Use 0001-01-01 as a placeholder for None publication, amendment and repeal dates

README.rst

@@ -92,6 +92,7 @@ Change Log
 - Cascade changes to FRBRlanguage into attachments
 - Don't hardcode source
 - Don't set ``contains="originalVersion"`` since it is the default value for that attribute.
+- Use ``0001-01-01`` as a placeholder date for publication, amendment and repeal events with null dates
 
 4.1.1
 .....

cobalt/akn.py

@@ -25,16 +25,29 @@
 }
 DEFAULT_VERSION = '3.0'
 
+# a placeholder date that indicates a null date, used in the XML where a date is required by may not be known
+NULL_DATE = '0001-01-01'
+
 
 def datestring(value):
+    """ Format a date as an XML-suitable string. If the date is None, uses NULL_DATE.
+    """
     if value is None:
-        return ""
+        return NULL_DATE
     elif isinstance(value, str):
         return value
     else:
         return "%04d-%02d-%02d" % (value.year, value.month, value.day)
 
 
+def parsedate(value):
+    """ Parse an XML date string into a real date. If the value is the NULL_DATE, returns None.
+    """
+    if value == NULL_DATE:
+        return None
+    return parse_date(value).date()
+
+
 # Create a new objectify parser that doesn't remove blank text nodes
 objectify_parser = etree.XMLParser()
 objectify_parser.set_element_class_lookup(objectify.ObjectifyElementClassLookup())
@@ -91,7 +104,7 @@ def get_namespace(self):
 
         raise ValueError(f"Expected to find one of the following Akoma Ntoso XML namespaces: {', '.join(akn_namespaces)}. Only these namespaces were found: {', '.join(namespaces)}")
 
-    def ensure_element(self, name, after, at=None):
+    def ensure_element(self, name, after, at=None, attribs=None):
         """ Helper to get an element if it exists, or create it if it doesn't.
 
         :param name: dotted path from `self` or `at`
@@ -101,7 +114,7 @@ def ensure_element(self, name, after, at=None):
         node = self.get_element(name, root=at)
         if node is None:
             # TODO: what if nodes in the path don't exist?
-            node = self.make_element(name.split('.')[-1])
+            node = self.make_element(name.split('.')[-1], attribs)
             after.addnext(node)
 
         return node
@@ -123,8 +136,9 @@ def get_element(self, name, root=None):
                 return None
         return node
 
-    def make_element(self, elem):
-        return getattr(self.maker, elem)()
+    def make_element(self, elem, attribs=None):
+        attribs = attribs or {}
+        return getattr(self.maker, elem)(**attribs)
 
 
 class StructuredDocument(AkomaNtosoDocument):

cobalt/hierarchical.py

@@ -1,6 +1,4 @@
-from iso8601 import parse_date
-
-from .akn import StructuredDocument, datestring
+from .akn import StructuredDocument, datestring, NULL_DATE, parsedate
 
 
 class HierarchicalStructure(StructuredDocument):
@@ -33,7 +31,7 @@ def publication_name(self):
     @publication_name.setter
     def publication_name(self, value):
         value = value or ""
-        pub = self.ensure_element('meta.publication', after=self.meta.identification)
+        pub = self.ensure_publication()
         pub.set('name', value)
         pub.set('showAs', value)
 
@@ -43,13 +41,12 @@ def publication_date(self):
         """
         pub = self.get_element('meta.publication')
         if pub is not None and pub.get('date'):
-            return parse_date(pub.get('date')).date()
+            return parsedate(pub.get('date'))
         return None
 
     @publication_date.setter
     def publication_date(self, value):
-        self.ensure_element('meta.publication', after=self.meta.identification)\
-            .set('date', datestring(value))
+        self.ensure_publication().set('date', datestring(value))
 
     @property
     def publication_number(self):
@@ -60,15 +57,14 @@ def publication_number(self):
 
     @publication_number.setter
     def publication_number(self, value):
-        self.ensure_element('meta.publication', after=self.meta.identification)\
-            .set('number', value or "")
+        self.ensure_publication().set('number', value or "")
 
     @property
     def amendments(self):
         amendments = []
 
         for e in self.meta.iterfind(f'.//{{{self.namespace}}}lifecycle/{{{self.namespace}}}eventRef[@type="amendment"]'):
-            date = parse_date(e.get('date')).date()
+            date = parsedate(e.get('date'))
             event = AmendmentEvent(date=date)
             amendments.append(event)
 
@@ -132,7 +128,7 @@ def amendments(self, value):
     def repeal(self):
         e = self.meta.find(f'.//{{{self.namespace}}}lifecycle/{{{self.namespace}}}eventRef[@type="repeal"]')
         if e is not None:
-            date = parse_date(e.get('date')).date()
+            date = parsedate(e.get('date'))
             event = RepealEvent(date=date)
 
             id = e.get('source')[1:]
@@ -183,6 +179,10 @@ def repeal(self, value):
             except AttributeError:
                 pass
 
+    def ensure_publication(self):
+        return self.ensure_element('meta.publication', after=self.meta.identification,
+                                   attribs={'showAs': '', 'name': '', 'date': NULL_DATE})
+
 
 class AmendmentEvent(object):
     """ An event that amended a document.

tests/test_act.py

@@ -22,33 +22,43 @@ def test_empty_act(self):
     def test_empty_body(self):
         a = Act()
         assert_not_equal(a.body.text, '')
+        assert_validates(a)
 
     def test_publication_date(self):
         a = Act()
         assert_is_none(a.publication_date)
+        assert_validates(a)
 
         a.publication_date = '2012-01-02'
         assert_equal(datestring(a.publication_date), '2012-01-02')
         assert_is_instance(a.publication_date, date)
+        assert_validates(a)
+
+        a.publication_date = None
+        assert_is_none(a.publication_date)
+        assert_validates(a)
 
     def test_publication_number(self):
         a = Act()
         assert_is_none(a.publication_number)
 
         a.publication_number = '1234'
         assert_equal(a.publication_number, '1234')
+        assert_validates(a)
 
     def test_publication_name(self):
         a = Act()
         assert_is_none(a.publication_name)
 
         a.publication_name = 'Publication'
         assert_equal(a.publication_name, 'Publication')
+        assert_validates(a)
 
     def test_set_amendments(self):
         a = Act()
         a.frbr_uri = "/akn/za/act/1900/1"
         a.amendments = [AmendmentEvent(date='2012-02-01', amending_uri='/za/act/1980/10', amending_title="Foo")]
+        assert_validates(a)
 
         xml = a.to_xml(encoding='unicode', pretty_print=True)
         xml = xml.replace(datestring(date.today()), 'TODAY')
@@ -104,6 +114,7 @@ def test_set_amendments(self):
             AmendmentEvent(date='2012-02-01', amending_uri='/za/act/1980/22', amending_title="Corrected"),
             AmendmentEvent(date='2013-03-03', amending_uri='/za/act/1990/5', amending_title="Bar"),
         ]
+        assert_validates(a)
 
         xml = a.to_xml(encoding='unicode', pretty_print=True)
         xml = xml.replace(datestring(date.today()), 'TODAY')
@@ -171,6 +182,7 @@ def test_set_amendments(self):
 
         # clear them
         a.amendments = []
+        assert_validates(a)
         xml = a.to_xml(encoding='unicode', pretty_print=True)
         xml = xml.replace(datestring(date.today()), 'TODAY')