Esempio n. 1
0
    def __init__(self, intents=None, testing=False):
        self.td = TopicProcessor()
        self.cp = ConversationProcessor()
        self.convX, self.convy = self.cp.get_dataset()

        self.topX, self.topy = self.td.get_dataset()
        self.topy = np_utils.to_categorical(self.topy)
        self.top_classes = self.td.get_num_categories()
        self.top_sentence_length = self.td.get_sentence_length()
        self.graph = None
        self.seq2seqmodel = seq2seqmodel()
        if not testing:
            # Try to load an existing model from file
            try:
                clear_session()
                self.model, self.graph, self.sess = self._load_model()
            except (FileNotFoundError, OSError):
                # If the model doesn't exist, we'll have to build one
                model = self._build_model()
                self.model = self._train_model(model, self.convX, self.convy,
                                               self.topX, self.topy)
                self.model, self.graph, self.sess = self._load_model()
            # If the user hasn't supplied a location, use the default
            if not intents:
                intents = 'chatbot/corpus/output.json'

            with open(intents, 'r') as json_file:
                self.intents = json.load(json_file)
        else:
            # self._test_model(self.convX, self.convy, self.topX, self.topy)
            self._k_fold_test(self.convX, self.convy, self.topX, self.topy)
Esempio n. 2
0
class Conversation():
    """ 
    This model will learn from user input to bot output.
    Given the probability of the user's statement being of a certain
    type, the result will be a random item in the response list.
    """
    def __init__(self, intents=None, testing=False):
        self.td = TopicProcessor()
        self.cp = ConversationProcessor()
        self.convX, self.convy = self.cp.get_dataset()

        self.topX, self.topy = self.td.get_dataset()
        self.topy = np_utils.to_categorical(self.topy)
        self.top_classes = self.td.get_num_categories()
        self.top_sentence_length = self.td.get_sentence_length()
        self.graph = None
        self.seq2seqmodel = seq2seqmodel()
        if not testing:
            # Try to load an existing model from file
            try:
                clear_session()
                self.model, self.graph, self.sess = self._load_model()
            except (FileNotFoundError, OSError):
                # If the model doesn't exist, we'll have to build one
                model = self._build_model()
                self.model = self._train_model(model, self.convX, self.convy,
                                               self.topX, self.topy)
                self.model, self.graph, self.sess = self._load_model()
            # If the user hasn't supplied a location, use the default
            if not intents:
                intents = 'chatbot/corpus/output.json'

            with open(intents, 'r') as json_file:
                self.intents = json.load(json_file)
        else:
            # self._test_model(self.convX, self.convy, self.topX, self.topy)
            self._k_fold_test(self.convX, self.convy, self.topX, self.topy)

    def _load_model(self):
        """
        Load the model from the disk. This is the weights in an h5 file,
        and the structure in a JSON format.

        returns: keras model
        """
        directory = __file__.split('\\')
        directory = '/'.join(directory[:-1])
        #load_model = models.load_model(os.path.join(directory, 'model.h5'))
        with open(
                os.path.join(directory, 'trainedconversationalmodel-old.json'),
                'r') as open_file:
            load_model = open_file.read()
        load_model = model_from_json(load_model)
        load_model.load_weights(
            os.path.join(directory,
                         'trainedconversationalmodelweights-old.h5'))
        load_model._make_predict_function()
        self.graph = tf.get_default_graph()
        # self.graph.finalize()
        sess = K.get_session()
        print("Combined model was loaded from disk")
        return load_model, self.graph, sess

    def _save_model(self, model):
        """
        Save a trained model to the disk. The weights of the model is saved in
        a H5 file. The models structure is in a JSON file format.

        Args:
            model: The trained model you want to save to disk.
        """

        directory = __file__.split('\\')
        directory = '/'.join(directory[:-1])
        model.save(os.path.join(directory, 'model.h5'))
        json_model = model.to_json()
        with open(directory + '/trainedconversationalmodel.json',
                  'w') as open_file:
            open_file.write(json_model)
        model.save_weights(directory + '/trainedconversationalmodelweights.h5')

    def _build_model(self):
        """
        Build keras model and train it against the dataset.

