Implements a GET request for the alerts API

src/service/clmcservice/__init__.py

@@ -76,6 +76,7 @@ def main(global_config, **settings):
 
     # add routes of the Alerts Configuration API
     config.add_route('alerts_configuration', '/alerts')
+    config.add_route('alerts_configuration_instance', '/alerts/{sfc_id}/{sfc_instance_id}')
 
-    config.scan()  # This method scans the packages and finds any views related to the routes added in the app configuration
+    config.scan()  # this method scans the packages and finds any views related to the routes added in the app configuration
     return config.make_wsgi_app()

src/service/clmcservice/alertsapi/views.py

@@ -88,6 +88,49 @@ class AlertsConfigurationAPI(object):
             "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/{0}/handlers".format(topic_id)
         }
 
+    @view_config(route_name='alerts_configuration_instance', request_method='GET')
+    def get_alerts(self):
+        """
+        The view for retrieving all alerts and Kapacitor resources registered for a specific service function chain instance.
+
+        :return: a list of objects, each object representing an alert and containing the policy ID, trigger ID, task ID, topic ID and kapacitor endpoints for these
+        """
+
+        kapacitor_host, kapacitor_port = self.request.registry.settings['kapacitor_host'], self.request.registry.settings['kapacitor_port']
+
+        # fetch the URL parameters
+        sfc_id, sfc_instance_id = self.request.matchdict["sfc_id"], self.request.matchdict["sfc_instance_id"]
+
+        # get all tasks from kapacitor
+        kapacitor_tasks_url = "http://{0}:{1}/kapacitor/v1/tasks".format(kapacitor_host, kapacitor_port)
+        all_tasks = get(kapacitor_tasks_url).json()["tasks"]
+
+        # fetch all alerts that are configured for this SFC instance
+        sfc_instance_tasks = []
+
+        # traverse every registered task and check if it is configured for this SFC instance
+        for task in all_tasks:
+
+            # get the configured variables of this alert
+            task_config = task["vars"]
+
+            # if configured for this SFC instance
+            if task_config["sfc"]["value"] == sfc_id and task_config["sfci"]["value"] == sfc_instance_id:
+
+                task_id = task["id"]
+                topic_id = task_id
+                policy_id = task_config["policy"]["value"]
+                trigger_id = task_config["eventID"]["value"]
+
+                # add it to the list of alerts for this SFC instance
+                sfc_instance_tasks.append({"policy": policy_id, "trigger": trigger_id,
+                                           "task_identifier": task_id, "topic_identifier": topic_id,
+                                           "task_api_endpoint": "/kapacitor/v1/tasks/{0}".format(task_id),
+                                           "topic_api_endpoint": "/kapacitor/v1/alerts/topics/{0}".format(topic_id),
+                                           "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/{0}/handlers".format(topic_id)})
+
+        return sfc_instance_tasks
+
     @view_config(route_name='alerts_configuration', request_method='DELETE')
     def delete_alerts_specification(self):
         """

src/test/clmctest/alerts/test_alerts.py

@@ -85,6 +85,7 @@ class TestAlerts(object):
         """
         Test is implemented using the following steps:
             * Send to clmc service a POST request with TOSCA alert spec. and resource spec. files
+            * Check that the registered alerts can be fetched with a GET request
             * Wait 10 seconds for Kapacitor to configure and start executing the defined tasks
             * Send some test requests to nginx to increase the load
             * Wait 15 seconds for alerts to be triggered
@@ -107,6 +108,7 @@ class TestAlerts(object):
             if clmc_service_host is not None and nginx_host is not None:
                 break
 
+        # create the alerts with a POST request
         print("Sending alerts specification to clmc service...")
         alerts_spec = join(dirname(__file__), "alerts_test_config.yaml")
         resources_spec = join(dirname(__file__), "resources_test_config.yaml")
@@ -121,8 +123,40 @@ class TestAlerts(object):
         assert "triggers_specification_errors" not in clmc_service_response, "Unexpected error was returned for triggers specification"
         assert "triggers_action_errors" not in clmc_service_response, "Unexpected error was returned for handlers specification"
 
+        sfc, sfc_instance = "MS_Template_1", "MS_Template_1_1"
+        assert (sfc, sfc_instance) == (clmc_service_response["service_function_chain_id"], clmc_service_response["service_function_chain_instance_id"])
         print("Alert spec sent successfully")
 
