Use manual zkhandler creation in Benchmark job

Like the other Celery job this does not work properly with the
ZKConnection decorator due to conflicting "self", so just connect
manually exactly like the provisioner task does.

api-daemon/pvcapid/benchmark.py

@@ -24,7 +24,7 @@ import psycopg2.extras
 
 from pvcapid.Daemon import config
 
-from daemon_lib.zkhandler import ZKConnection
+from daemon_lib.zkhandler import ZKHandler
 
 import daemon_lib.common as pvc_common
 import daemon_lib.ceph as pvc_ceph
@@ -103,8 +103,7 @@ def list_benchmarks(job=None):
         return {'message': 'No benchmark found.'}, 404
 
 
-@ZKConnection(config)
-def run_benchmark(self, zkhandler, pool):
+def run_benchmark(self, pool):
     # Runtime imports
     import time
     import json
@@ -123,6 +122,13 @@ def run_benchmark(self, zkhandler, pool):
         print('FATAL - failed to connect to Postgres')
         raise Exception
 
+    try:
+        zkhandler = ZKHandler(config)
+        zkhandler.connect()
+    except Exception:
+        print('FATAL - failed to connect to Zookeeper')
+        raise Exception
+
     print("Storing running status for job '{}' in database".format(cur_time))
     try:
         query = "INSERT INTO storage_benchmarks (job, result) VALUES (%s, %s);"
@@ -445,4 +451,7 @@ def run_benchmark(self, zkhandler, pool):
         raise BenchmarkError("Failed to store test results: {}".format(e), cur_time=cur_time, db_conn=db_conn, db_cur=db_cur, zkhandler=zkhandler)
 
     close_database(db_conn, db_cur)
+    zkhandler.disconnect()
+    del zkhandler
+
     return {'status': "Storage benchmark '{}' completed successfully.", 'current': 3, 'total': 3}