        Args:
            X: input statements
            y: label of the input statement

        Returns:
            A trained keras model
        """
        conv_input = Input(shape=(self.cp.MAX_SEQUENCE_LENGTH, ),
                           name='conv_input')
        top_input = Input(shape=(self.top_sentence_length, ), name='top_input')
        inputs = concatenate([conv_input, top_input])
        embedding = Embedding(input_dim=1000, output_dim=40)(inputs)
        flatten = Flatten()(embedding)

        conv_layer_1 = Dense(units=600, activation='sigmoid')(flatten)
        conv_dropout_1 = Dropout(0.7)(conv_layer_1)
        conv_layer_2 = Dense(units=400, activation='sigmoid')(conv_dropout_1)
        conv_dropout_2 = Dropout(0.7)(conv_layer_2)
        conv_output = Dense(units=self.cp.n_classes,
                            activation='softmax',
                            name='conversation_output')(conv_dropout_2)

        topic_layer_1 = Dense(units=2000, activation='sigmoid',
                              init='normal')(flatten)
        topic_dropout_1 = Dropout(0.5)(topic_layer_1)
        topic_layer_2 = Dense(units=500, activation='sigmoid',
                              init='uniform')(topic_dropout_1)
        topic_dropout_2 = Dropout(0.5)(topic_layer_2)
        topic_output = Dense(units=self.top_classes,
                             activation='softmax',
                             name='topic_output')(topic_dropout_2)
        topic_optimizer = optimizers.RMSprop(lr=0.0001)

        model = Model(inputs=[conv_input, top_input],
                      outputs=[conv_output, topic_output])
        model.compile(optimizer=topic_optimizer,
                      loss='categorical_crossentropy',
                      metrics=['accuracy'])
        return model

    def _k_fold_test(self, statements, labels, sentences, topics):
        """
        Perform Kfold cross validation, this is a slightly different take on the _test_model function, as
        the X and Y datasets will be split into k partitions and then tests k times. This means that it will
        take considerably longer to get the final result, depending on the number of folds used.

        args:
            statements: the intent statements (X)
            labels: the intent classes (Y)
            sentences: the topic statements (X)
            topics: the topic classes (Y)
        """
        cv_scores_conv = []
        cv_scores_topic = []
        kfold = KFold(
            labels.shape[0], n_folds=10, shuffle=True, random_state=0
        )  # depreciated in sklearn, but works well with multi-label classification
        for train, test in kfold:
            model = self._build_model()
            model.fit([statements[train], sentences[train]],
                      [labels[train], topics[train]],
                      batch_size=742,
                      epochs=1300)
            score = model.evaluate([statements[test], sentences[test]],
                                   [labels[test], topics[test]])
            print(score[3] * 100, score[4] * 100)
            cv_scores_conv.append(score[3] * 100)
            cv_scores_topic.append(score[4] * 100)

        print("Intent Accuracy: %.2f%% (+/- %.2f%%)" %
              (np.mean(cv_scores_conv), np.std(cv_scores_conv)))
        print("Topic Accuracy: %.2f%% (+/- %.2f%%)" %
              (np.mean(cv_scores_topic), np.std(cv_scores_topic)))

    def _test_model(self, statements, labels, sentences, topics):
        """
        Perform a simple testing method by splitting the corpus into training and testing sets. This method
        will also output graphs for how the model performs during the training and testing methods. 

        I have disabled it it on MacOS as matplotlib doesn't work in virtualenvwrapper environments.

