Decoding Cryptocurrency and Navigating the Developer's Realm
Tags: cpp, cryptoappdevelopmentwithcpp, cryptocurrency, apirequest
Published: 2024-01-24 12:17:06

In today's fast-paced financial landscape, the emergence of digital currency is beginning a new era, reshaping our understanding and utilization of money. Beyond the familiar names of Bitcoin and Ethereum, there are over 9,000 cryptocurrencies, each contributing to the evolving narrative of decentralized finance. But what sets digital currency apart, and why is it becoming a focal point of conversations?

## Cracking the Cryptocurrency Code: A User's Primer
Cryptocurrency, often dubbed the currency of the future, operates on blockchain technology. It's not just a digital version of traditional money; it represents a paradigm shift. Unlike conventional currencies controlled by central banks, cryptocurrency is decentralized and operates on a blockchain – a secure digital ledger.

Users can employ cryptocurrency for transactions, similar to regular money. However, it's more commonly viewed as an investment akin to stocks or precious metals. But, as with any investment, venturing into cryptocurrency requires diligent research to grasp its intricate workings.

Bitcoin, the inaugural cryptocurrency, was introduced by the mysterious Satoshi Nakamoto in a 2008 paper. Nakamoto aimed to create a system for electronic payments without the need for trust, giving birth to the groundbreaking concept of Bitcoin.

## Demystifying Blockchain: The User's Digital Checkbook
At the heart of cryptocurrency's magic lies blockchain – a colossal digital checkbook distributed across countless computers globally. Each transaction becomes a page, and these pages intertwine to form an unbroken chain.

Imagine a book where you write down everything you spend daily. Each page is similar to a block, whereas the entire book, a group of pages, is a blockchain. Every cryptocurrency user possesses a copy of this digital book. 

With each transaction, the records synchronize across all copies simultaneously, ensuring accuracy and uniformity. To thwart fraudulent activities, every transaction undergoes validation, employing techniques like proof of work or stake.

## Proof of Work & Proof of Stake: The Digital Power Play
Two popular mechanisms, proof of work and proof of stake, verify the legitimacy of transactions before incorporation into the blockchain. Participants in this validation process receive cryptocurrency rewards.

It's like a race where computers solve a puzzle to verify a group of transactions, and the winner gets a small amount of cryptocurrency.

 Bitcoin, for instance, awards approximately $200,000 worth of Bitcoin to the first computer validating a new block. Alternatively, some cryptocurrencies employ proof of stake, tying the verification capacity to the amount of cryptocurrency temporarily locked up by participants.

Proof of stake is more efficient than proof of work and facilitates faster transaction verification times. For instance, Bitcoin takes at least 10 minutes for a transaction, while Solana averages around 3,000 transactions per second using proof of stake – a notable speed increase.

## Consensus in the Crypto World: A Universal Agreement
Both proofs of stake and proof of work rely on consensus mechanisms to validate transactions. While individual users check transactions, most ledger holders must approve each verified transaction.

### Mining: Unearthing Digital Gold
Mining is creating new cryptocurrency units, typically as a reward for validating transactions. Once accessible to anyone, mining has become challenging, especially in proof-of-work systems like Bitcoin.
As the Bitcoin network grows, it gets more complicated and needs more power. 

The average person can't do it anymore because there are too many pros with better equipment.
Proof-of-work mining also consumes substantial electricity – Bitcoin alone surpasses Norway's annual electricity consumption. In contrast, proof-of-stake is less energy-intensive but requires participants to own cryptocurrency for involvement.

### Using Cryptocurrency: Beyond Digital Dollars
Cryptocurrencies like Bitcoin, Litecoin, or Ethereum offer more than a digital version of traditional money; they're perceived as investments akin to digital gold. Bitcoin, the most famous crypto, is like secure, decentralized gold.

Utilizing cryptocurrency for purchases often requires a crypto wallet, functioning as a digital purse interacting with the blockchain for sending and receiving crypto. However, it's crucial to note that crypto transactions aren't instantaneous; they require validation before completion. Thus, those diving into the cryptocurrency wave should brace for a dynamic ride.

## Empowering Developers through Digital Currency: A Symbiotic Relationship
Developers find themselves in a unique position, equipped in order to harness the potential and address the challenges presented by digital currencies:
**Blockchain Development:** Developers use blockchain to create decentralized applications (DApps) and smart contracts, reducing reliance on central authorities.
**Cryptocurrency Integration:** Seamlessly integrating cryptocurrencies into applications allows users to transact and invest within the ecosystem.
**Financial Innovation:** Digital currencies have become a testing ground for financial innovation, enabling developers to explore novel transaction methods and experiment with decentralized finance (DeFi) platforms.
**Enhanced Security:** Leveraging blockchain's cryptographic techniques, developers can fortify applications, ensuring robust security measures to protect user data and financial assets.
**Global Accessibility:** Digital currencies break geographical barriers and enable developers to create applications with global reach, offering financial services to unbanked populations.

