AMQP 1.0 - create only one Cyrus SASL configuration for the tests

The Cyrus SASL library can only be initialized once per process. And
the configuration must remain available until all the tests have run.

Change-Id: I2810ecf53956fc5d4fcdc944f8e06237ca985e6a
Closes-Bug: #1591211

oslo_messaging/tests/drivers/test_amqp_driver.py

@@ -18,7 +18,6 @@ import select
 import shutil
 import socket
 import subprocess
-import tempfile
 import threading
 import time
 import uuid
@@ -378,58 +377,71 @@ class TestAuthentication(test_utils.BaseTestCase):
 class TestCyrusAuthentication(test_utils.BaseTestCase):
     """Test the driver's Cyrus SASL integration"""
 
-    def setUp(self):
+    _conf_dir = None
-        """Create a simple SASL configuration. This assumes saslpasswd2 is in
+
-        the OS path, otherwise the test will be skipped.
+    # Note: don't add ANONYMOUS or EXTERNAL mechs without updating the
-        """
+    # test_authentication_bad_mechs test below
-        super(TestCyrusAuthentication, self).setUp()
+    _mechs = "DIGEST-MD5 SCRAM-SHA-1 CRAM-MD5 PLAIN"
+
+    @classmethod
+    def setUpClass(cls):
+        # The Cyrus library can only be initialized once per _process_
         # Create a SASL configuration and user database,
         # add a user 'joe' with password 'secret':
-        self._conf_dir = tempfile.mkdtemp()
+        cls._conf_dir = "/tmp/amqp1_tests_%s" % os.getpid()
-        db = os.path.join(self._conf_dir, 'openstack.sasldb')
+        # no, we cannot use tempfile.mkdtemp() as it will 'helpfully' remove
+        # the temp dir after the first test is run (?why?)
+        os.makedirs(cls._conf_dir)
+        db = os.path.join(cls._conf_dir, 'openstack.sasldb')
         _t = "echo secret | saslpasswd2 -c -p -f ${db} joe"
         cmd = Template(_t).substitute(db=db)
         try:
             subprocess.check_call(args=cmd, shell=True)
         except Exception:
-            shutil.rmtree(self._conf_dir, ignore_errors=True)
+            shutil.rmtree(cls._conf_dir, ignore_errors=True)
-            self._conf_dir = None
+            cls._conf_dir = None
-            raise self.skip("Cyrus tool saslpasswd2 not installed")
+            return
 
-        # configure the SASL broker:
+        # configure the SASL server:
-        conf = os.path.join(self._conf_dir, 'openstack.conf')
+        conf = os.path.join(cls._conf_dir, 'openstack.conf')
-        # Note: don't add ANONYMOUS or EXTERNAL without updating the
-        # test_authentication_bad_mechs test below
-        mechs = "DIGEST-MD5 SCRAM-SHA-1 CRAM-MD5 PLAIN"
         t = Template("""sasldb_path: ${db}
 pwcheck_method: auxprop
 auxprop_plugin: sasldb
 mech_list: ${mechs}
 """)
         with open(conf, 'w') as f:
-            f.write(t.substitute(db=db, mechs=mechs))
+            f.write(t.substitute(db=db, mechs=cls._mechs))
 
-        self._broker = FakeBroker(sasl_mechanisms=mechs,
+    @classmethod
+    def tearDownClass(cls):
+        if cls._conf_dir:
+            shutil.rmtree(cls._conf_dir, ignore_errors=True)
+
+    def setUp(self):
+        # fire up a test broker with the SASL config:
+        super(TestCyrusAuthentication, self).setUp()
+        if TestCyrusAuthentication._conf_dir is None:
+            self.skipTest("Cyrus SASL tools not installed")
+        _mechs = TestCyrusAuthentication._mechs
+        _dir = TestCyrusAuthentication._conf_dir
+        self._broker = FakeBroker(sasl_mechanisms=_mechs,
                                   user_credentials=["\0joe\0secret"],
-                                  sasl_config_dir=self._conf_dir,
+                                  sasl_config_dir=_dir,
                                   sasl_config_name="openstack")
         self._broker.start()
         self.messaging_conf.transport_driver = 'amqp'
         self.conf = self.messaging_conf.conf
 
     def tearDown(self):
-        super(TestCyrusAuthentication, self).tearDown()
         if self._broker:
             self._broker.stop()
             self._broker = None
-        if self._conf_dir:
+        super(TestCyrusAuthentication, self).tearDown()
-            shutil.rmtree(self._conf_dir, ignore_errors=True)
 
     def test_authentication_ok(self):
         """Verify that username and password given in TransportHost are
         accepted by the broker.
         """
-
         addr = "amqp://joe:secret@%s:%d" % (self._broker.host,
                                             self._broker.port)
         url = oslo_messaging.TransportURL.parse(self.conf, addr)