Implement CoinGecko API Client with Cryptocurrency Data Retrieval

[HermanKoii]

Implement CoinGecko API Client with Cryptocurrency Data Retrieval

Description

Task

Create a coin gekko api

Acceptance Criteria

• API can fetch a list of cryptocurrencies
• API can retrieve details for a specific cryptocurrency
• API handles errors gracefully
• Implementation uses TypeScript
• Unit tests provide comprehensive coverage

Summary of Work

CoinGecko API Client Implementation

Overview

This pull request implements a robust CoinGecko API client that allows fetching cryptocurrency data with comprehensive error handling and type safety.

Key Features

• Fetch list of cryptocurrencies with customizable limit
• Retrieve detailed information for a specific cryptocurrency
• Full TypeScript type definitions
• Error handling for network and data retrieval issues

Implementation Details

1. CoinGekkoApi class with two primary methods:
   • getCoinList(limit?: number):
     • Retrieves top cryptocurrencies sorted by market cap
     • Default limit of 100 coins
     • Supports customizable limit
   • getCoinById(id: string):
     • Fetches detailed information for a specific cryptocurrency
     • Returns null for non-existent coins
     • Validates input coin ID

Technical Specifications

• Uses axios for HTTP requests
• TypeScript interface CoinData for type-safe data handling
• Default CoinGecko API base URL with configurable option
• Comprehensive error logging

Testing Approach

• Unit tests cover successful data retrieval
• Error scenarios tested, including:
  • Network failures
  • Non-existent coin lookups
  • Invalid input validation

Acceptance Criteria

✅ Fetch list of cryptocurrencies
✅ Retrieve individual cryptocurrency details
✅ Proper error handling
✅ TypeScript type definitions
✅ Comprehensive unit test coverage

Changes Made

• Created CoinGekkoApi class in src/index.ts
• Implemented getCoinList method to fetch cryptocurrency list
• Implemented getCoinById method to fetch specific cryptocurrency details
• Added TypeScript interface for CoinData
• Created comprehensive unit tests in src/index.spec.ts

Tests

• Verify getCoinList returns correct cryptocurrency data
• Verify getCoinList handles request limit correctly
• Verify getCoinById returns correct coin details
• Verify getCoinById returns null for non-existent coins
• Verify error handling for network failures

Signatures

Staking Key

0x1234567890123456789012345678901234567890: 0x1234567890123456789012345678901234567890

Public Key

0x1234567890123456789012345678901234567890: 0x1234567890123456789012345678901234567890