Change arguments to postgres to use long flags

Make consistent with:
https://github.com/greenplum-db/gpdb/commit/d7e6e0ecac5c49d16c68fcb827a23b0116d07b5aSigned-off-by: NChumki Roy <croy@pivotal.io>
Signed-off-by: NC.J. Jameson <cjameson@pivotal.io>

gpMgmt/bin/gpexpand

@@ -2610,8 +2610,7 @@ class PrepFileSpaces(Command):
             entry = [filespaceNames[i] , filespaceLocations[i]]
             self.filespaces.append(entry)
         cmdStr  = """echo "select * from gp_prep_new_segment( array %s )" """ % (str(self.filespaces))
-        ###cmdStr += """ | $GPHOME/bin/postgres --single -z 1 -O -c gp_session_role=utility -c gp_debug_linger=0 -c gp_before_filespace_setup=true -c gp_before_persistence_work=true -E -D %s -b %s -C %s template1""" % (self.sysDataDirectory, str(self.dbid), str(self.contentId))
-        cmdStr += """ | $GPHOME/bin/postgres --single -z 1 -O -c gp_session_role=utility -c gp_debug_linger=0 -c gp_before_filespace_setup=true  -E -D %s -b %s -C %s template1""" % (self.sysDataDirectory, str(self.dbid), str(self.contentId))
+        cmdStr += """ | $GPHOME/bin/postgres --single --gp_num_contents_in_cluster=1 -O -c gp_session_role=utility -c gp_debug_linger=0 -c gp_before_filespace_setup=true  -E -D %s --gp_dbid=%s --gp_contentid=%s template1""" % (self.sysDataDirectory, str(self.dbid), str(self.contentId))
         Command.__init__(self,name,cmdStr,ctxt,remoteHost)
 
 
@@ -2989,15 +2988,18 @@ def sig_handler(sig, arg):
     os.kill(os.getpid(), sig)
 
 
-#------------------------------- Mainline --------------------------------
-gp_expand=None
-remove_pid=True
-table_expand_error=False
+# --------------------------------------------------------------------------
+# Main
+# --------------------------------------------------------------------------
+if __name__ == '__main__':
+    gp_expand=None
+    remove_pid=True
+    table_expand_error=False
 
-coverage = GpCoverage()
-coverage.start()
+    coverage = GpCoverage()
+    coverage.start()
 
-try:
+    try:
 
         # setup signal handlers so we can clean up correctly
         signal.signal(signal.SIGTERM, sig_handler)
@@ -3122,13 +3124,13 @@ try:
         logger.info("Exiting...")
         sys.exit(0)
 
-except ValidationError:
+    except ValidationError:
         logger.info('Bringing Greenplum Database back online...')
         if gp_expand is not None:
             gp_expand.shutdown()
         gpexpand.get_gpdb_in_state(GPDB_STARTED)
         sys.exit()
-except Exception,e:
+    except Exception,e:
         if options.verbose:
             logger.exception("gpexpand failed. exiting...")
         else:
@@ -3144,7 +3146,7 @@ except Exception,e:
                    logger.error('Please run \'gpexpand -r%s\' to rollback to the original state.' % ('' if not options.database else ' -D %s' % options.database))
             gp_expand.shutdown()
         sys.exit(3)
-except KeyboardInterrupt:
+    except KeyboardInterrupt:
         # Disable SIGINT while we shutdown.
         signal.signal(signal.SIGINT,signal.SIG_IGN)
 
@@ -3157,7 +3159,7 @@ except KeyboardInterrupt:
         sys.exit('\nUser Interrupted')
 
 
-finally:
+    finally:
         try:
             if remove_pid:
                 remove_pid_file(options.master_data_directory)

gpMgmt/bin/gppylib/test/unit/test_unit_gpexpand.py

+import os
+import imp
+
+from gp_unittest import *
+
+
+class GpExpand(GpTestCase):
+
+    def setUp(self):
+        # because gpexpand does not have a .py extension,
+        # we have to use imp to import it
+        # if we had a gpexpand.py, this is equivalent to:
+        #   import gpexpand
+        #   self.subject = gpexpand
+        gpexpand_file = os.path.abspath(os.path.dirname(__file__) + "/../../../gpexpand")
+        self.subject = imp.load_source('gpexpand', gpexpand_file)
+
+    def tearDown(self):
+        pass
+
+    def test_PrepFileSpaces_issues_correct_postgres_command(self):
+        prep_file_spaces = self.subject.PrepFileSpaces("name", [""], [""], "foo", 1, 1)
+
+        self.assertIn("--gp_contentid=", prep_file_spaces.cmdStr)
+        self.assertIn("--gp_num_contents_in_cluster=", prep_file_spaces.cmdStr)
+        self.assertIn("--gp_dbid=", prep_file_spaces.cmdStr)
+
+
+if __name__ == '__main__':
+    run_tests()