+        # check that the alerts can be fetched with a GET request
+        print("Validate that the alerts were registered and can be fetched with a GET request.")
+        response = get("http://{0}/clmc-service/alerts/{1}/{2}".format(clmc_service_host, sfc, sfc_instance))
+        assert response.status_code == 200
+        clmc_service_response = response.json()
+        clmc_service_response = sorted(clmc_service_response, key=lambda x: x["trigger"])  # sort by trigger so that the response can be compared to what's expected
+        assert clmc_service_response == [
+            {"policy": "scale_nginx_policy", "trigger": "high_requests", "task_identifier": "46fb8800c8a5eeeb04b090d838d475df574a2e6d854b5d678fc981c096eb6c1b",
+             "topic_identifier": "46fb8800c8a5eeeb04b090d838d475df574a2e6d854b5d678fc981c096eb6c1b",
+             "task_api_endpoint": "/kapacitor/v1/tasks/46fb8800c8a5eeeb04b090d838d475df574a2e6d854b5d678fc981c096eb6c1b",
+             "topic_api_endpoint": "/kapacitor/v1/alerts/topics/46fb8800c8a5eeeb04b090d838d475df574a2e6d854b5d678fc981c096eb6c1b",
+             "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/46fb8800c8a5eeeb04b090d838d475df574a2e6d854b5d678fc981c096eb6c1b/handlers"},
+            {"policy": "scale_nginx_policy", "trigger": "increase_in_active_requests", "task_identifier": "7a9867f9270dba6635ac3760a3b70bc929f5bd0f3bf582e45d27fbd437f528ca",
+             "topic_identifier": "7a9867f9270dba6635ac3760a3b70bc929f5bd0f3bf582e45d27fbd437f528ca",
+             "task_api_endpoint": "/kapacitor/v1/tasks/7a9867f9270dba6635ac3760a3b70bc929f5bd0f3bf582e45d27fbd437f528ca",
+             "topic_api_endpoint": "/kapacitor/v1/alerts/topics/7a9867f9270dba6635ac3760a3b70bc929f5bd0f3bf582e45d27fbd437f528ca",
+             "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/7a9867f9270dba6635ac3760a3b70bc929f5bd0f3bf582e45d27fbd437f528ca/handlers"},
+            {"policy": "scale_nginx_policy", "trigger": "increase_in_running_processes", "task_identifier": "f5edaeb27fb847116be749c3815d240cbf0d7ba79aee1959daf0b3445a70f2c8",
+             "topic_identifier": "f5edaeb27fb847116be749c3815d240cbf0d7ba79aee1959daf0b3445a70f2c8",
+             "task_api_endpoint": "/kapacitor/v1/tasks/f5edaeb27fb847116be749c3815d240cbf0d7ba79aee1959daf0b3445a70f2c8",
+             "topic_api_endpoint": "/kapacitor/v1/alerts/topics/f5edaeb27fb847116be749c3815d240cbf0d7ba79aee1959daf0b3445a70f2c8",
+             "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/f5edaeb27fb847116be749c3815d240cbf0d7ba79aee1959daf0b3445a70f2c8/handlers"},
+            {"policy": "deadman_policy", "trigger": "no_measurements", "task_identifier": "f7dab6fd53001c812d44533d3bbb6ef45f0d1d39b9441bc3c60402ebda85d320",
+             "topic_identifier": "f7dab6fd53001c812d44533d3bbb6ef45f0d1d39b9441bc3c60402ebda85d320",
+             "task_api_endpoint": "/kapacitor/v1/tasks/f7dab6fd53001c812d44533d3bbb6ef45f0d1d39b9441bc3c60402ebda85d320",
+             "topic_api_endpoint": "/kapacitor/v1/alerts/topics/f7dab6fd53001c812d44533d3bbb6ef45f0d1d39b9441bc3c60402ebda85d320",
+             "topic_handlers_api_endpoint": "/kapacitor/v1/alerts/topics/f7dab6fd53001c812d44533d3bbb6ef45f0d1d39b9441bc3c60402ebda85d320/handlers"}
+        ], "Incorrect response for GET alerts request"
+        print("Alert spec validated successfully")
+
         print("Wait 10 seconds for Kapacitor stream/batch tasks to start working...")
         sleep(10)
 
@@ -138,6 +172,7 @@ class TestAlerts(object):
         alert_logs = listdir(LOG_TEST_FOLDER_PATH)
         assert len(alert_logs) == 4, "4 log files must have been created - one for each alert defined in the specification."
 
+        # check the content of eac log file
         for alert_log in alert_logs:
             alert_log_path = join(LOG_TEST_FOLDER_PATH, alert_log)
 
@@ -152,6 +187,7 @@ class TestAlerts(object):
 
             assert valid, "Alert log content is invalid - {0}".format(alert_log_path)
 
+        # delete the alerts with a DELETE request
         with open(alerts_spec, 'rb') as alerts:
             files = {'alert-spec': alerts}
             response = delete("http://{0}/clmc-service/alerts".format(clmc_service_host), files=files)