[#97] Persitent endpoint for datasets harvest objects

Contrary to `/harvest/object/xxx`, this endpoint is passed the dataset
id, thus it not depends on a particular object but the most recent one.

ckanext/harvest/controllers/view.py

@@ -88,11 +88,14 @@ class ViewController(BaseController):
 
         redirect(h.url_for('{0}_admin'.format(DATASET_TYPE_NAME), id=id))
 
-    def show_object(self,id):
+    def show_object(self, id, ref_type='object'):
 
         try:
             context = {'model':model, 'user':c.user}
-            obj = p.toolkit.get_action('harvest_object_show')(context, {'id':id})
+            if ref_type == 'object':
+                obj = p.toolkit.get_action('harvest_object_show')(context, {'id': id})
+            elif ref_type == 'dataset':
+                obj = p.toolkit.get_action('harvest_object_show')(context, {'dataset_id': id})
 
             # Check content type. It will probably be either XML or JSON
             try:
@@ -119,8 +122,8 @@ class ViewController(BaseController):
 
             response.headers['Content-Length'] = len(content)
             return content.encode('utf-8')
-        except p.toolkit.ObjectNotFound:
-            abort(404,_('Harvest object not found'))
+        except p.toolkit.ObjectNotFound, e:
+            abort(404,_(str(e)))
         except p.toolkit.NotAuthorized:
             abort(401,self.not_auth_message)
         except Exception, e:

ckanext/harvest/logic/action/get.py

@@ -249,15 +249,34 @@ def harvest_job_list(context,data_dict):
 @side_effect_free
 def harvest_object_show(context,data_dict):
 
-    check_access('harvest_object_show',context,data_dict)
+    p.toolkit.check_access('harvest_object_show', context, data_dict)
 
     id = data_dict.get('id')
-    attr = data_dict.get('attr',None)
-    obj = HarvestObject.get(id,attr=attr)
-    if not obj:
-        raise NotFound
+    dataset_id = data_dict.get('dataset_id')
 
-    return harvest_object_dictize(obj,context)
+    if id:
+        attr = data_dict.get('attr',None)
+        obj = HarvestObject.get(id,attr=attr)
+    elif dataset_id:
+        model = context['model']
+
+        pkg = model.Package.get(dataset_id)
+        if not pkg:
+            raise p.toolkit.ObjectNotFound('Dataset not found')
+
+        obj = model.Session.query(HarvestObject) \
+              .filter(HarvestObject.package_id == pkg.id) \
+              .filter(HarvestObject.current == True) \
+              .first()
+    else:
+        raise p.toolkit.ValidationError(
+            'Please provide either an "id" or a "dataset_id" parameter')
+
+    if not obj:
+        raise p.toolkit.ObjectNotFound('Harvest object not found')
+
+
+    return harvest_object_dictize(obj, context)
 
 @side_effect_free
 def harvest_object_list(context,data_dict):

ckanext/harvest/plugin.py

@@ -210,6 +210,7 @@ class Harvest(p.SingletonPlugin, DefaultDatasetForm):
         map.connect('harvest_job_show', '/' + DATASET_TYPE_NAME + '/{source}/job/{id}', controller=controller, action='show_job')
 
         map.connect('harvest_object_show', '/' + DATASET_TYPE_NAME + '/object/:id', controller=controller, action='show_object')
+        map.connect('harvest_object_for_dataset_show', '/dataset/harvest_object/:id', controller=controller, action='show_object', ref_type='dataset')
 
         org_controller = 'ckanext.harvest.controllers.organization:OrganizationController'
         map.connect('{0}_org_list'.format(DATASET_TYPE_NAME), '/organization/' + DATASET_TYPE_NAME + '/' + '{id}', controller=org_controller, action='source_list')