Implement Blockchain Controller to Expose API Endpoints

[Josue19-08]

📌 Issue: Implement Blockchain Controller to Expose API Endpoints

🔹 Description

Expose RESTful API endpoints for blockchain interactions, allowing external services to fetch NFT balances, metadata, and execute token transfers via the ERC-1155 contract on StarkNet Testnet.

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📂 Project Structure

• Controller: src/modules/blockchain/controllers/blockchain.controller.ts
• Service: src/modules/blockchain/services/starknet.service.ts
• DTOs: src/modules/blockchain/dtos/transfer.dto.ts

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🛠️ Tasks

• Create blockchain.controller.ts to handle HTTP requests.
• Implement the following API endpoints:
  • GET /blockchain/balance/:account/:tokenId → Returns the balance of a specific token for a given account.
  • GET /blockchain/token/:tokenId → Returns metadata for a specific token.
  • POST /blockchain/transfer → Transfers a token between two accounts.
• Ensure request validation using DTOs.
• Implement error handling for invalid requests.
• Integrate the controller with StarknetService.
• Write unit tests to validate:
  • Correct responses for balance and metadata retrieval.
  • Successful transfers via API.
  • Handling of invalid input parameters.
• Generate API documentation using Swagger/OpenAPI.

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✅ Acceptance Criteria

• The API should correctly expose blockchain-related functionalities.
• Swagger documentation must be available for all endpoints.
• API must handle errors gracefully and provide meaningful responses.
• Unit tests must pass before merging.