monasca-analytics/monasca_analytics/sml/decision_tree.py

102 lines
3.3 KiB
Python

#!/usr/bin/env python
# Copyright (c) 2016 FUJITSU LIMITED
#
# 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.
import logging
import numpy as np
from sklearn.metrics import classification_report
from sklearn import tree
import voluptuous
from monasca_analytics.sml.base import BaseSML
from monasca_analytics.util.validation_utils import NoSpaceCharacter
logger = logging.getLogger(__name__)
ANOMALY = 1
NON_ANOMALY = 0
N_SAMPLES = 1000
class DecisionTreeClassifier(BaseSML):
"""Anomaly detection based on the DecisionTreeClassifier algorithm"""
def __init__(self, _id, _config):
super(DecisionTreeClassifier, self).__init__(_id, _config)
self._nb_samples = int(_config['nb_samples'])
@staticmethod
def validate_config(_config):
decisiontree_schema = voluptuous.Schema({
'module': voluptuous.And(
basestring, NoSpaceCharacter()),
'nb_samples': voluptuous.Or(float, int)
}, required=True)
return decisiontree_schema(_config)
@staticmethod
def get_default_config():
return {
'module': DecisionTreeClassifier.__name__,
'nb_samples': N_SAMPLES
}
@staticmethod
def get_params():
return [
params.ParamDescriptor('nb_samples', type_util.Number(), N_SAMPLES)
]
def number_of_samples_required(self):
return self._nb_samples
def _generate_train_test_sets(self, samples, ratio_train):
num_samples_train = int(len(samples) * ratio_train)
data, labels = np.hsplit(samples, [-1])
X_train = np.array(data[:num_samples_train])
_labels = np.array(labels[:num_samples_train])
X_train_label = _labels.ravel()
X_test = np.array(data[num_samples_train:])
_labels = np.array(labels[num_samples_train:])
X_test_label = _labels.ravel()
return X_train, X_train_label, X_test, X_test_label
def _get_best_detector(self, train, label):
detector = tree.DecisionTreeClassifier()
detector.fit(train, label)
return detector
def learn_structure(self, samples):
X_train, X_train_label, X_test, X_test_label = \
self._generate_train_test_sets(samples, 0.75)
logger.info('Trainig with ' + str(len(X_train)) +
'samples; testing with ' + str(len(X_test)) + ' samples.')
dt_detector = self._get_best_detector(X_train, X_train_label)
Y_test = dt_detector.predict(X_test)
num_anomalies = Y_test[Y_test == ANOMALY].size
logger.info('Found ' + str(num_anomalies) +
' anomalies in testing set')
logger.info('Confusion Matrix: \n{}'.
format(classification_report(
X_test_label,
Y_test,
target_names=['no', 'yes'])))
return dt_detector