Add new parameter return_last_job_status to harvest_source_list

In order to get a quick overview over successful/failed harvesters, a
call to harvest_source_list with return_last_job_status=true can be used
to get this information.
By default return_last_job_status is False, and hence the extra
resources to grab this information is not wasted for every call, but
only if the client requests is explicitly.
The original 'status' field stays as-is, this PR introduces a new field
called 'last_job_status' to return this information.

The returned information is gather by a call to
harvest_source_status_show.

ckanext/harvest/logic/action/get.py

@@ -130,7 +130,9 @@ def harvest_source_list(context, data_dict):
 
     sources = _get_sources_for_user(context, data_dict)
 
-    return [harvest_source_dictize(source, context) for source in sources]
+    last_job_status = data_dict.get('return_last_job_status', False)
+
+    return [harvest_source_dictize(source, context, last_job_status) for source in sources]
 
 
 @side_effect_free

ckanext/harvest/logic/dictization.py

@@ -1,15 +1,12 @@
 from sqlalchemy import distinct, func
 
 from ckan.model import Package, Group
+from ckan import logic
 from ckanext.harvest.model import (HarvestSource, HarvestJob, HarvestObject,
                                    HarvestGatherError, HarvestObjectError)
 
 
-def harvest_source_dictize(source, context):
-    '''
-    TODO: Deprecated
-    '''
-
+def harvest_source_dictize(source, context, last_job_status=False):
     out = source.as_dict()
 
     out['publisher_title'] = u''
@@ -22,6 +19,10 @@ def harvest_source_dictize(source, context):
 
     out['status'] = _get_source_status(source, context)
 
+    if last_job_status:
+        source_status = logic.get_action('harvest_source_show_status')(context, {'id': source.id})
+        out['last_job_status'] = source_status.get('last_job', {})
+
     return out