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Function Signature 
public func evaluateTransaction(
    chainId: String,
    transaction: EvaluateTransactionParam,
    operationType: EvaluateTransactionOperationType? = nil
) async throws -> BlockaidValidateTrxRes
Parameters
  1. chainId: The chain identifier in CAIP-2 format (e.g., “eip155:1” for Ethereum mainnet)
  2. transaction: An EvaluateTransactionParam object containing:
    • to:* Destination address
    • value: (Optional) Transaction value in wei
    • data: (Optional) Transaction data for contract interactions
    • maxFeePerGas: (Optional) Maximum total fee per gas unit
    • maxPriorityFeePerGas: (Optional) Maximum priority fee per gas unit
    • gas: (Optional) Gas limit
    • gasPrice: (Optional) Gas price for legacy transactions
  3. operationType: Optional EvaluateTransactionOperationType with values:
    • .validation: Perform security validation only
    • .simulation: Perform transaction simulation only
    • .all: Perform both validation and simulation
Returns A BlockaidValidateTrxRes containing:
  • validation: Security validation results including:
    • classification: Type of potential security issue
    • description: Detailed description of the validation results
    • features: Array of detected security features, each containing:
      • type: Feature type
      • featureId: Unique identifier
      • description: Feature description
      • address: Related address if applicable
    • reason: Explanation of the validation result
    • resultType: Type of result
    • status: Validation status
  • simulation: Transaction simulation results including:
    • accountAddress: Address being analyzed
    • accountSummary: Summary of account state changes
    • addressDetails: Detailed information about involved addresses
    • assetsDiffs: Asset balance changes, containing:
      • asset: Asset information
      • in: Incoming transfers
      • out: Outgoing transfers
    • exposures: Risk exposure analysis
    • status: Simulation status
    • totalUsdDiff: Total USD value change
    • totalUsdExposure: Total USD value at risk
  • block: Block number used for evaluation
  • chain: Chain identifier
Example Usage 
// Basic transaction evaluation
do {
    let transaction = EvaluateTransactionParam(
        to: "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
        value: "1000000000000000000", // 1 ETH
        data: nil,
        maxFeePerGas: "30000000000",
        maxPriorityFeePerGas: "1500000000",
        gas: "21000",
        gasPrice: nil
    )

    let evaluation = try await portal.evaluateTransaction(
        chainId: "eip155:1",
        transaction: transaction,
        operationType: .all
    )

    // Check validation results
    if let validation = evaluation.validation {
        print("Security Status: \(validation.status)")

        if validation.status != "VALIDATED" {
            print("Warning: \(validation.description ?? "Unknown issue")")

            // Print detected security features
            validation.features.forEach { feature in
                print("Security Feature: \(feature.type)")
                print("Description: \(feature.description)")
            }
        }
    }

    // Check simulation results
    if let simulation = evaluation.simulation {
        print("Simulation Status: \(simulation.status)")

        // Print asset changes
        simulation.assetsDiffs.forEach { (token, diffs) in
            print("\nToken: \(token)")
            diffs.forEach { diff in
                print("Incoming transfers:")
                diff.in.forEach { transfer in
                    print(transfer)
                }
                print("Outgoing transfers:")
                diff.out.forEach { transfer in
                    print(transfer)
                }
            }
        }
    }
} catch {
    print("Evaluation failed: \(error)")
}

// Contract interaction evaluation
do {
    let transaction = EvaluateTransactionParam(
        to: "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
        value: "0",
        data: "0xa9059cbb000000000000000000000000742d35cc6634c0532925a3b844bc454e4438f44e0000000000000000000000000000000000000000000000000de0b6b3a7640000", // ERC20 transfer
        maxFeePerGas: nil,
        maxPriorityFeePerGas: nil,
        gas: "65000",
        gasPrice: "20000000000"
    )

    // Validate only
    let validation = try await portal.evaluateTransaction(
        chainId: "eip155:1",
        transaction: transaction,
        operationType: .validation
    )

    if let validationResult = validation.validation {
        // Handle potential security issues
        switch validationResult.status {
        case "VALIDATED":
            print("Transaction is safe")
        case "WARNING":
            print("Warning: \(validationResult.description ?? "Unknown warning")")
        case "BLOCKED":
            print("Blocked: \(validationResult.reason ?? "Unknown reason")")
        default:
            print("Unknown status: \(validationResult.status)")
        }
    }
} catch {
    print("Validation failed: \(error)")
}
Implementation Notes
  • Always evaluate transactions involving large amounts or contract interactions
  • Consider both validation and simulation results for comprehensive security
  • Handle different validation statuses appropriately in your UI
  • Gas parameters should be adjusted based on current network conditions
  • For contract interactions, carefully validate the data field