Merge lp:~cjwatson/lazr.restful/datetime-unmarshall into lp:lazr.restful

[Colin Watson]

Implement DateTimeFieldMarshaller.unmarshall.

This is cleaner than special-casing `date` and `datetime` objects in `ResourceJSONEncoder.default`.

[Ioana Lasc (ilasc)]

review: Approve

[Cristian Gonzalez (cristiangsp)]

Looks good!

review: Approve

=== modified file 'NEWS.rst'
--- NEWS.rst	2021-05-14 12:46:54 +0000
+++ NEWS.rst	2021-05-18 15:16:23 +0000
@@ -2,6 +2,12 @@
 NEWS for lazr.restful
 =====================
 
+1.0.3
+=====
+
+Give ``DateTimeFieldMarshaller`` an ``unmarshall`` method, rather than
+special-casing it elsewhere.
+
 1.0.2 (2021-05-14)
 ==================
 
 
=== modified file 'src/lazr/restful/_resource.py'
--- src/lazr/restful/_resource.py	2021-05-14 09:10:28 +0000
+++ src/lazr/restful/_resource.py	2021-05-18 15:16:23 +0000
@@ -29,8 +29,6 @@
     'WADL_SCHEMA_FILE',
     ]
 
-
-from datetime import datetime, date
 from email.utils import formatdate
 import copy
 from operator import itemgetter
@@ -222,8 +220,6 @@
 
     def default(self, obj):
         """Convert the given object to a simple data structure."""
-        if isinstance(obj, datetime) or isinstance(obj, date):
-            return obj.isoformat()
         if isProxy(obj):
             # We have a security-proxied version of a built-in
             # type. We create a new version of the type by copying the
 
=== modified file 'src/lazr/restful/docs/webservice-marshallers.rst'
--- src/lazr/restful/docs/webservice-marshallers.rst	2021-01-21 11:42:18 +0000
+++ src/lazr/restful/docs/webservice-marshallers.rst	2021-05-18 15:16:23 +0000
@@ -385,6 +385,12 @@
       ...
     ValueError: Value doesn't look like a date.
 
+The unmarshall() method returns the ISO 8601 representation of the value.
+
+    >>> marshaller.unmarshall(
+    ...     None, marshaller.marshall_from_json_data('2009-07-07T13:45:00Z'))
+    '2009-07-07T13:45:00+00:00'
+
 Date
 ----
 
@@ -406,6 +412,12 @@
     >>> marshaller.marshall_from_json_data('2009-07-07T13:15:00+0000')
     datetime.date(2009, 7, 7)
 
+The unmarshall() method returns the ISO 8601 representation of the value.
+
+    >>> marshaller.unmarshall(
+    ...     None, marshaller.marshall_from_json_data('2009-07-09'))
+    '2009-07-09'
+
 Text
 ----
 
 
=== modified file 'src/lazr/restful/marshallers.py'
--- src/lazr/restful/marshallers.py	2021-01-21 11:42:18 +0000
+++ src/lazr/restful/marshallers.py	2021-05-18 15:16:23 +0000
@@ -409,6 +409,13 @@
             # JSON will serialize '20090131' as a number
             raise ValueError("Value doesn't look like a date.")
 
+    def unmarshall(self, entry, value):
+        """See `IFieldMarshaller`.
+
+        Represent the datetime in ISO 8601 format.
+        """
+        return None if value is None else value.isoformat()
+
 
 class DateFieldMarshaller(DateTimeFieldMarshaller):
     """A marshaller that transforms its value into a date object."""