        args:
            statements: the intent statements (X)
            labels: the intent classes (Y)
            sentences: the topic statements (X)
            topics: the topic classes (Y)
        """
        X_conv_train, X_conv_test, y_conv_train, y_conv_test = train_test_split(
            statements, labels, test_size=0.5, random_state=0)
        X_topic_train, X_topic_test, y_topic_train, y_topic_test = train_test_split(
            sentences, topics, test_size=0.5, random_state=0)

        images_folder_loc = 'images/'
        model = self._build_model()
        training = model.fit([X_conv_train, X_topic_train],
                             [y_conv_train, y_topic_train],
                             validation_data=([X_conv_test, X_topic_test],
                                              [y_conv_test, y_topic_test]),
                             batch_size=X_conv_train.shape[0],
                             epochs=1500)
        print(training.history.keys())

        if platform != 'darwin':
            plt.plot(training.history['conversation_output_acc'], color='red')
            plt.plot(training.history['val_conversation_output_acc'],
                     color='green')
            plt.title('Conversation Accuracy')
            plt.xlabel('Epochs')
            plt.ylabel('Accuracy')
            plt.legend(['train', 'test'], loc='upper left')
            plt.savefig(str(images_folder_loc + 'conv_acc.png'))
            plt.clf()

            plt.plot(training.history['topic_output_acc'], color='red')
            plt.plot(training.history['val_topic_output_acc'], color='green')
            plt.title('Topic Accuracy')
            plt.xlabel('Epochs')
            plt.ylabel('Accuracy')
            plt.legend(['Training', 'Testing'], loc='upper left')
            plt.savefig(str(images_folder_loc + 'topic_acc.png'))
            plt.clf()

            plt.plot(training.history['conversation_output_loss'], color='red')
            plt.plot(training.history['val_conversation_output_loss'],
                     color='green')
            plt.title('Converation Loss')
            plt.xlabel('Epochs')
            plt.ylabel('Loss')
            plt.legend(['Training', 'Testing'], loc='upper left')
            plt.savefig(str(images_folder_loc + 'conv_loss.png'))
            plt.clf()

            plt.plot(training.history['topic_output_loss'], color='red')
            plt.plot(training.history['val_topic_output_loss'], color='green')
            plt.title('Topic Loss')
            plt.xlabel('Epochs')
            plt.ylabel('Loss')
            plt.legend(['Training', 'Testing'], loc='upper left')
            plt.savefig(str(images_folder_loc + 'topic_loss.png'))
            plt.clf()

        plot_model(model, to_file=str(images_folder_loc + 'model.png'))

        print(model.metrics_names)
        print(
            model.evaluate([X_conv_test, X_topic_test],
                           [y_conv_test, y_topic_test]))

    def _train_model(self, model, statements, labels, sentences, topics):
        """
        Train method for the pre-compiled model. Returns a trained model

        args:
            model: pre-compiled keras model to train
            statements: the intent statements (X)
            labels: the intent classes (Y)
            sentences: the topic statements (X)
            topics: the topic classes (Y)

        returns:
            model: the trained keras model
        """
        model.fit([statements, sentences], [labels, topics],
                  batch_size=statements.shape[0],
                  epochs=1)
        self._save_model(model)
        return model

    def encode(self, statement):
        """
        When the user inputs a statement into the chatbot. It will need to be converted
        to a sequence vector for the model to work with. This function is an abstraction of that
        process.

        Args:
            statement: statement that is to be converted to a vector.

        Returns:
            A sequence vector representing the user's input.
        """
        return self.cp.encode_statment(statement)

    def request(self, req, context=None, state=None):
        """
        This is the function that will be called by the chatbot, when the user inputs a statement.
        It will call the encode function of this class, use the model to predict the 
        probability that it is of all classes using a softmax function. The highest probability 
        is therefore deemed the correct one (with some error threshold checking).

        Args:
            req: statement that we need to predict the class for.

        Returns:
            (response, context_set). Response is the String that the chatbot should respond with.
            Context_set is the tag of the intent that the bot needs context for.
        """
        with self.sess.as_default():
            with self.graph.as_default():
                pred = self.model.predict(
                    [self.encode(req),
                     self.td.encode_statement(req)])
        statement_pred = pred[0]
        topic_pred = pred[1]
        topic_class = np.argmax(topic_pred)
        topic_confidence = topic_pred[0][topic_class]

        statement_class = np.argmax(statement_pred)
        statement_confidence = statement_pred[0][statement_class]

        pred_class = self.cp.get_class(statement_class)
        topic_pred_class = self.td.decode_topic(topic_class)
        context_set = None
        response = ''

