X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2FNATUtil.py;h=36f9da3994441749e5ff515ff86766cfe8d55779;hb=de5e719fbd965e2f8e26b7f3a9cd597b572d7ab3;hp=aabcd36cdae92457bf2f5d52096c0b25a0dad426;hpb=2c0affb70d06918e6ba0c9409d4cb7afc39b603a;p=csit.git

diff --git a/resources/libraries/python/NATUtil.py b/resources/libraries/python/NATUtil.py
index aabcd36cda..36f9da3994 100644
--- a/resources/libraries/python/NATUtil.py
+++ b/resources/libraries/python/NATUtil.py
@@ -13,6 +13,7 @@
 
 """NAT utilities library."""
 
+from math import log2, modf
 from pprint import pformat
 from enum import IntEnum
 
@@ -95,6 +96,10 @@ class NATUtil:
             flag=u"NAT_IS_NONE"):
         """Set NAT44 address range.
 
+        The return value is a callable (zero argument Python function)
+        which can be used to reset NAT state, so repeated trial measurements
+        hit the same slow path.
+
         :param node: DUT node.
         :param start_ip: IP range start.
         :param end_ip: IP range end.
@@ -105,6 +110,8 @@ class NATUtil:
         :type end_ip: str
         :type vrf_id: int
         :type flag: str
+        :returns: Resetter of the NAT state.
+        :rtype: Callable[[], None]
         """
         cmd = u"nat44_add_del_address_range"
         err_msg = f"Failed to set NAT44 address range on host {node[u'host']}"
@@ -119,6 +126,18 @@ class NATUtil:
         with PapiSocketExecutor(node) as papi_exec:
             papi_exec.add(cmd, **args_in).get_reply(err_msg)
 
+        # A closure, accessing the variables above.
+        def resetter():
+            """Delete and re-add the NAT range setting."""
+            with PapiSocketExecutor(node) as papi_exec:
+                args_in[u"is_add"] = False
+                papi_exec.add(cmd, **args_in)
+                args_in[u"is_add"] = True
+                papi_exec.add(cmd, **args_in)
+                papi_exec.get_replies(err_msg)
+
+        return resetter
+
     @staticmethod
     def show_nat_config(node):
         """Show the NAT configuration.
@@ -140,8 +159,10 @@ class NATUtil:
 
         :param node: Topology node.
         :type node: dict
+        :returns: NAT44 summary data.
+        :rtype: str
         """
-        PapiSocketExecutor.run_cli_cmd(node, u"show nat44 summary")
+        return PapiSocketExecutor.run_cli_cmd(node, u"show nat44 summary")
 
     @staticmethod
     def show_nat_base_data(node):
@@ -197,10 +218,33 @@ class NATUtil:
         :returns: Value of max_translations_per_thread NAT44 parameter.
         :rtype: int
         """
-        from math import log2, modf
         rest, mult = modf(log2(sessions/(10*threads)))
         return 2 ** (int(mult) + (1 if rest else 0)) * 10
 
+    @staticmethod
+    def get_nat44_sessions_number(node, proto):
+        """Get number of established NAT44 sessions from actual NAT44 mapping
+        data.
+
+        :param node: DUT node.
+        :param proto: Required protocol - TCP/UDP/ICMP.
+        :type node: dict
+        :type proto: str
+        :returns: Number of established NAT44 sessions.
+        :rtype: int
+        :raises ValueError: If not supported protocol.
+        """
+        nat44_data = dict()
+        if proto in [u"UDP", u"TCP", u"ICMP"]:
+            for line in NATUtil.show_nat44_summary(node).splitlines():
+                sum_k, sum_v = line.split(u":") if u":" in line \
+                    else (line, None)
+                nat44_data[sum_k] = sum_v.strip() if isinstance(sum_v, str) \
+                    else sum_v
+        else:
+            raise ValueError(f"Unsupported protocol: {proto}!")
+        return nat44_data.get(f"total {proto.lower()} sessions", 0)
+
     # DET44 PAPI calls
     # DET44 means deterministic mode of NAT44
     @staticmethod
@@ -253,6 +297,10 @@ class NATUtil:
     def set_det44_mapping(node, ip_in, subnet_in, ip_out, subnet_out):
         """Set DET44 mapping.
 
+        The return value is a callable (zero argument Python function)
+        which can be used to reset NAT state, so repeated trial measurements
+        hit the same slow path.
+
         :param node: DUT node.
         :param ip_in: Inside IP.
         :param subnet_in: Inside IP subnet.
@@ -277,6 +325,18 @@ class NATUtil:
         with PapiSocketExecutor(node) as papi_exec:
             papi_exec.add(cmd, **args_in).get_reply(err_msg)
 
+        # A closure, accessing the variables above.
+        def resetter():
+            """Delete and re-add the deterministic NAT mapping."""
+            with PapiSocketExecutor(node) as papi_exec:
+                args_in[u"is_add"] = False
+                papi_exec.add(cmd, **args_in)
+                args_in[u"is_add"] = True
+                papi_exec.add(cmd, **args_in)
+                papi_exec.get_replies(err_msg)
+
+        return resetter
+
     @staticmethod
     def get_det44_mapping(node):
         """Get DET44 mapping data.
@@ -299,14 +359,12 @@ class NATUtil:
     def get_det44_sessions_number(node):
         """Get number of established DET44 sessions from actual DET44 mapping
         data.
-
         :param node: DUT node.
         :type node: dict
         :returns: Number of established DET44 sessions.
         :rtype: int
         """
         det44_data = NATUtil.get_det44_mapping(node)
-
         return det44_data.get(u"ses_num", 0)
 
     @staticmethod