Unlocking the Potential of NFTs as Access Tokens

Traditional Subscription Model vs. In-App Crypto Subscription Model

In traditional subscription models, users register and complete transactions for a subscription plan, and their login credentials are stored in a database along with their subscription details. However, this approach has limitations. On the other hand, an in-app crypto subscription model uses NFTs as access tokens, providing a more secure and efficient way to manage subscriptions.

Benefits of Using NFTs as Access Tokens

Using NFTs as access tokens offers several benefits, including:

• Transferability: Users can easily transfer ownership of their subscription by trading the NFT.
• Security: NFTs provide a secure proof of ownership mechanism.
• Efficiency: NFTs eliminate the need for intermediaries, making the subscription process more efficient.

Setting Up an NFT Subscription Model

To set up an NFT subscription model, follow these steps:

1. Create an ERC-1155 Smart Contract: Use the OpenZeppelin library to create a smart contract that defines the NFT’s metadata and behavior.
2. Compile and Deploy the Contract: Compile the contract using Remix IDE and deploy it to the Ethereum network or any other EVM-based network such as Polygon.
3. Add the Subscription Model to the DApp: Use Web3.js to add the subscription model to the DApp’s frontend.
4. Interact with the Subscription Model: Use Web3.js to call functions inside the contract, such as adding a subscription plan, subscribing to a plan, checking if a user has an active subscription plan, and withdrawing revenue from the contract.

Example Code

Here’s an example of how to create an ERC-1155 smart contract using Solidity:

pragma solidity ^0.8.0;

import "https://github.com/OpenZeppelin/openzeppelin-solidity/contracts/token/ERC1155/SafeMath.sol";
import "undefinedgithub.com/OpenZeppelin/openzeppelin-solidity/contracts/token/ERC1155/Ownable.sol";

contract DFlix {
  // Mapping of plans to their metadata
  mapping(uint256 => Plan) public plans;

  // Mapping of subscribers to their plans
  mapping(address => Subscriber) public subscribers;

  // Event emitted when a new plan is added
  event NewPlan(uint256 planId, string name, uint256 price);

  // Event emitted when a user subscribes to a plan
  event Subscribed(address subscriber, uint256 planId);

  // Function to add a new plan
  function addPlan(uint256 planId, string memory name, uint256 price) public onlyOwner {
    plans[planId] = Plan(name, price);
    emit NewPlan(planId, name, price);
  }

  // Function to subscribe to a plan
  function subscribe(uint256 planId) public payable {
    // Check if the user has already subscribed to the plan
    require(subscribers[msg.sender].planId!= planId, "Already subscribed");

    // Check if the plan exists
    require(plans[planId].name!= "", "Plan does not exist");

    // Transfer the subscription fee to the contract owner
    payable(owner()).transfer(msg.value);

    // Update the subscriber's plan
    subscribers[msg.sender].planId = planId;
    subscribers[msg.sender].subscribedAt = block.timestamp;

    emit Subscribed(msg.sender, planId);
  }
}

This contract defines two mappings: plans and subscribers. The plans mapping stores the metadata of each plan, including its name and price. The subscribers mapping stores the subscription details of each user, including the plan they are subscribed to and the timestamp of their subscription.

The contract also defines two events: NewPlan and Subscribed. The NewPlan event is emitted when a new plan is added, and the Subscribed event is emitted when a user subscribes to a plan.

The contract has two functions: addPlan and subscribe. The addPlan function adds a new plan to the contract, and the subscribe function allows a user to subscribe to a plan.