aelf 백서 전문

Transfer the token from the sender to the contract State . TokenContract . TransferFrom . Send ( new TransferFromInput { From = Context . Sender , To = Context . Self , Symbol = TokenSymbol , Amount = playAmount } ) ; // Emit an event to notify listeners about the outcome Context . Fire ( new PlayOutcomeEvent { Amount = input . Value , Won = - playAmount } ) ; } return new Empty ( ) ; } // Withdraws a specified amount of tokens from the contract. // This method can only be called by the owner of the contract. // After the tokens are transferred, a WithdrawEvent is fired to notify any listeners about the withdrawal. public override Empty Withdraw ( Int64Value input ) { AssertIsOwner ( ) ; // Transfer the token from the contract to the sender State . TokenContract . Transfer . Send ( new TransferInput { To = Context . Sender , Symbol = TokenSymbol , Amount = input . Value } ) ; // Emit an event to notify listeners about the withdrawal Context . Fire ( new WithdrawEvent { Amount = input . Value , From = Context . Self , To = State . Owner . Value } ) ; return new Empty ( ) ; } // Deposits a specified amount of tokens into the contract. // This method can only be called by the owner of the contract. // After the tokens are transferred, a DepositEvent is fired to notify any listeners about the deposit. public override Empty Deposit ( Int64Value input ) { AssertIsOwner ( ) ; // Transfer the token from the sender to the contract State . TokenContract . TransferFrom . Send ( new TransferFromInput { From = Context . Sender , To = Context . Self , Symbol = TokenSymbol , Amount = input . Value } ) ; // Emit an event to notify listeners about the deposit Context . Fire ( new DepositEvent { Amount = input . Value , From = Context . Sender , To = Context . Self } ) ; return new Empty ( ) ; } // Transfers the ownership of the contract to a new owner. // This method can only be called by the current owner of the contract. public override Empty TransferOwnership ( Address input ) { AssertIsOwner ( ) ; // Set the new owner address State . Owner . Value = input ; return new Empty ( ) ; } // A method that read the contract's play amount limit public override PlayAmountLimitMessage GetPlayAmountLimit ( Empty input ) { // Wrap the value in the return type return new PlayAmountLimitMessage { MinimumAmount = MinimumPlayAmount , MaximumAmount = MaximumPlayAmount } ; } // A method that read the contract's current balance public override Int64Value GetContractBalance ( Empty input ) { // Get the balance of the contract var balance = State . TokenContract . GetBalance . Call ( new GetBalanceInput { Owner = Context . Self , Symbol = TokenSymbol } ) . Balance ; // Wrap the value in the return type return new Int64Value { Value = balance } ; } // A method that read the contract's owner public override StringValue GetOwner ( Empty input ) { return State . Owner . Value == null ? new StringValue ( ) : new StringValue { Value = State . Owner . Value . ToBase58 ( ) } ; } // Determines if the player is a winner. // This method generates a random number based on the current block height and checks if it's equal to 0. // If the random number is 0, the player is considered a winner. private bool IsWinner ( ) { var randomNumber = Context . CurrentHeight % 2 ; return randomNumber == 0 ; } // This method is used to ensure that only the owner of the contract can perform certain actions. // If the context sender is not the owner, an exception is thrown with the message "Unauthorized to perform the action." private void AssertIsOwner ( ) { Assert ( Context . Sender == State . Owner . Value , "Unauthorized to perform the action." ) ; } } } Building Smart Contract Build the new code with the following commands inside src folder: Terminal dotnet build You should see LotteryGame.dll.patched in the directory lottery_game/src/bin/Debug/net.6.0 Step 3 - Deploy Smart Contract Create A Wallet To send transactions on the aelf blockchain, you must have a wallet. Run this command to create aelf wallet. Terminal aelf-command create You will be prompted to save your account, please do save your account as shown below: Terminal ? Save account info into a file? ( Y/n ) Y Make sure to choose Y to save your account information. tip ℹ️ Note: If you do not save your account information (by selecting n or N), do not export the wallet password. Only proceed to the next step if you have saved your account information. Next, enter and confirm your password. Then export your wallet password as shown below: Linux and macOs Windows Terminal export WALLET_PASSWORD = "YOUR_WALLET_PASSWORD" Command Prompt $env :WALLET_PASSWORD = "YOUR_WALLET_PASSWORD" Acquire Testnet Tokens (Faucet) for Development To deploy smart contracts or execute on-chain transactions on aelf, you'll