1 files changed, 104 insertions, 0 deletions
diff --git a/policyhandler/onap/health.py b/policyhandler/onap/health.py
new file mode 100644
index 0000000..eefa7d2
--- /dev/null
+++ b/policyhandler/onap/health.py
@@ -0,0 +1,104 @@
+"""generic class to keep track of app health"""
+
+# org.onap.dcae
+# ================================================================================
+# Copyright (c) 2017 AT&T Intellectual Property. All rights reserved.
+# ================================================================================
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============LICENSE_END=========================================================
+#
+# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+import uuid
+from threading import Lock
+from datetime import datetime
+
+class HealthStats(object):
+    """keep track of stats for calls"""
+    def __init__(self, name):
+        """keep track of stats for metrics calls"""
+        self._name = name or "stats_" + str(uuid.uuid4())
+        self._lock = Lock()
+        self._call_count = 0
+        self._error_count = 0
+        self._longest_timer = 0
+        self._total_timer = 0
+        self._last_success = None
+        self._last_error = None
+
+    def dump(self):
+        """returns dict of stats"""
+        dump = None
+        with self._lock:
+            dump = {
+                "call_count" : self._call_count,
+                "error_count" : self._error_count,
+                "last_success" : str(self._last_success),
+                "last_error" : str(self._last_error),
+                "longest_timer_millisecs" : self._longest_timer,
+                "ave_timer_millisecs" : (float(self._total_timer)/self._call_count \
+                                         if self._call_count else 0)
+            }
+        return dump
+
+    def success(self, timer):
+        """records the successful execution"""
+        with self._lock:
+            self._call_count += 1
+            self._last_success = datetime.now()
+            self._total_timer += timer
+            if not self._longest_timer or self._longest_timer < timer:
+                self._longest_timer = timer
+
+    def error(self, timer):
+        """records the errored execution"""
+        with self._lock:
+            self._call_count += 1
+            self._error_count += 1
+            self._last_error = datetime.now()
+            self._total_timer += timer
+            if not self._longest_timer or self._longest_timer < timer:
+                self._longest_timer = timer
+
+class Health(object):
+    """Health stats for multiple requests"""
+    def __init__(self):
+        """Health stats for application"""
+        self._all_stats = {}
+        self._lock = Lock()
+
+    def _add_or_get_stats(self, stats_name):
+        """add to or get from the ever growing dict of HealthStats"""
+        stats = None
+        with self._lock:
+            stats = self._all_stats.get(stats_name)
+            if not stats:
+                self._all_stats[stats_name] = stats = HealthStats(stats_name)
+        return stats
+
+    def success(self, stats_name, timer):
+        """records the successful execution on stats_name"""
+        stats = self._add_or_get_stats(stats_name)
+        stats.success(timer)
+
+    def error(self, stats_name, timer):
+        """records the error execution on stats_name"""
+        stats = self._add_or_get_stats(stats_name)
+        stats.error(timer)
+
+    def dump(self):
+        """returns dict of stats"""
+        with self._lock:
+            stats = dict((k, v.dump()) for (k, v) in self._all_stats.iteritems())
+
+        return stats