## Crypto Data
The importance of [cryptocurrency data](https://tradermade.com/crypto) extends across various aspects of the financial, technological, and economic landscape. Here are key points highlighting the significance of cryptocurrency data:

### Market Analysis and Trading 
Cryptocurrency data provides [real-time information on crypto prices](https://tradermade.com/blog/how-to-get-live-crypto-prices), trading volumes, and market trends. Traders and investors use this data to make informed decisions, execute trades, and manage their portfolios.

### Investment Decisions
 Investors rely on cryptocurrency data to analyze historical performance, assess volatility, and identify potential investment opportunities. Access to accurate data is crucial for making strategic investment decisions.

### Risk Management 
Cryptocurrency data aids in risk assessment and management. Traders and investors use volatility metrics, historical price patterns, and other data points to gauge and mitigate risks associated with the crypto market.

### Blockchain Development 
Developers leverage blockchain-related data to understand network activities, validate transactions, and enhance the security of decentralized applications (DApps). Data from blockchain networks is fundamental for creating innovative and secure solutions.

### Market Research and Trends
Cryptocurrency data is essential for market research and trend analysis. Analysts and researchers use data to track user behavior, adoption rates, and emerging patterns, providing valuable insights into the evolving cryptocurrency landscape.

### Decentralized Finance (DeFi) 
In the context of DeFi, cryptocurrency data is crucial for assessing liquidity, interest rates, and other parameters. [DeFi platforms](https://tradermade.com/blog/defi-blockchain-applications-using-tradermade-data) rely on accurate and up-to-date data to operate decentralized lending, borrowing, and trading protocols seamlessly.

### Technology Innovation
Cryptocurrency data fuels technological innovation. Developers and entrepreneurs use data to create new blockchain-based applications and explore smart contract functionalities.
 

### Global Economic Impact 
Cryptocurrency data is increasingly recognized for impacting the global economy. Governments, financial institutions, and international organizations monitor and study crypto data to understand its influence on traditional financial systems and global economic dynamics.

### Educational Purposes 
Cryptocurrency data serves as a valuable educational resource. It helps individuals, institutions, and researchers understand the mechanics of blockchain technology, the economics of cryptocurrencies, and the implications for various industries.

## Fetching Live Cryptocurrency Market Data in C++.

The tutorial is designed to retrieve live cryptocurrency market data for BTC/USD. It utilizes the CURL library for making HTTP requests and the JSONCPP library for parsing JSON responses.

Also Read: Tutorial on [C++ WebSocket Client](https://tradermade.com/tutorials/how-to-build-your-first-cpp-websocket-client)

### Setting Up C++ Development Environment on Ubuntu
Install C++ Compiler:
Open a terminal and run the following command to install the GNU Compiler Collection (g++):

```
sudo apt-get update
sudo apt-get install g++
```

Install CURL Library:
Install the CURL library for making HTTP requests:

```
sudo apt-get install libcurl4-openssl-dev
```
Install JSONCPP Library:
Install the JSONCPP library for parsing JSON:

```
sudo apt-get install libjsoncpp-dev
```

## Getting API Key from TraderMade

**Sign Up on TraderMade:** Visit the [TraderMade website](https://tradermade.com/) and [sign up](https://tradermade.com/signup) for an account.
**Obtain API Key:** After signing in, navigate to the API section or contact TraderMade support to obtain your API key.
**Documentation:** Please visit the [documentation](https://tradermade.com/docs/restful-api) page for more details.

## Writing the C++ Program

### Include Necessary Libraries
The code begins by including essential libraries:

```
#include <iostream>
#include <string>
#include <curl/curl.h>
#include <json/json.h>
```

