DevChain — Локальный Ethereum-нод для .NET разработки

--- name: devchain description: Help users run a local Ethereum dev chain, write integration tests, fork networks, debug transactions, or replace Hardhat/Anvil with Nethereum DevChain (.NET). Use this skill when the user mentions local Ethereum node, dev chain, test chain, Hardhat replacement, Anvil replacement, in-process blockchain, snapshot/revert, debug_traceTransaction, account impersonation, or anything involving a local EVM for development and testing with C# or .NET. user-invocable: true --- # Nethereum DevChain DevChain is a complete in-process Ethereum node for .NET. It runs the full EVM (up to Prague), mines blocks instantly, and needs no external dependencies — no Docker, no Geth, no Hardhat, no Anvil. ## When to Use This - Running a local Ethereum node for development or testing - Writing integration tests that need real EVM execution - Replacing Hardhat or Anvil with a .NET-native solution - Forking mainnet or L2s for local testing - Debugging transaction execution at the opcode level - Setting up Aspire-orchestrated dev environments ## Packages ```bash dotnet add package Nethereum.DevChain # Core in-process node dotnet add package Nethereum.DevChain.Server # HTTP JSON-RPC server ``` ## Quick Start — In-Process Node ```csharp using Nethereum.DevChain; using Nethereum.Web3; using Nethereum.Web3.Accounts; var account = new Account("0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"); var devChain = new DevChainNode(); await devChain.StartAsync(account); // Pre-funds with 10,000 ETH var web3 = devChain.CreateWeb3(account); // In-process, no HTTP // Standard Nethereum APIs work as-is var receipt = await web3.Eth.GetEtherTransferService() .TransferEtherAndWaitForReceiptAsync("0x70997970C51812dc3A010C7d01b50e0d17dc79C8", 1.0m); devChain.Dispose(); ``` ## Key Classes | Class | Package | Purpose | |-------|---------|---------| | `DevChainNode` | Nethereum.DevChain | Main in-process node | | `DevChainConfig` | Nethereum.DevChain | Chain configuration (ChainId, AutoMine, BlockGasLimit, etc.) | | `DevChainServerConfig` | Nethereum.DevChain.Server | HTTP server configuration | | `DevAccountManager` | Nethereum.DevChain.Server | HD wallet account management | | `DevChainHostedService` | Nethereum.DevChain.Server | ASP.NET Core hosted service | ## Configuration ```csharp var config = new DevChainConfig { ChainId = 1337, // Default: 1337 (Hardhat preset: 31337) BlockGasLimit = 30_000_000, AutoMine = true, // Mine instantly on each tx InitialBalance = BigInteger.Parse("10000000000000000000000") // 10,000 ETH }; var devChain = new DevChainNode(config); ``` Presets: `DevChainConfig.Default` (1337), `DevChainConfig.Hardhat` (31337), `DevChainConfig.Anvil` (31337). ## Factory Methods ```csharp // One-liner var devChain = await DevChainNode.CreateAndStartAsync(account); // In-memory (no SQLite) var devChain = DevChainNode.CreateInMemory(); // Multiple accounts var devChain = new DevChainNode(); await devChain.StartAsync(alice, bob); var accounts = await devChain.GenerateAndFundAccountsAsync(10); ``` ## Snapshot/Revert (Test Isolation) ```csharp var snapshot = await devChain.TakeSnapshotAsync(); // ... transactions ... await devChain.RevertToSnapshotAsync(snapshot); // Undo all changes ``` ## State Manipulation ```csharp await devChain.SetBalanceAsync(address, Web3.Convert.ToWei(1_000_000)); await devChain.SetNonceAsync(address, 100); await devChain.SetCodeAsync(address, bytecode); await devChain.SetStorageAtAsync(address, slot, value); ``` Via RPC: `hardhat_setBalance`, `hardhat_setCode`, `hardhat_setNonce`, `hardhat_setStorageAt` (also `anvil_*` aliases). ## Forking ```csharp var config = new DevChainConfig { ForkUrl = "https://eth.llamarpc.com", ForkBlockNumber = 19000000 }; var devChain = new DevChainNode(config); await devChain.StartAsync(account); ``` CLI: `nethereum-devchain -f https://eth.llamarpc.com --fork-block 19000000` ## Time Manipulation ```csharp devChain.DevConfig.AddTimeOffset(3600); // Advance 1 hour devChain.DevConfig.SetNextBlockTimestamp(1700000000); // Exact timestamp await devChain.MineBlockAsync(); ``` ## Debug Tracing ```csharp using Nethereum.CoreChain.Tracing; var traceConfig = new OpcodeTraceConfig { DisableMemory = true, DisableStack = false, DisableStorage = false }; var trace = await devChain.TraceTransactionAsync(txHash, traceConfig); ``` ## HTTP Server (CLI) ```bash nethereum-devchain # Defaults: port 8545, 10 accounts, auto-mine nethereum-devchain -p 8546 -a 20 # Custom port and accounts nethereum-devchain -f <url> # Fork mode nethereum-devchain --persist ./data # Persistent storage ``` ## Embedding HTTP Server in ASP.NET ```csharp using Nethereum.DevChain.Server.Configuration; using Nethereum.DevChain.Server.Hosting; using Nethereum.DevChain.Server.Server; var config = new DevChainServerConfig { ChainId = 31337, Storage = "memory" }; builder.Services.AddDevChainServer(config); builder.Services.AddHostedService<DevChainHostedService>(); ``` ## Integration Test Pattern ```csharp public class DevChainFixture : IAsyncLifetime { public DevChainNode Node { get; private set; } public Account Alice { get; private set; } public async Task InitializeAsync() { Alice = new Account("0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"); Node = new DevChainNode(new DevChainConfig { ChainId = 31337 }); await Node.StartAsync(Alice); } public Task DisposeAsync() { Node?.Dispose(); return Task.CompletedTask; } } // In test class: snapshot before each test, revert after public async Task InitializeAsync() => _snapshot = await _fixture.Node.TakeSnapshotAsync(); public async Task DisposeAsync() => await _fixture.Node.RevertToSnapshotAsync(_snapshot); ``` ## Supported RPC Methods Standard Ethereum (`eth_*`, `net_*`, `web3_*`), plus: - **Dev**: `evm_mine`, `evm_snapshot`, `evm_revert`, `evm_increaseTime`, `evm_setNextBlockTimestamp` - **Hardhat**: `hardhat_setBalance`, `hardhat_setCode`, `hardhat_setNonce`, `hardhat_setStorageAt`, `hardhat_impersonateAccount`, `hardhat_stopImpersonatingAccount` - **Anvil aliases**: `anvil_setBalance`, `anvil_setCode`, `anvil_setNonce`, `anvil_setStorageAt`, `anvil_mine`, `anvil_snapshot`, `anvil_revert` - **Debug**: `debug_traceTransaction`, `debug_traceCall` ## Hardhat/Anvil Migration Same default mnemonic (`test test test test test test test test test test test junk`), same derivation path (`m/44'/60'/0'/0/{index}`), same RPC methods, same chain ID (31337 with Hardhat/Anvil presets). Existing test scripts work without changes. For full documentation, see: https://docs.nethereum.com/docs/devchain/overview