app.py

import streamlit as st
import time
import pandas as pd
import io
from transformers import pipeline
from streamlit_extras.stylable_container import stylable_container
import plotly.express as px
import zipfile
import os
from comet_ml import Experiment # Comet ML is imported, but not used in the exact same way for caching

st.set_page_config(layout="wide", page_title="Named Entity Recognition App")

st.subheader("7-Persian Named Entity Recognition Web App", divider="red")
st.link_button("by nlpblogs", "https://nlpblogs.com", type="tertiary")

expander = st.expander("**Important notes on the 7-Persian Named Entity Recognition Web App**")
expander.write('''
        **Named Entities:** This 7-Persian Named Entity Recognition Web App predicts seven (7) labels (“person”, “location”, “money”, “organization”, “date”, “percent value”, “time”). Results are presented in an easy-to-read table, visualized in an interactive tree map, pie chart, and bar chart, and are available for download along with a Glossary of tags.    Please check and adjust the language settings in your computer, so the Persian characters are handled properly in your downloaded file.
        **How to Use:** Type or paste your text and press Ctrl + Enter. Then, click the 'Results' button to extract and tag entities in your text data.
        **Usage Limits:** Unlimited number of Result requests.
        
        **Customization:** To change the app's background color to white or black, click the three-dot menu on the right-hand side of your app, go to Settings and then Choose app theme, colors and fonts.
        **Technical issues:** If your connection times out, please refresh the page or reopen the app's URL.
        For any errors or inquiries, please contact us at [email protected]
    ''')

with st.sidebar:
    container = st.container(border=True)
    container.write("**Named Entity Recognition (NER)** is the task of extracting and tagging entities in text data. Entities can be persons, organizations, locations, countries, products, events etc.")
    st.subheader("Related NLP Web Apps", divider="red")
    st.link_button("14-Named Entity Recognition Web App", "https://nlpblogs.com/shop/named-entity-recognition-ner/14-named-entity-recognition-web-app/", type="primary")

COMET_API_KEY = os.environ.get("COMET_API_KEY")
COMET_WORKSPACE = os.environ.get("COMET_WORKSPACE")
COMET_PROJECT_NAME = os.environ.get("COMET_PROJECT_NAME")

if COMET_API_KEY and COMET_WORKSPACE and COMET_PROJECT_NAME:
    comet_initialized = True
else:
    comet_initialized = False
    st.warning("Comet ML not initialized. Check environment variables.")

# --- Caching the model with st.cache_resource ---
@st.cache_resource
def load_ner_model():
    
    return pipeline("token-classification", model="HooshvareLab/bert-fa-base-uncased-ner-peyma", aggregation_strategy="max")

# Load the model using the cached function
model = load_ner_model()
# --- End Caching ---

text = st.text_area("Type or paste your text below, and then press Ctrl + Enter", key='my_text_area')
st.write("**Input text**: ", text)

def clear_text():
    st.session_state['my_text_area'] = ""

st.button("Clear text", on_click=clear_text)
st.divider()

if st.button("Results"):
    if not text.strip(): # Add a check for empty input
        st.warning("Please enter some text to process.")
    else:
        with st.spinner("Wait for it...", show_time=True):
            # No need for time.sleep(5) here unless it's for artificial delay
            # The model is already loaded thanks to st.cache_resource
            text1 = model(text)

            df1 = pd.DataFrame(text1)
            pattern = r'[^\w\s]'
            df1['word'] = df1['word'].replace(pattern, '', regex=True)
            df2 = df1.replace('', 'Unknown')
            df = df2.dropna()

            # Initialize Comet ML experiment here, as it's per-run
            if comet_initialized:
                experiment = Experiment(
                    api_key=COMET_API_KEY,
                    workspace=COMET_WORKSPACE,
                    project_name=COMET_PROJECT_NAME,
                )
                experiment.log_parameter("input_text", text)
                experiment.log_table("predicted_entities", df)

            properties = {"border": "2px solid gray", "color": "blue", "font-size": "16px"}
            df_styled = df.style.set_properties(**properties)
            st.dataframe(df_styled)

            with st.expander("See Glossary of tags"):
                st.write('''
                '**word**': ['entity extracted from your text data']
                '**score**': ['accuracy score; how accurately a tag has been assigned to a given entity']
                '**entity_group**': ['label (tag) assigned to a given extracted entity']
                '**start**': ['index of the start of the corresponding entity']
                '**end**': ['index of the end of the corresponding entity']
                **What does B and I mean in front of each entity_group?**
                Supposing that there are two words (word A, word B).
                **B** indicates that word A is the beginning of an entity_group and **I** indicates that word B is inside that entity_group.
                For example, **Los** is the beginning of the entity_group **Location** and **Angeles** is inside the entity_group **Location**.
                Los (B-LOC) - Beginning of the entity_group **Location**
                Angeles (I-LOC) - Inside the entity_group **Location**
                ''')

            if df is not None and not df.empty: # Added check for empty DataFrame
                fig = px.treemap(df, path=[px.Constant("all"), 'word', 'entity_group'],
                                     values='score', color='entity_group')
                fig.update_layout(margin=dict(t=50, l=25, r=25, b=25))
                st.subheader("Tree map", divider="red")
                st.plotly_chart(fig)
                if comet_initialized:
                    experiment.log_figure(figure=fig, figure_name="entity_treemap")

            if df is not None and not df.empty: # Added check for empty DataFrame
                value_counts1 = df['entity_group'].value_counts()
                df1 = pd.DataFrame(value_counts1)
                final_df = df1.reset_index().rename(columns={"index": "entity_group"})
                col1, col2 = st.columns(2)
                with col1:
                    fig1 = px.pie(final_df, values='count', names='entity_group', hover_data=['count'], labels={'count': 'count'}, title='Percentage of predicted labels')
                    fig1.update_traces(textposition='inside', textinfo='percent+label')
                    st.subheader("Pie Chart", divider="red")
                    st.plotly_chart(fig1)
                    if comet_initialized:
                        experiment.log_figure(figure=fig1, figure_name="label_pie_chart")
                with col2:
                    fig2 = px.bar(final_df, x="count", y="entity_group", color="entity_group", text_auto=True, title='Occurrences of predicted labels')
                    st.subheader("Bar Chart", divider="red")
                    st.plotly_chart(fig2)
                    if comet_initialized:
                        experiment.log_figure(figure=fig2, figure_name="label_bar_chart")

            dfa = pd.DataFrame(
                data={
                    'word': ['entity extracted from your text data'], 'score': ['accuracy score; how accurately a tag has been assigned to a given entity'], 'entity_group': ['label (tag) assigned to a given extracted entity'],
                    'start': ['index of the start of the corresponding entity'],
                    'end': ['index of the end of the corresponding entity'],
                    })
            buf = io.BytesIO()
            with zipfile.ZipFile(buf, "w") as myzip:
                myzip.writestr("Summary of the results.csv", df.to_csv(index=False))
                myzip.writestr("Glossary of tags.csv", dfa.to_csv(index=False))

            with stylable_container(
                key="download_button",
                css_styles="""button { background-color: yellow; border: 1px solid black; padding: 5px; color: black; }""",
            ):
                st.download_button(
                    label="Download zip file",
                    data=buf.getvalue(),
                    file_name="zip file.zip",
                    mime="application/zip",
                )
                if comet_initialized:
                    experiment.log_asset(buf.getvalue(), file_name="downloadable_results.zip")

            st.divider()
            if comet_initialized:
                experiment.end()