Remove use of threads when retrieving layers

regulations/generator/generator.py

@@ -1,6 +1,5 @@
 import logging
 import re
-from threading import Thread
 
 from django.conf import settings
 
@@ -88,33 +87,17 @@ def add_layer(self, layer_name, regulation, version, sectional=False):
                 self.appliers[applier_type].add_layer(layer)
 
     def add_layers(self, layer_names, regulation, version, sectional=False):
-        """Request a list of layers. As this might spawn multiple HTTP
-        requests, we wrap the requests in threads so they can proceed
-        concurrently."""
+        """Request a list of layers."""
         #This doesn't deal with sectional interpretations yet.
         #we'll have to do that.
         layer_names = set(filter(lambda l: l.lower() in LayerCreator.LAYERS,
                                  layer_names))
-        results = []
-        procs = []
-
-        def one_layer(layer_name):
-            api_name, applier_type,\
-                layer_class = LayerCreator.LAYERS[layer_name]
-            layer_json = self.get_layer_json(api_name, regulation, version)
-            results.append((api_name, applier_type, layer_class, layer_json))
 
         #   Spawn threads
         for layer_name in layer_names:
-            proc = Thread(target=one_layer, args=(layer_name,))
-            procs.append(proc)
-            proc.start()
-
-        #   Join them (once their work is done)
-        for proc in procs:
-            proc.join()
-
-        for api_name, applier_type, layer_class, layer_json in results:
+            api_name, applier_type, layer_class = LayerCreator.LAYERS[layer_name]
+            layer_json = self.get_layer_json(api_name, regulation, version)
+
             if layer_json is None:
                 logging.warning("No data for %s/%s/%s"
                                 % (api_name, regulation, version))