app.py

from pyabsa import available_checkpoints
from pyabsa import ATEPCCheckpointManager
import gradio as gr


def assign_sentiment_marker(sentiment_list, aspect_index):
    """
    This function returns a sentiment marker '+' for Positive, '-' for Negative, and '$' for any other sentiment.
    It maps the sentiment from the sentiment_list at the aspect_index to the respective marker.

    Parameters:
    sentiment_list (list): A list of sentiments.
    aspect_index (int): The index of the sentiment in sentiment_list to map to a marker.

    Returns:
    str: The sentiment marker.
    """

    # Define a dictionary to map sentiment labels to markers.
    sentiment_markers = {
        "Positive": "pos",
        "Negative": "neg"
    }

    # Fetch sentiment label from the sentiment_list using aspect_index.
    sentiment_label = sentiment_list[aspect_index]

    # Use get method on dictionary to fetch corresponding marker or default to '$' for unlisted sentiments.
    return sentiment_markers.get(sentiment_label, "neu")
    

def annotate_sentiment(tokens, aspect_positions, sentiment_list):
    """
    Function to post-process the output from the aspect extractor model.
    Annotates tokens based on sentiment, either positive (+) or negative (-).
    
    :param tokens: list of tokens to be processed
    :param aspect_positions: list of positions in tokens that refer to aspects
    :param sentiment_list: list of sentiments corresponding to each aspect
    :return: list of tuples where each tuple contains a token and its corresponding sentiment (if any)
    """
    annotated_tokens = []
    aspect_index = 0
    for i, token_group in enumerate(tokens):
        if aspect_index < len(aspect_positions) and i == aspect_positions[aspect_index]:
            for token in token_group:
                sentiment = assign_sentiment_marker(sentiment_list, aspect_index)
                annotated_tokens.append((token, sentiment))
            aspect_index += 1
        else:
            for token in token_group:
                annotated_tokens.append((token, None))

        # Add space between groups of tokens, if it's not the last group
        if i != len(tokens) - 1:
            annotated_tokens.append((' ', None))
    
    return annotated_tokens


def annotate_text_sentiment(text):
    """
    Interface function to extract aspects and their sentiments from the given text.
    Uses an aspect extractor model, then processes its output for sentiment annotation.
    
    :param text: string to be processed
    :return: list of tuples where each tuple contains a token from the text and its corresponding sentiment (if any)
    """
    aspect_extraction_result = aspect_extractor.extract_aspect(inference_source=[text], pred_sentiment=True)[0]
    tokens = aspect_extraction_result["tokens"]
    
    # If no aspects found, aspect_positions and sentiment_list are empty
    if len(aspect_extraction_result['position']) == 0:
        aspect_positions = []
        sentiment_list = []
    else:
        aspect_positions = [position[0]-1 for position in aspect_extraction_result['position']]
        sentiment_list = aspect_extraction_result["sentiment"]

    print(sentiment_list)
    annotated_tokens = annotate_sentiment(tokens, aspect_positions, sentiment_list)
    return annotated_tokens

# Initializing the aspect extractor model
checkpoint_map = available_checkpoints()
aspect_extractor = ATEPCCheckpointManager.get_aspect_extractor(checkpoint='english',
                                   auto_device=True  # False means load model on CPU
                                   )



demo1 = gr.Interface(
    annotate_text_sentiment,
    [
        gr.Textbox(
            label="Enter the text for aspect extraction and polarity detection",
            info="Example: The food was good, but the service was terrible.",
            lines=3,
        ),
    ],
    gr.HighlightedText(
        label="Aspect Detector based on DeBERTa",
        combine_adjacent=True,
        show_legend=True,
    ).style(color_map={"pos": "green", "neg": "red", "neu":"blue"}),
    theme=gr.themes.Base()
)


demo2 = gr.Interface(
    annotate_text_sentiment,
    [
        gr.Textbox(
            label="Enter the text for polarity detection",
            info="Example: The food was good, but the service was terrible.",
            lines=3,
        ),
    ],
    gr.HighlightedText(
        label="Aspect Detector based on Relational Graph Attention Networks, and BERT",
        combine_adjacent=True,
        show_legend=True,
    ).style(color_map={"pos": "green", "neg": "red", "neu":"blue"}),
    theme=gr.themes.Base()
)



demo = gr.TabbedInterface([demo1, demo2], ["Aspect Polarity Detection with Extraction", "Aspect Polarity Detection without Extraction"])

demo.launch()