adds decorators to reduce boilerplate code

src/py/crankshaft/crankshaft/analysis_data_provider.py

@@ -6,56 +6,45 @@ NULL_VALUE_ERROR = ('No usable data passed to analysis. Check your input rows '
                     'for null values and fill in appropriately.')
 
 
-def verify_data(data):
-    if len(data) == 0:
-        plpy.error(NULL_VALUE_ERROR)
+def verify_data(f):
+    def wrapper(*args, **kwargs):
+        try:
+            print('kwargs: %s' % str(kwargs))
+            data = f(*args, **kwargs)
+            if len(data) == 0:
+                plpy.error(NULL_VALUE_ERROR)
+            else:
+                return data
+        except Exception, err:
+            plpy.error('Analysis failed: {}'.format(err))
+    return wrapper
 
 
 class AnalysisDataProvider(object):
+    @verify_data
     def get_getis(self, w_type, params):
         """fetch data for getis ord's g"""
-        try:
-            query = pu.construct_neighbor_query(w_type, params)
-            data = plpy.execute(query)
-
-            # if there are no neighbors or all nulls, exit
-            verify_data(data)
-            return data
-        except plpy.SPIError, err:
-            plpy.error('Analysis failed: %s' % err)
+        query = pu.construct_neighbor_query(w_type, params)
+        return plpy.execute(query)
 
+    @verify_data
     def get_markov(self, w_type, params):
         """fetch data for spatial markov"""
-        try:
-            query = pu.construct_neighbor_query(w_type, params)
-            data = plpy.execute(query)
-
-            verify_data(data)
-            return data
-        except plpy.SPIError, err:
-            plpy.error('Analysis failed: %s' % err)
+        query = pu.construct_neighbor_query(w_type, params)
+        return plpy.execute(query)
 
+    @verify_data
     def get_moran(self, w_type, params):
         """fetch data for moran's i analyses"""
-        try:
-            query = pu.construct_neighbor_query(w_type, params)
-            data = plpy.execute(query)
-
-            # if there are no neighbors, exit
-            verify_data(data)
-            return data
-        except plpy.SPIError, err:
-            plpy.error('Analysis failed: %s' % err)
+        query = pu.construct_neighbor_query(w_type, params)
+        return plpy.execute(query)
 
+    @verify_data
     def get_nonspatial_kmeans(self, query):
         """fetch data for non-spatial kmeans"""
-        try:
-            data = plpy.execute(query)
-            verify_data(data)
-            return data
-        except plpy.SPIError, err:
-            plpy.error('Analysis failed: %s' % err)
+        return plpy.execute(query)
 
+    @verify_data
     def get_spatial_kmeans(self, params):
         """fetch data for spatial kmeans"""
         query = '''
@@ -66,9 +55,5 @@ class AnalysisDataProvider(object):
                 FROM ({subquery}) As a
                 WHERE "{geom_col}" IS NOT NULL
                 '''.format(**params)
-        try:
-            data = plpy.execute(query)
-            verify_data(data)
-            return data
-        except plpy.SPIError, err:
-            plpy.error('Analysis failed: %s' % err)
+
+        return plpy.execute(query)