Digital transactions and real-time financial services are the norm these days. From online banking to stock trading platforms, modern finance would be unthinkable without the internet. Behind the scenes, a silent workhorse enables all our favourite services to work seamlessly, yet it is rarely discussed outside of technical circles. I'm talking about HTTP (Hypertext Transfer Protocol).

HTTP is the foundational protocol of the web. Originally designed to transfer hypertext documents (e.g., HTML pages), it has gradually evolved into a versatile protocol capable of handling a wide range of data types and applications. In the context of digital finance, HTTP plays a crucial role in enabling secure, efficient, and reliable communication between clients (like web browsers or mobile apps) and servers (like bank databases or trading platforms).

HTTP is well-suited for financial services mainly for its stateless nature, which allows each request to be independent of previous ones. As transactions in finance are discrete events, this simplifies the design of systems that need to handle a high volume of requests without maitaining complex session states. Additionally, HTTP's support for various methods (GET, POST, PUT, DELETE) allows for flexible interactions with financial data, such as retrieving account information, submitting transactions, or updating user profiles. This is particularly important in scenarios where platforms make use of open banking APIs to interact with third-party services.

Retrieving financial data over HTTP

One of the most common ways financial data is retrieved over HTTP is through RESTful APIs (Representational State Transfer). These APIs expose endpoints that clients can interact with using standard HTTP methods. For example, a stock trading platform might provide an endpoint like /api/stocks/{symbol} that allows users to retrieve real-time stock prices by sending a GET request:

// Example: Retrieving stock data via RESTful API
const getStockPrice = async (symbol) => {
  try {
    const response = await fetch(`https://api.example.com/stocks/${symbol}`, {
      method: 'GET',
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
      }
    });
    
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    
    const data = await response.json();
    return {
      symbol: data.symbol,
      price: data.currentPrice,
      change: data.priceChange,
      timestamp: data.lastUpdated
    };
  } catch (error) {
    console.error('Error fetching stock data:', error);
    throw error;
  }
};

// Usage
getStockPrice('AAPL').then(stock => {
  console.log(`${stock.symbol}: $${stock.price} (${stock.change}%)`);
});

Retrieving Bank Account Information over HTTP

Another common use case is retrieving bank account information using HTTP-based APIs. Many banks now offer APIs that allow third-party applications to access account details securely. Here's an example of how to retrieve bank account information:

// Example: Retrieving bank account information via RESTful API
const getBankAccountInfo = async (accountId) => {
  try {
    const response = await fetch(`https://api.yourbank.com/accounts/${accountId}`, {
      method: 'GET',
      headers: {
        'Authorization': 'Bearer YOUR_API_KEY',
        'Content-Type': 'application/json'
      }
    });
    
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    
    const data = await response.json();
    return {
      accountId: data.id,
      accountType: data.type,
      balance: data.balance,
      currency: data.currency,
      lastUpdated: data.lastUpdated
    };
  } catch (error) {
    console.error('Error fetching bank account information:', error);
    throw error;
  }
};

// Usage
getBankAccountInfo('123456789').then(account => {
  console.log(`Account ID: ${account.accountId}, Balance: ${account.balance} ${account.currency}`);
});

In both examples, the fetch function is used to send an HTTP GET request to the API endpoints. The response is parsed as JSON, and relevant information is extracted and returned.