Add function for generating UUIDs in the Haskell codebase

Its first use will be to generate the salt for ConfD requests of the Haskell
client, as in the Python client.

Unit test added as well.

Signed-off-by: Michele Tartara <mtartara@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

diff --git a/htest/Test/Ganeti/Utils.hs b/htest/Test/Ganeti/Utils.hs
index 461d1b2..cb357a1 100644 (file)
--- a/htest/Test/Ganeti/Utils.hs
+++ b/htest/Test/Ganeti/Utils.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TemplateHaskell, CPP #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 {-| Unittests for ganeti-htools.
@@ -34,11 +34,15 @@ import Test.HUnit
 import Data.Char (isSpace)
 import Data.List
 import qualified Text.JSON as J
+#ifndef NO_REGEX_PCRE
+import Text.Regex.PCRE
+#endif
 
 import Test.Ganeti.TestHelper
 import Test.Ganeti.TestCommon
 
 import Ganeti.BasicTypes
+import qualified Ganeti.Constants as C
 import qualified Ganeti.JSON as JSON
 import Ganeti.Utils
 
@@ -219,6 +223,14 @@ prop_rStripSpace (NonEmpty str) =
               rStripSpace "" ==? ""
           ]
 
+#ifndef NO_REGEX_PCRE
+-- | Tests that the newUUID function produces valid UUIDs.
+case_new_uuid :: Assertion
+case_new_uuid = do
+  uuid <- newUUID
+  assertBool "newUUID" $ uuid =~ C.uuidRegex
+#endif
+
 -- | Test list for the Utils module.
 testSuite "Utils"
             [ 'prop_commaJoinSplit
@@ -235,4 +247,7 @@ testSuite "Utils"
             , 'prop_niceSort_numbers
             , 'prop_niceSortKey_equiv
             , 'prop_rStripSpace
+#ifndef NO_REGEX_PCRE
+            , 'case_new_uuid
+#endif
             ]

diff --git a/htools/Ganeti/Utils.hs b/htools/Ganeti/Utils.hs
index 9f7e9c5..eed65dd 100644 (file)
--- a/htools/Ganeti/Utils.hs
+++ b/htools/Ganeti/Utils.hs
@@ -44,6 +44,7 @@ module Ganeti.Utils
   , exitWhen
   , exitUnless
   , rStripSpace
+  , newUUID
   ) where
 
 import Data.Char (toUpper, isAlphaNum, isDigit, isSpace)
@@ -53,6 +54,7 @@ import Data.List
 import Debug.Trace
 
 import Ganeti.BasicTypes
+import qualified Ganeti.Constants as C
 import System.IO
 import System.Exit
 
@@ -277,3 +279,11 @@ niceSortKey keyfn =
 -- expensive, should only be run on small strings.
 rStripSpace :: String -> String
 rStripSpace = reverse . dropWhile isSpace . reverse
+
+-- | Returns a random UUID.
+-- This is a Linux-specific method as it uses the /proc filesystem.
+newUUID :: IO String
+newUUID = do
+  contents <- readFile C.randomUuidFile
+  let stripNewlines = reverse . dropWhile (=='\n') . reverse
+  return $! stripNewlines $ take 128 contents

diff --git a/lib/constants.py b/lib/constants.py
index 900b4bc..2d106f1 100644 (file)
--- a/lib/constants.py
+++ b/lib/constants.py
@@ -2210,5 +2210,11 @@ NDS_NODE_DAEMON_CERTIFICATE = "node_daemon_certificate"
 NDS_SSCONF = "ssconf"
 NDS_START_NODE_DAEMON = "start_node_daemon"
 
+# Path generating random UUID
+RANDOM_UUID_FILE = "/proc/sys/kernel/random/uuid"
+
+# Regex string for verifying a UUID
+UUID_REGEX = "^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$"
+
 # Do not re-export imported modules
 del re, _vcsversion, _autoconf, socket, pathutils, compat

diff --git a/lib/utils/__init__.py b/lib/utils/__init__.py
index ab7225f..69cc0a3 100644 (file)
--- a/lib/utils/__init__.py
+++ b/lib/utils/__init__.py
@@ -59,8 +59,7 @@ from ganeti.utils.x509 import *
 
 _VALID_SERVICE_NAME_RE = re.compile("^[-_.a-zA-Z0-9]{1,128}$")
 
-UUID_RE = re.compile("^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-"
-                     "[a-f0-9]{4}-[a-f0-9]{12}$")
+UUID_RE = re.compile(constants.UUID_REGEX)
 
 
 def ForceDictType(target, key_types, allowed_values=None):

diff --git a/lib/utils/io.py b/lib/utils/io.py
index bb0a123..f9675a8 100644 (file)
--- a/lib/utils/io.py
+++ b/lib/utils/io.py
@@ -35,10 +35,6 @@ from ganeti import constants
 from ganeti import pathutils
 from ganeti.utils import filelock
 
-
-#: Path generating random UUID
-_RANDOM_UUID_FILE = "/proc/sys/kernel/random/uuid"
-
 #: Directory used by fsck(8) to store recovered data, usually at a file
 #: system's root directory
 _LOST_AND_FOUND = "lost+found"
@@ -1029,7 +1025,7 @@ def NewUUID():
   @rtype: str
 
   """
-  return ReadFile(_RANDOM_UUID_FILE, size=128).rstrip("\n")
+  return ReadFile(constants.RANDOM_UUID_FILE, size=128).rstrip("\n")
 
 
 class TemporaryFileManager(object):