126     for link in xrd.links:
 127
 128         if link.href and link.template:
 129             raise ValueError('only one of href or template attributes may be specified')
 130
 131         link_node = doc.createElement('Link')
 132
 133         if link.rel:
 134             link_node.setAttribute('rel', link.rel)
 135
 136         if link.type:
 137             link_node.setAttribute('type', link.type)
 138
 139         if link.href:
 140             link_node.setAttribute('href', link.href)
 141
 142         if link.template:
 143             link_node.setAttribute('template', link.template)
 144
 145         for title in link.titles:
 146             node = doc.createElement('Title')
 147             node.appendChild(doc.createTextNode(str(title)))
 148             if title.lang:
 149                 node.setAttribute('xml:lang', title.lang)
 150             link_node.appendChild(node)
 151
 152         for prop in link.properties:
 153             node = doc.createElement('Property')
 154             node.setAttribute('type', prop.type)
 155             if prop.value:
 156                 node.appendChild(doc.createTextNode(str(prop.value)))
 157             else:
 158                 node.setAttribute('xsi:nil', 'true')
 159             link_node.appendChild(node)
 160
 161         root.appendChild(link_node)
 162
 163     return doc