From cf5360bd8be579d59fb284f97c920d6795b93bde Mon Sep 17 00:00:00 2001
From: Antonio Francisco <ajoaoff@gmail.com>
Date: Mon, 4 Oct 2021 18:30:55 -0300
Subject: [PATCH] Change how EVCs are loaded on startup

Instead of always trying to deploy EVCs on startup,
verify first if the old path is installed in the switches
and working. Fix #33.
---
 main.py                                   | 12 +++++++++---
 models.py                                 |  1 +
 requirements/run.in                       |  1 +
 settings.py                               |  3 +++
 tests/unit/models/test_link_protection.py |  1 +
 5 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/main.py b/main.py
index 1acb15eb..dd85d2fb 100644
--- a/main.py
+++ b/main.py
@@ -2,6 +2,7 @@
 
 NApp to provision circuits from user request.
 """
+import time
 from threading import Lock
 
 from flask import jsonify, request
@@ -54,14 +55,20 @@ def setup(self):
         self._lock = Lock()
 
         self.execute_as_loop(settings.DEPLOY_EVCS_INTERVAL)
+        self.load_time = time.time()
         self.load_all_evcs()
 
     def execute(self):
         """Execute once when the napp is running."""
         for circuit in tuple(self.circuits.values()):
             if circuit.is_enabled() and not circuit.is_active():
-                with circuit.lock:
-                    circuit.deploy()
+                if circuit.check_traces():
+                    circuit.activate()
+                    circuit.sync()
+                else:
+                    running_for = time.time() - self.load_time
+                    if running_for > settings.WAIT_FOR_OLD_PATH:
+                        circuit.deploy()
 
     def shutdown(self):
         """Execute when your napp is unloaded.
@@ -592,7 +599,6 @@ def _load_evc(self, circuit_dict):
         if evc.archived:
             return None
         evc.deactivate()
-        evc.current_path = Path([])
         evc.sync()
         self.circuits.setdefault(evc.id, evc)
         self.sched.add(evc)
diff --git a/models.py b/models.py
index d2295252..411d1e9f 100644
--- a/models.py
+++ b/models.py
@@ -12,6 +12,7 @@
 from kytos.core.helpers import get_time, now
 from kytos.core.interface import UNI
 from kytos.core.link import Link
+
 from napps.kytos.mef_eline import settings
 from napps.kytos.mef_eline.exceptions import FlowModException
 from napps.kytos.mef_eline.storehouse import StoreHouse
diff --git a/requirements/run.in b/requirements/run.in
index e173d70a..ccb9a293 100644
--- a/requirements/run.in
+++ b/requirements/run.in
@@ -1,2 +1,3 @@
 apscheduler
 requests
+glom
diff --git a/settings.py b/settings.py
index ca2d19ad..962766aa 100644
--- a/settings.py
+++ b/settings.py
@@ -15,5 +15,8 @@
 # EVC consistency interval
 DEPLOY_EVCS_INTERVAL = 60
 
+# Time to wait for old path to become available
+WAIT_FOR_OLD_PATH = 5 * DEPLOY_EVCS_INTERVAL
+
 # Prefix this NApp has when using cookies
 COOKIE_PREFIX = 0xaa
diff --git a/tests/unit/models/test_link_protection.py b/tests/unit/models/test_link_protection.py
index 078ce87c..c3120f8a 100644
--- a/tests/unit/models/test_link_protection.py
+++ b/tests/unit/models/test_link_protection.py
@@ -196,6 +196,7 @@ def test_handle_link_down_case_1(self, path_status_mocked,
         evc = EVC(**attributes)
 
         evc.current_path = evc.primary_path
+        evc.activate()
         current_handle_link_down = evc.handle_link_down()
         self.assertEqual(deploy_mocked.call_count, 0)
         deploy_to_mocked.assert_called_once()