TradeStream

🔗Github Link

Technologies Used: Spring Boot, gRPC, H2 DB, JPA

Features

1. Real-Time Stock Trading: Enables users to buy and sell stocks seamlessly, with instant price retrieval and trade execution.
2. Live Price Updates: Provides continuous streaming of real-time stock price updates, allowing users to monitor market fluctuations instantly.
3. User-Centric Design: Supports a smooth user experience by handling all backend processes, including price fetching and balance updates, without requiring frontend input for pricing.
4. Scalable gRPC Architecture: Leverages gRPC for efficient, low-latency communication between microservices, ensuring quick and reliable data transmission.

Make Trade - Architecture

The stock trading service in “Trade Stream” enables users to buy and sell stocks through a streamlined gRPC-based communication system. The service is designed to interact with multiple microservices to ensure accurate price fetching, secure trading, and responsive feedback to the user.

Architecture Explanation:

1. User Request Initiation:

   • The process starts when a user sends a trade request to the aggregator-service via the /trade endpoint. The request contains crucial information such as the user_id, ticker, quantity, and the action (BUY or SELL).

2. Price Fetching:

   • Since the price is not directly passed from the frontend, the aggregator-service first interacts with the stock-service to fetch the current price of the stock. This is done through a synchronous gRPC call using the stockServiceBlockingStub.getStockPrice method, passing a StockPriceRequest that includes the stock’s ticker.

   • The stock-service processes the StockPriceRequest and returns the stock’s current price, which is then used by the aggregator-service to complete the trade.

3. Trade Execution:

   • With the fetched price, the aggregator-service constructs a StockTradeRequest and invokes the stockServiceStub.tradeStock method. This gRPC call triggers the actual trade process, which involves updating user data and the stock inventory in the user-service.

   • The user-service processes the trade by adjusting the user’s balance and stock holdings according to the action (BUY or SELL), and returns a StockTradeResponse to the aggregator-service. This response contains the updated details, including the total price of the trade and the user’s remaining balance.

4. Response to User:

   • Finally, the aggregator-service sends a StockTradeResponse back to the user, confirming the success of the transaction along with details such as the trade price, total cost, and updated balance.

Key Protobuf Definitions:

• StockTradeRequest: Contains fields like user_id, ticker, price, quantity, and TradeAction (either BUY or SELL).
• TradeAction: Enum defining the possible actions (BUY or SELL).
• StockTradeResponse: Returns the trade details, including total price and updated balance.

Price Update Streaming- Architecture

The stock trading service in “Trade Stream” enables users to buy and sell stocks through a streamlined gRPC-based communication system. The service is designed to interact with multiple microservices to ensure accurate price fetching, secure trading, and responsive feedback to the user.

Architecture Explanation:

1. User Request Initiation:

   • The process starts when a user sends a trade request to the aggregator-service via the /trade endpoint. The request contains crucial information such as the user_id, ticker, quantity, and the action (BUY or SELL).

2. Price Fetching:

   • Since the price is not directly passed from the frontend, the aggregator-service first interacts with the stock-service to fetch the current price of the stock. This is done through a synchronous gRPC call using the stockServiceBlockingStub.getStockPrice method, passing a StockPriceRequest that includes the stock’s ticker.

   • The stock-service processes the StockPriceRequest and returns the stock’s current price, which is then used by the aggregator-service to complete the trade.

3. Trade Execution:

   • With the fetched price, the aggregator-service constructs a StockTradeRequest and invokes the stockServiceStub.tradeStock method. This gRPC call triggers the actual trade process, which involves updating user data and the stock inventory in the user-service.

   • The user-service processes the trade by adjusting the user’s balance and stock holdings according to the action (BUY or SELL), and returns a StockTradeResponse to the aggregator-service. This response contains the updated details, including the total price of the trade and the user’s remaining balance.

4. Response to User:

   • Finally, the aggregator-service sends a StockTradeResponse back to the user, confirming the success of the transaction along with details such as the trade price, total cost, and updated balance.

Key Protobuf Definitions:

• StockTradeRequest: Contains fields like user_id, ticker, price, quantity, and TradeAction (either BUY or SELL).
• TradeAction: Enum defining the possible actions (BUY or SELL).
• StockTradeResponse: Returns the trade details, including total price and updated balance.

Motivation

The motivation behind the Trade Stream project was to empower individual investors by providing them with a real-time trading platform that combines ease of use with powerful functionality. Additionally, it served as a learning opportunity to explore and implement gRPC and microservices for efficient, scalable communication in financial applications.