Overview

You can interact directly with the smart contracts of the ooNodz app. On this page you will find all the information you need to access our services without going through our web interface.

Architecture

The implementation is built based on four Smart Contracts:

• AccessControl.sol: The purpose of this contract is to manage the various wallet roles used in the project's other contracts. It allows one or more admins to assign or revoke roles to other wallets. All Smart Contracts using this access role management model must inherit RoleBasedAccessControlled.

• NodeIdNFT.sol: This Smart Contract is an ERC721 "NFT" Contract representing the ownership of a NodeID. It uses 2 roles:

  • MINTER : wallets authorized to mint new tokens
  • BURNER : wallets authorized to burn existing tokens (the owner of a token is also authorized to burn his own token).

• Billing.sol: This Smart Contract handles the billing part: supported currencies, exchange rates to USD (for the moment only USD-stable ERC20 tokens are supported), VAT rates, pricing rates, deposit rate, authorized countries of residence. This Smart Contract defines a role: BILLING. Each wallet with the BILLING role can add/remove a currency in the list of supported currency, manage the list of VAT rate per country of residence, the list of authorized countries and pricing data.

• Subscription.sol: This is the main Smart Contract that receives subscriptions from customers. the overall subscription process is:

  • If customer is not yet registered, he must send a transaction to the register function with his country of residence.
  • Once customer is registered, he can send a transaction to the newSubscription function to create a new subscription.

  Before calling newSubscription, customer has to allow Subscription contract to transfer funds from his (ERC20) account, using the allowance function of ERC20. Funds received by the Subscription contract are immediately transfered to a destinationWallet configured on Subscription contract. Wallets with ADMIN role can change the destinationWallet.

Subscription Process

1. The user must be registered before starting the subscription process. He registers by calling the Register function from the Subscriptions Smart Contract.

2. The user must have a NodeID to validate. He can, through the NodeIdNFT Smart Contract:

   1. Import a NodeID : he proceeds to the deposit required to mint the blank NFT that will carry the NodeID ownership by calling the deposit function. Once the deposit is made, the user calls the mintBlank function to mint the blank NFT. The user then makes a POST call to the ooNodz API to upload the NodeID files into the ooNodz network. Once imported, the NodeID is automatically inserted into the minted NFT.
   2. Ask for a new NodeID : he proceeds to the deposit required to mint the NFT that will carry the NodeID ownership by calling the deposit function. Once the deposit is made, the user calls the mint function to mint the NFT.
   3. Use a NodeID already created or imported inside the ooNodz App that is not already used for an ongoing validation.

3. The user calls the ERC20 contract approve function corresponding to the currency chosen for payment of his subscription, specifying the amount he wishes to be debited by the ooNodz contract. This step is bypassed if he has previously approved an amount equal to or greater than the amount of the current subscription plus any other subscriptions previously made since this last approval.

4. The user calls the newSubscription function from the Subscriptions Smart Contract. Once validated, it triggers the launch of the node server. All the user has to do is allocate the AVAX staking required to start validation.

Roles

• ADMIN_ROLE : allowed to manage grant / revoke roles for other wallets. Allowed to change the destinationWallet of Subscription Smart Contract.
• MINTER_ROLE: allowed to mint new NodeIdNFT tokens.
• BURNER_ROLE: allowed to burn existing NodeIdNFT tokens.
• BILLING_ROLE: allowed to manage the list of supported currencies, VAT rates, authorized countries, pricing data.
• REFUNDER_ROLE: allowed to refund users for unused periods.

Implementation Details

• Project is using Hardhat for compiling, testing and deploying Smart Contracts.
• Solhint is the linter.
• The OpenZeppelin library is used to define standard Smart Contracts (ERC20, ERC721, AccessControl).
• All these Smart Contracts are Upgradeable using OpenZeppelin Upgradeable patterns & plugins
• hardhat-gas-reporter plugin is used to compute gas fees for all operations

Deployment Addresses

ooNodz Contracts

Contract	Avalanche Mainnet Address	Fuji Testnet Address
Subscriptions	0x59a90cD4fa3f6F9544fb26EEeE913a35d6E7772e	0x2743A3c6B1618AF4335559165c6D992d02cf2846
Billing	0xFF9a9cA3C1A49F74aB5D8233f11f7531f2Ef63c8	0xa05D8018B51A97b1b403A4630876317260e72B69
NodeIdNFT	0x7C98CBd78b2180659484B91b06728BF8ABfde3BB	0x85644e02E5eD82AA4ed37f231068Bc30E2C5C7a1
Subscriptions	0x8BD06F20766E48Da514370056aA72070aE57882b	0x89a89fE9B973E0474e983FD4baE5Ac09634fE598

Stable ERC20 Contracts

Contract	Avalanche Mainnet Address	Fuji Testnet Address
USDC (ERC20)	0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E	0x08123E97291e1562eD2fC12C1f3325c6c4783a77
USDT (ERC20)	0x9702230A8Ea53601f5cD2dc00fDBc13d4dF4A8c7	0x7B8FDF47e587BaF614213f31A56E17B5C984C119

GitLab

You can access our GitLab repository to read the ooNodz contracts.

Audit

The ooNodz smart contracts have been audited by Deepy.lu, an independant auditor based in Luxembourg.

You can access the full audit report here.

info

In the meantime, you can now access our application and subscribe to our services via our web interface.