require testnet ELF tokens. Get ELF Tokens Go to https://faucet-ui.aelf.dev Enter your address and click Get Tokens . Deploy Smart Contract: The smart contract needs to be deployed on the chain before users can interact with it. Run the following command to deploy a contract. Remember to export the path of LotteryGame.dll.patched to CONTRACT_PATH. Linux and macOs Windows Terminal export CONTRACT_PATH = $( find ~+ . -path "*patched*" | head -n 1 ) Terminal aelf-deploy -a $WALLET_ADDRESS -p $WALLET_PASSWORD -c $CONTRACT_PATH -e https://tdvw-test-node.aelf.io/ Command Prompt $CONTRACT_PATH = Get-ChildItem -Recurse -Filter "*patched*" | Select-Object -First 1 -ExpandProperty FullName $env :CONTRACT_PATH = $CONTRACT_PATH Command Prompt aelf-deploy -a $env :WALLET_ADDRESS -p $env :WALLET_PASSWORD -c $env :CONTRACT_PATH -e https://tdvw-test-node.aelf.io/ Please wait for approximately 1 to 2 minutes. If the deployment is successful, it will provide you with the contract address. Copy the smart contract address from the address field Export your smart contract address: Linux and macOs Windows Terminal export CONTRACT_ADDRESS = "YOUR_SMART_CONTRACT_ADDRESS e.g. 2LUmicHyH4RXrMjG4beDwuDsiWJESyLkgkwPdGTR8kahRzq5XS" Command Prompt $env :CONTRACT_ADDRESS = "YOUR_SMART_CONTRACT_ADDRESS e.g. 2LUmicHyH4RXrMjG4beDwuDsiWJESyLkgkwPdGTR8kahRzq5XS" tip ℹ️ Note: You are to copy the smart contract address as we will be referencing it in the next steps! info 🎉 You have successfully deployed your dApp smart contract on the aelf testnet! In the next steps, we will be building the frontend components that allow us to interact with our deployed smart contract! Step 4 - Interact with Your Deployed Smart Contract Approving Smart Contract Spending Terminal aelf-command send ASh2Wt7nSEmYqnGxPPzp4pnVDU4uhj1XW9Se5VeZcX2UDdyjx -a $WALLET_ADDRESS -p $WALLET_PASSWORD -e https://tdvw-test-node.aelf.io Approve tip ℹ️ Note: ASh2Wt7nSEmYqnGxPPzp4pnVDU4uhj1XW9Se5VeZcX2UDdyjx is the contract address of Multitoken Contract on aelf Testnet dAppChain (tDVW). When prompted, enter the following parameters to approve the spending of 90 ELF tokens: Terminal Enter the params one by one, type `Enter` to skip optional param: ? Enter the required param <spender>: "INSERT_YOUR_CONTRACT_ADDRESS_HERE" ? Enter the required param <symbol>: ELF ? Enter the required param <amount>: 9000000000 Initializing Lottery Game Contract Terminal aelf-command send $CONTRACT_ADDRESS -a $WALLET_ADDRESS -p $WALLET_PASSWORD -e https://tdvw-test-node.aelf.io Initialize Output: Depositing funds into the Lottery Game Contract Terminal aelf-command send $CONTRACT_ADDRESS -a $WALLET_ADDRESS -p $WALLET_PASSWORD -e https://tdvw-test-node.aelf.io Deposit You will be prompted for the following: Terminal Enter the params one by one, type `Enter` to skip optional param: ? Enter the required param <value>: 20000 Output: Playing the Lottery Game Terminal aelf-command send $CONTRACT_ADDRESS -a $WALLET_ADDRESS -p $WALLET_PASSWORD -e https://tdvw-test-node.aelf.io Play Let's check the balance Terminal aelf-command call ASh2Wt7nSEmYqnGxPPzp4pnVDU4uhj1XW9Se5VeZcX2UDdyjx -a $WALLET_ADDRESS -p $WALLET_PASSWORD -e https://tdvw-test-node.aelf.io GetBalance You will be prompted for the following: Terminal Enter the required param <symbol>: ELF Enter the required param <owner>: $WALLET_ADDRESS Understanding Inter-Contract Calls in aelf In this section, we'll explore how inter-contract calls work in the aelf blockchain using the lottery game example from the tutorial. This will help you understand how different smart contracts can interact to perform complex operations. 1. Smart Contract Overview Lottery Contract : Manages the game, including buying tickets, drawing winners, and distributing prizes. Token Contract : Handles the token transactions needed for buying lottery tickets. 2. Ticket Purchase Process Initiating Purchase : When a user wants to buy a lottery ticket, they interact with the Lottery Contract. Token Transfer Requirement : The Lottery Contract must verify that the user has enough tokens and transfer those tokens to the lottery’s account to complete the purchase. 3. Initializing Contract Reference State Setting Contract Address : The Lottery Contract must first initialize its reference to the Token Contract by setting the correct contract address in its state. 4. Making an Inter-Contract Call Calling Token Contract : The Lottery Contract needs to interact with the Token Contract to transfer tokens. Method Invocation : It calls a method in the Token Contract, such as Transfer . Parameters : The call includes details like the sender’s address, the recipient’s address (the lottery account), and the amount of tokens. Encoding and Sending : The parameters are encoded into a transaction format and sent to the Token Contract. 