Merge branch 'ldapper'

Conflicts:
	Dockerfile
	app.py
	data/database.py
	endpoints/index.py
	test/data/test.db

util/validation.py

@@ -1,7 +1,16 @@
 import re
+import string
+
+from unidecode import unidecode
+
 
 INVALID_PASSWORD_MESSAGE = 'Invalid password, password must be at least ' + \
                            '8 characters and contain no whitespace.'
+INVALID_USERNAME_CHARACTERS = r'[^a-z0-9_]'
+VALID_CHARACTERS = '_' + string.digits + string.lowercase
+MIN_LENGTH = 4
+MAX_LENGTH = 30
+
 
 def validate_email(email_address):
   if re.match(r'[^@]+@[^@]+\.[^@]+', email_address):
@@ -11,13 +20,14 @@ def validate_email(email_address):
 
 def validate_username(username):
   # Based off the restrictions defined in the Docker Registry API spec
-  regex_match = (re.search(r'[^a-z0-9_]', username) is None)
+  regex_match = (re.search(INVALID_USERNAME_CHARACTERS, username) is None)
   if not regex_match:
     return (False, 'Username must match expression [a-z0-9_]+')
 
-  length_match = (len(username) >= 4 and len(username) <= 30)
+  length_match = (len(username) >= MIN_LENGTH and len(username) <= MAX_LENGTH)
   if not length_match:
-    return (False, 'Username must be between 4 and 30 characters in length')
+    return (False, 'Username must be between %s and %s characters in length' %
+            (MIN_LENGTH, MAX_LENGTH))
 
   return (True, '')
 
@@ -27,3 +37,24 @@ def validate_password(password):
   if re.search(r'\s', password):
     return False
   return len(password) > 7
+
+
+def _gen_filler_chars(num_filler_chars):
+  if num_filler_chars == 0:
+    yield ''
+  else:
+    for char in VALID_CHARACTERS:
+      for suffix in _gen_filler_chars(num_filler_chars - 1):
+        yield char + suffix
+
+
+def generate_valid_usernames(input_username):
+  normalized = unidecode(input_username).strip().lower()
+  prefix = re.sub(INVALID_USERNAME_CHARACTERS, '_', normalized)[:30]
+
+  num_filler_chars = max(0, MIN_LENGTH - len(prefix))
+
+  while num_filler_chars + len(prefix) <= MAX_LENGTH:
+    for suffix in _gen_filler_chars(num_filler_chars):
+      yield prefix + suffix
+    num_filler_chars += 1