Randomize the diffs a little bit better.

initdb.py

@@ -4,7 +4,7 @@ import shutil
 import os
 import hashlib
 
-from datetime import datetime
+from datetime import datetime, timedelta
 
 import storage
 
@@ -24,41 +24,45 @@ SAMPLE_DIFFS = [
   'test/data/sample/diffs/diffs3.json',
 ]
 
+REFERENCE_DATE = datetime(2013, 6, 23)
+
 
 def __gen_checksum(image_id):
   h = hashlib.md5(image_id)
   return 'tarsum+sha256:' + h.hexdigest()
 
 
-global_image_num = [0]
-def __gen_image_id(repo):
-  str_to_hash = "%s/%s/%s" % (repo.namespace, repo.name, global_image_num[0])
-  global_image_num[0] += 1
+def __gen_image_id(repo, image_num):
+  str_to_hash = "%s/%s/%s" % (repo.namespace, repo.name, image_num)
 
   h = hashlib.md5(str_to_hash)
   return h.hexdigest()
 
 
+global_image_num = [0]
 def create_subtree(repo, structure, parent):
   num_nodes, subtrees, last_node_tags = structure
 
   # create the nodes
   for i in range(num_nodes):
-    docker_image_id = __gen_image_id(repo)
+    image_num = global_image_num[0]
+    global_image_num[0] += 1
+    docker_image_id = __gen_image_id(repo, image_num)
     logger.debug('new docker id: %s' % docker_image_id)
     checksum = __gen_checksum(docker_image_id)
 
     new_image = model.create_image(docker_image_id, repo)
     model.set_image_checksum(docker_image_id, repo, checksum)
 
+    creation_time = REFERENCE_DATE + timedelta(days=image_num)
     new_image = model.set_image_metadata(docker_image_id, repo.namespace,
-                                         repo.name, str(datetime.now()),
+                                         repo.name, str(creation_time),
                                          'no comment', parent)
 
     # Populate the diff file
     diff_path = store.image_file_diffs_path(repo.namespace, repo.name,
-                                          docker_image_id)
-    source_diff = SAMPLE_DIFFS[i % len(SAMPLE_DIFFS)]
+                                            docker_image_id)
+    source_diff = SAMPLE_DIFFS[image_num % len(SAMPLE_DIFFS)]
 
     with open(source_diff, 'r') as source_file:
       store.stream_write(diff_path, source_file)