5. Processing in the Token Contract Token Transfer : The Token Contract processes the transfer request by deducting tokens from the user’s account and adding them to the lottery account. Return Response : The Token Contract then returns a result indicating whether the transfer was successful or if it failed. 6. Handling the Response Lottery Contract’s Role : Once the Lottery Contract receives the response from the Token Contract, it checks if the transfer was successful. Next Steps : If successful, the Lottery Contract updates the user's lottery ticket entries and continues with the game logic. 7. Authorization and Security Permission Checks : Ensures that the Lottery Contract is authorized to invoke methods in the Token Contract. Secure Transactions : Ensures that token transfers are secure and correctly authorized. 8. Error Handling Failure Management : If the token transfer fails (e.g., due to insufficient funds), the Lottery Contract handles the error by potentially reverting the transaction or notifying the user. By following these steps, you can see how inter-contract calls in aelf allow different contracts to work together smoothly. This modular approach helps in building complex applications like a lottery game by ensuring secure and authorized interactions between contracts. 🎯 Conclusion 🎊 Congratulations! You've completed the Lottery Game Contract tutorial! Well done for mastering the steps and complexities involved. 🌟 📚 What You've Learned In this tutorial, you've explored: 🛠️ Setting up your development environment for aelf blockchain. 🎲 Developing a smart contract for a basic lottery game with state management and random number generation. 🚀 Deploying and interacting with your Lottery Game Contract on the aelf network. 🔍 Final Output By now, you should have: 📜 Successfully deployed your Lottery Game Contract on the aelf blockchain. 🎉 Deposited funds and played the lottery game using smart contract interactions. Ensure you've seen your ELF balance updated after playing the game to verify the contract's functionality. ➡️ What's Next? Now that you've tackled the Lottery Game Contract, consider exploring more advanced topics or other tutorials to expand your aelf blockchain development skills. 🚀 Keep innovating and building awesome decentralized applications! Happy coding! 😊 Step 1 - Setting up your development environment Step 2 - Develop Smart Contract Start Your Smart Contract Project Adding Your Smart Contract Code Building Smart Contract Step 3 - Deploy Smart Contract Step 4 - Interact with Your Deployed Smart Contract Approving Smart Contract Spending Initializing Lottery Game Contract Depositing funds into the Lottery Game Contract Playing the Lottery Game Understanding Inter-Contract Calls in aelf 1. Smart Contract Overview 2. Ticket Purchase Process 3. Initializing Contract Reference State 4. Making an Inter-Contract Call 5. Processing in the Token Contract 6. Handling the Response 7. Authorization and Security 8. Error Handling 🎯 Conclusion ## /quick-start/developers/dao-dapp On this page Description : This is the slightly more complex dApp in this guide. It covers mechanisms of a decentralized autonomous organization (DAO) dApp including creating a proposal, vote on a proposal, fetch all proposals, security considerations, and advanced data structures to ensure a fair and transparent DAO processes. Purpose : To teach you about complex logic implementation, security best practices, and efficient data management in smart contracts. Difficulty Level : Difficult Step 1 - Setting up your development environment Local Codespaces Basic knowledge of terminal commands IDE - Install VS Code Install Required Packages Install dotnet 6.0 SDK Install aelf contract templates Terminal dotnet new --install AElf.ContractTemplates AELF.ContractTemplates contains various predefined templates for the ease of developing smart contracts on the aelf blockchain. Install aelf deploy tool Terminal dotnet tool install --global aelf.deploy aelf.deploy is a utility tool for deploying smart contracts on the aelf blockchain. Please remember to export PATH after installing aelf.deploy. Install Node.js and Yarn Install Node.js Install Yarn Install aelf-command Linux and macOs Windows Terminal sudo npm i -g aelf-command Command Prompt npm i -g aelf-command aelf-command is a CLI tool for interacting with the aelf blockchain, enabling tasks like creating wallets and managing transactions. Provide required permissions while installing aelf-command globally. Install Git Install Git As we will be using a ready made project, we will require git to clone from the project. Visit aelf-devcontainer-template . Click the Use this template button. Choose Create a new repository . Enter a suitable repository name. Click Create