        for intent in self.intents['intents']:
            if context:
                if intent['tag'] == state:
                    for index, value in enumerate(intent['context_filter']):
                        if value == context:
                            if 'context_set' in intent:
                                try:
                                    context_set = intent['context_set'][index]
                                except:
                                    context_set = None
                            response = intent['responses'][index]
                elif 'context_filter' in intent and intent['tag'] == pred_class:
                    for index, value in enumerate(intent['context_filter']):
                        if value == context:
                            if 'context_set' in intent:
                                try:
                                    context_set = intent['context_set'][index]
                                except:
                                    context_set = None
                            response = intent['responses'][index]
            elif intent['tag'] == pred_class and 'context_filter' not in intent:
                if 'context_set' in intent:
                    context_set = intent['context_set'][0]
                response = random.choice(intent['responses'])

        if not response:  # catch all
            #            response = 'I am not sure I understand, could you explain it to me further?'
            response = self.seq2seqmodel.decode_sequence(req)

        return response, context_set, pred_class, topic_pred_class, topic_confidence
Esempio n. 3
0
 def test_get_sentence_length(self):
     tp = TopicProcessor()
     test_length = 4
     tp.max_sentence_length = test_length
     max_sentence_length = tp.get_sentence_length()
     self.assertEqual(test_length, max_sentence_length)
Esempio n. 4
0
 def test__load_files(self):
     tp = TopicProcessor()
     statements, topics = tp._load_files()
     if not len(statements):
         self.fail()
Esempio n. 5
0
 def test_get_dataset(self):
     tp = TopicProcessor()
     X, y = tp.get_dataset()
     if not X[0].size > 1:
         self.fail()
Esempio n. 6
0
 def test_get_num_categories(self):
     tp = TopicProcessor()
     test_num = 4
     tp.num_topics = test_num
     num_topics = tp.get_num_categories()
     self.assertEqual(test_num, num_topics)
Esempio n. 7
0
 def test_init(self):
     tp = TopicProcessor()
Esempio n. 8
0
 def test_decode_topic(self):
     tp = TopicProcessor()
     original_topic = 15
     decoded_topic = tp.decode_topic(original_topic)
     self.assertNotEqual(original_topic, decoded_topic)
     self.assertEqual(decoded_topic, 'abuse')
Esempio n. 9
0
 def test__build_dictionary(self):
     tp = TopicProcessor()
     _, topics = tp._load_files()
     dictionary, reverse_dictionary, num_topics = tp._build_dictionarys(topics)
     if not len(dictionary) > 1:
         self.fail()
Esempio n. 10
0
 def test_encode_topic(self):
     tp = TopicProcessor()
     original_topic = 'abuse'
     encoded_topic = tp.encode_topic(original_topic)
     self.assertNotEqual(original_topic, encoded_topic)
     self.assertEqual(encoded_topic, 15)
Esempio n. 11
0
 def test_encode_statement(self):
     tp = TopicProcessor()
     original_statement = 'My parents hit me'
     new_statement = tp.encode_statement(original_statement)
     self.assertNotEqual(original_statement, new_statement)
Esempio n. 12
0
 def test__pad_lines(self):
     tp = TopicProcessor()
     padded_lines = tp._pad_lines([[40]])
     if not len(padded_lines[0]) > 39 or not 40 in padded_lines[0]:
         self.fail()
Esempio n. 13
0
 def test__vectorize_text(self):
     tp = TopicProcessor()
     statements, _ = tp._load_files()
     vectorized_text = tp._vectorize_text(statements)
     self.assertNotEqual(statements, vectorized_text)
Esempio n. 14
0
 def test__create_tokenizer(self):
     tp = TopicProcessor()
     statements, _ = tp._load_files()
     tokenizer = tp._create_tokenizer(statements)
     if not isinstance(tokenizer, keras.preprocessing.text.Tokenizer):
         self.fail()
Esempio n. 15
0
 def test__clean_text(self):
     tp = TopicProcessor()
     statements_1, topics_1 = tp._load_files()
     statements_2, topics_2 = tp._clean_text(statements_1, topics_1)
     self.assertNotEqual(statements_1, statements_2)