Merge lp:~cjwatson/lazr.restful/double-closing-brace into lp:lazr.restful

[Colin Watson]

Fix double closing brace when encoding the result of a custom operation where the result has an adapter to ICollection.

Batch encoding is very weird; BatchingResourceMixin.batch intentionally omits the closing brace, and the caller is supposed to add it after possibly adding other parameters. This means that it's important for overridden implementations of the batch method in subclasses not to add the closing brace, as that violates the implied contract; only methods other than batch are allowed to add it. We were violating that rule in one code path, which resulted in a double closing brace.

This previously went unnoticed because of an overly-liberal doctest (which I had to fix anyway in order to cope with varying dict iteration order) and I think also because Launchpad tends to declare operations as having a return_type providing ICollectionField rather than directly returning something that can be adapted to ICollection.

[William Grant (wgrant)]

review: Approve (code)

=== modified file 'src/lazr/restful/NEWS.txt'
--- src/lazr/restful/NEWS.txt	2018-02-21 15:18:34 +0000
+++ src/lazr/restful/NEWS.txt	2018-09-28 15:11:57 +0000
@@ -2,6 +2,12 @@
 NEWS for lazr.restful
 =====================
 
+0.20.2
+======
+
+Fix double closing brace when encoding the result of a custom operation
+where the result has an adapter to ICollection.
+
 0.20.1 (2018-02-21)
 ===================
 
 
=== modified file 'src/lazr/restful/_resource.py'
--- src/lazr/restful/_resource.py	2016-02-17 01:07:21 +0000
+++ src/lazr/restful/_resource.py	2018-09-28 15:11:57 +0000
@@ -1801,7 +1801,7 @@
                 self.request.response.setHeader('Content-Type', media_type)
                 return result
 
-            result = self.batch(entries)
+            result = self.batch(entries) + '}'
 
         self.request.response.setHeader('Content-type', self.JSON_TYPE)
         return result
@@ -1818,8 +1818,7 @@
             request = self.request
         result = super(CollectionResource, self).batch(entries, request)
         result += (
-            ', "resource_type_link" : ' + simplejson.dumps(self.type_url)
-            + '}')
+            ', "resource_type_link" : ' + simplejson.dumps(self.type_url))
         return result
 
     @property
 
=== modified file 'src/lazr/restful/docs/webservice.txt'
--- src/lazr/restful/docs/webservice.txt	2016-02-17 01:07:21 +0000
+++ src/lazr/restful/docs/webservice.txt	2018-09-28 15:11:57 +0000
@@ -1585,8 +1585,12 @@
 batch from the collection.
 
     >>> request, operation = make_dummy_operation_request(DishSet())
-    >>> operation()
-    '{"total_size": ..., "start": ...}'
+    >>> response = operation()
+    >>> for key, value in sorted(simplejson.loads(response).items()):
+    ...     print '%s: %s' % (key, value)
+    entries: ...
+    start: ...
+    total_size: ...
 
 If the return value can't be converted into JSON, you'll get an
 exception.