repository . Within the GitHub interface of your new repository, click on Code . Select Codespaces . Click on the + sign to create a new Codespace. After some time, your workspace will load with the contents of the repository. You can now continue your development using GitHub Codespaces. Step 2 - Develop Smart Contract Project Setup Open your Terminal . Enter the following command to create a new project folder: Terminal mkdir capstone_aelf cd capstone_aelf Enter this command to create the capstone project. Terminal dotnet new aelf -n BuildersDAO Adding Your Smart Contract Code Open your project in your favorite IDE (like VSCode). Rename the src/Protobuf/contract/hello_world_contract.proto file to BuildersDAO.proto . After renaming the file, your working directory should look like this. That's it! Your project is now set up and ready to go 🚀 Defining Methods and Messages Let's add the RPC methods and message definitions to our Voting dApp. Open src/Protobuf/contract/BuildersDAO.proto Replace its contents with this code snippet. src/Protobuf/contract/BuildersDAO.proto syntax = "proto3" ; import "aelf/core.proto" ; import "aelf/options.proto" ; import "google/protobuf/empty.proto" ; import "Protobuf/reference/acs12.proto" ; // The namespace of this class option csharp_namespace = "AElf.Contracts.BuildersDAO" ; service BuildersDAO { // The name of the state class the smart contract is going to use to access // blockchain state option ( aelf . csharp_state ) = "AElf.Contracts.BuildersDAO.BuildersDAOState" ; option ( aelf . base ) = "Protobuf/reference/acs12.proto" ; // Actions -> Methods that change state of smart contract // This method sets up the initial state of our StackUpDAO smart contract rpc Initialize ( google . protobuf . Empty ) returns ( google . protobuf . Empty ) ; // This method allows a user to become a member of the DAO by taking in their // address as an input parameter rpc JoinDAO ( aelf . Address ) returns ( google . protobuf . Empty ) ; // This method allows a user to create a proposal for other users to vote on. // The method takes in a "CreateProposalInput" message which comprises of an // address, a title, description and a vote threshold (i.e how many votes // required for the proposal to pass) rpc CreateProposal ( CreateProposalInput ) returns ( Proposal ) ; // This method allows a user to vote on proposals towards a specific proposal. // This method takes in a "VoteInput" message which takes in the address of // the voter, specific proposal and a boolean which represents their vote rpc VoteOnProposal ( VoteInput ) returns ( Proposal ) ; // Views -> Methods that does not change state of smart contract // This method allows a user to fetch a list of proposals that had been // created by members of the DAO rpc GetAllProposals ( google . protobuf . Empty ) returns ( ProposalList ) { option ( aelf . is_view ) = true ; } // aelf requires explicit getter methods to access the state value, // so we provide these three getter methods for accessing the state // This method allows a user to fetch a proposal by proposalId rpc GetProposal ( google . protobuf . StringValue ) returns ( Proposal ) { option ( aelf . is_view ) = true ; } // This method allows a user to fetch the member count that joined DAO rpc GetMemberCount ( google . protobuf . Empty ) returns ( google . protobuf . Int32Value ) { option ( aelf . is_view ) = true ; } // This method allows a user to check whether this member is exist by address rpc GetMemberExist ( aelf . Address ) returns ( google . protobuf . BoolValue ) { option ( aelf . is_view ) = true ; } } // Message definitions message Member { aelf . Address address = 1 ; } message Proposal { string id = 1 ; string title = 2 ; string description = 3 ; repeated aelf . Address yesVotes = 4 ; repeated aelf . Address noVotes = 5 ; string status = 6 ; // e.g., "IN PROGRESS", "PASSED", "DENIED" int32 voteThreshold = 7 ; } message CreateProposalInput { aelf . Address creator = 1 ; string title = 2 ; string description = 3 ; int32 voteThreshold = 4 ; } message VoteInput { aelf . Address voter = 1 ; string proposalId = 2 ; bool vote = 3 ; // true for yes, false for no } message MemberList { repeated Member members = 1 ; } message ProposalList { repeated Proposal proposals = 1 ; } Understanding the Code 1. Define Syntax & Imports proto3 version. Import necessary Protobuf definitions and libraries. 2. RPC Methods Initialize : Set up initial state JoinDAO : User joins DAO. User's address is the function parameter. CreateProposal : User creates a proposal. User's address , title , description , vote threshold are the function parameter. VoteOnProposal : User votes on a proposal. User's address , proposal vote is the function parameter. GetAllProposals : Fetch list of proposals 3. Getter Metho