**Namespace Declaration:**
The program uses the std namespace for standard C++ functionality:

```
using namespace std;
```
**Callback Function for CURL:**
Defines a callback function (WriteCallback) to handle CURL's response:

```
size_t WriteCallback(void *contents, size_t size, size_t nmemb, void *userp) {
    ((string*)userp)->append((char*)contents, size * nmemb);
    return size * nmemb;
}
```
**Functions for CURL Request and JSON Parsing:**
performCurlRequest: Initiates a CURL request and retrieves the response.

```
bool performCurlRequest(const string& url, string& response) {
    // (CURL setup and execution)
}
parseJsonResponse: Parses the JSON response using the JSONCPP library.
bool parseJsonResponse(const string& jsonResponse, Json::Value& parsedRoot) {
    // (JSON parsing setup)
}
```
**Main Function:**
The main function initiates the program:

```
int main() {
    // (API URL and response string initialization)
}
```
**API URL and CURL Initialization:**
Sets up the API URL for fetching cryptocurrency data and initializes CURL:

```
string api_url = "https://marketdata.tradermade.com/api/v1/live?currency=BTCUSD&api_key=API_KEY";
string response;
curl_global_init(CURL_GLOBAL_DEFAULT);
```
**Performing CURL Request:**
Calls performCurlRequest to execute the CURL request:

```
if (performCurlRequest(api_url, response)) {
    // (JSON parsing and data extraction)
}
```
**JSON Parsing and Data Extraction:**
Utilizes parseJsonResponse to parse the JSON response and extract bid and ask prices:

```
Json::Value root;
if (parseJsonResponse(response, root)) {
    // (Extracting bid and ask prices from JSON)
}
```
**Displaying Results:**
Displays bid and ask prices to the console:

```
const Json::Value quotes = root["quotes"];
for (const Json::Value &quote : quotes) {
    if (quote.isMember("bid") && quote.isMember("ask")) {
        double bid = quote["bid"].asDouble();
        double ask = quote["ask"].asDouble();
        cout << "Bid: " << bid << ", Ask: " << ask << endl;
    }
}
```
**CURL Cleanup:**
Cleans up CURL resources before program exit:

```
curl_global_cleanup();
return 0;
```
The program fetches live cryptocurrency market data, demonstrating the use of CURL for HTTP requests and JSONCPP for parsing JSON responses.

Hurray! Our output is ready

```
{
  "endpoint": "live",
  "quotes": [
    {
      "ask": 39943.14,
      "base_currency": "BTC",
      "bid": 39888.32,
      "mid": 39915.73,
      "quote_currency": "USD"
    }
  ],
  "requested_time": "Wed, 24 Jan 2024 07:14:42 GMT",
  "timestamp": 1706080483
}
```
**We have a full program here:**

```
#include <iostream>
#include <string>
#include <curl/curl.h>
#include <json/json.h>

using namespace std;

// Callback function to handle curl's response
size_t WriteCallback(void *contents, size_t size, size_t nmemb, void *userp) {
    ((string*)userp)->append((char*)contents, size * nmemb);
    return size * nmemb;
}

// Function to perform CURL request
bool performCurlRequest(const string& url, string& response) {
    CURL *curl = curl_easy_init();
    if (!curl) {
        cerr << "Failed to initialize CURL" << endl;
        return false;
    }

    curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response);

    CURLcode res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);

    if (res != CURLE_OK) {
        cerr << "curl_easy_perform() failed: " << curl_easy_strerror(res) << endl;
        return false;
    }

    return true;
}

// Function to parse JSON response
bool parseJsonResponse(const string& jsonResponse, Json::Value& parsedRoot) {
    Json::CharReaderBuilder builder;
    Json::CharReader *reader = builder.newCharReader();
    string errs;

    bool parsingSuccessful = reader->parse(jsonResponse.c_str(), jsonResponse.c_str() + jsonResponse.size(), &parsedRoot, &errs);
    delete reader;

    if (!parsingSuccessful) {
        cerr << "Failed to parse JSON: " << errs << endl;
        return false;
    }

    return true;
}

int main() {
    string api_url = "https://marketdata.tradermade.com/api/v1/live?currency=BTCUSD&api_key=API_KEY";
    string response;

    curl_global_init(CURL_GLOBAL_DEFAULT);

    if (performCurlRequest(api_url, response)) {
        Json::Value root;
        if (parseJsonResponse(response, root)) {
            const Json::Value quotes = root["quotes"];
            for (const Json::Value &quote : quotes) {
                if (quote.isMember("bid") && quote.isMember("ask")) {
                    double bid = quote["bid"].asDouble();
                    double ask = quote["ask"].asDouble();
                    cout << "Bid: " << bid << ", Ask: " << ask << endl;
                }
            }
        }
    }

    curl_global_cleanup();
    return 0;
}
```

### Final Remarks
This tutorial is a foundation for building more complex cryptocurrency-related applications using C++.

Feel free to run this code in your development environment, and don't forget to replace "API_KEY" with a valid API key for the specified URL. This tutorial provides a practical example of making API requests, handling responses, and parsing JSON data in a C++ program.