from flask import Flask, render_template, jsonify from flask_socketio import SocketIO, emit from kafka import KafkaConsumer from kafka.errors import NoBrokersAvailable import json import threading import time from datetime import datetime from collections import defaultdict, deque import logging import os app = Flask(__name__) app.config['SECRET_KEY'] = 'sentiment-dashboard-secret' socketio = SocketIO(app, cors_allowed_origins="*") # In-memory storage for dashboard data sentiment_counts = {'positive': 0, 'negative': 0, 'neutral': 0} recent_tweets = deque(maxlen=50) # Keep last 50 tweets hourly_sentiment = defaultdict(lambda: {'positive': 0, 'negative': 0, 'neutral': 0}) logging.basicConfig(level=logging.INFO) logger = logging.getLogger(__name__) def create_kafka_consumer(max_retries=10, retry_delay=5): """Create Kafka consumer with retry logic""" for attempt in range(max_retries): try: consumer = KafkaConsumer( 'sentiment-results', bootstrap_servers=['kafka:9092'], value_deserializer=lambda m: json.loads(m.decode('utf-8')), consumer_timeout_ms=1000, auto_offset_reset='earliest', # Changed from 'latest' to 'earliest' enable_auto_commit=True, group_id='dashboard-group' # Added consumer group ) logger.info("Successfully connected to Kafka consumer!") return consumer except NoBrokersAvailable as e: logger.warning(f"Kafka not ready, attempt {attempt + 1}/{max_retries}. Retrying in {retry_delay}s...") time.sleep(retry_delay) except Exception as e: logger.error(f"Unexpected error connecting to Kafka: {e}") time.sleep(retry_delay) raise Exception(f"Could not connect to Kafka consumer after {max_retries} attempts") def kafka_consumer_thread(): """Background thread to consume processed tweets from Kafka""" try: # Wait for Kafka and Spark to be ready logger.info("Waiting for Kafka and Spark services to be ready...") time.sleep(10) # Reduced from 30 to 10 seconds consumer = create_kafka_consumer() logger.info("Connected to Kafka consumer for dashboard - waiting for processed tweets...") logger.info("Starting to poll for messages from sentiment-results topic...") message_count = 0 while True: try: # Poll for messages with timeout message_batch = consumer.poll(timeout_ms=1000) if message_batch: logger.info(f"Received batch with {len(message_batch)} topic partitions") for topic_partition, messages in message_batch.items(): logger.info(f"Processing {len(messages)} messages from {topic_partition}") for message in messages: try: tweet_data = message.value message_count += 1 logger.info(f"Message {message_count}: Received tweet data: {tweet_data}") # Update sentiment counts sentiment = tweet_data.get('sentiment', 'neutral') sentiment_counts[sentiment] += 1 # Add to recent tweets recent_tweets.append({ 'text': tweet_data.get('tweet_text', '')[:100] + '...' if len(tweet_data.get('tweet_text', '')) > 100 else tweet_data.get('tweet_text', ''), 'sentiment': sentiment, 'timestamp': datetime.now().strftime('%H:%M:%S'), 'author_id': tweet_data.get('author_id', 'Unknown') }) # Update hourly data hour = datetime.now().strftime('%H:00') hourly_sentiment[hour][sentiment] += 1 # Emit real-time update to connected clients socketio.emit('sentiment_update', { 'sentiment_counts': dict(sentiment_counts), 'recent_tweets': list(recent_tweets), 'hourly_data': dict(hourly_sentiment) }) logger.info(f"Processed tweet with sentiment: {sentiment} - Total counts: {dict(sentiment_counts)}") except Exception as e: logger.error(f"Error processing individual tweet data: {e}") else: # No messages received if message_count == 0: logger.info("No messages received yet, continuing to poll...") time.sleep(1) except Exception as e: logger.error(f"Error in polling loop: {e}") time.sleep(5) except Exception as e: logger.error(f"Error in Kafka consumer thread: {e}") @app.route('/') def dashboard(): """Main dashboard page""" return render_template('dashboard.html') @app.route('/api/data') def get_data(): """API endpoint to get current dashboard data""" data = { 'sentiment_counts': dict(sentiment_counts), 'recent_tweets': list(recent_tweets), 'hourly_data': dict(hourly_sentiment), 'total_tweets': sum(sentiment_counts.values()) } logger.info(f"API request - returning data: {data}") return jsonify(data) @socketio.on('connect') def handle_connect(): """Handle client connection""" logger.info("Client connected to dashboard") emit('sentiment_update', { 'sentiment_counts': dict(sentiment_counts), 'recent_tweets': list(recent_tweets), 'hourly_data': dict(hourly_sentiment) }) if __name__ == '__main__': # Start Kafka consumer in background thread consumer_thread = threading.Thread(target=kafka_consumer_thread, daemon=True) consumer_thread.start() logger.info("Starting sentiment dashboard on port 5000") logger.info("Dashboard will display data once Spark processes tweets from Kafka") # Fix for Werkzeug warning - use allow_unsafe_werkzeug for development socketio.run(app, host='0.0.0.0', port=5000, debug=False, allow_unsafe_werkzeug=True)