Substrate 的 RPC 客户端之 Subxt 进阶篇​

    use sp_keyring::AccountKeyring;  
    use substrate_subxt::{  
        balances,  
        system::System,  
        DefaultNodeRuntime as Runtime,  
        ExtrinsicSuccess,  
    };  

    type AccountId = as System>::AccountId;  
    type Balance = as balances::Balances>::Balance;  

    fn main() {  
        let result: Result, Box<dyn std::error::Error + 'static>> =  
            async_std::task::block_on(async move {  
                env_logger::init();  

                let signer = AccountKeyring::Alice.pair();  

                let dest = AccountKeyring::Bob.to_account_id();  

                let cli = substrate_subxt::ClientBuilder::::new()  
                    .build()  
                    .await?;  
                let xt = cli.xt(signer, None).await?;  
                let xt_result = xt  
                    .watch()  
                    .submit(balances::transfer::(dest.clone().into(), 10_000))  
                    .await?;  
                Ok(xt_result)  
            });  
        match result {  
            Ok(extrinsic_success) => {  
                match extrinsic_success  
                    .find_event::<(AccountId, AccountId, Balance)>(  
                        "Balances", "Transfer",  
                    ) {  
                    Some(Ok((_from,_to, value))) => {  
                        println!("Balance transfer success: value: {:?}", value)  
                    }  
                    Some(Err(err)) => println!("Failed to decode code hash: {}", err),  
                    None => println!("Failed to find Balances::Transfer Event"),  
                }  
            }  
            Err(err) => println!("Error: {:?}", err),  
        }  
    }  

    Err(Rpc(Request(Error { code: MethodError(1002), message: "Verification Error: Execution(ApiError(\"Could not convert parameter `tx` between node and runtime: No such variant in enum MultiSignature\"))", data: Some(String("RuntimeApi(\"Execution(ApiError(\\\"Could not convert parameter `tx` between node and runtime: No such variant in enum MultiSignature\\\"))\")")) })))  

    use substrate_subxt::{  
        balances::{  
            AccountData,  
            Balances,  
        },  
        system::System,  
    };  

    use sp_runtime::{  
        generic::Header,  
        traits::{  
            BlakeTwo256,  
            IdentifyAccount,  
            Verify,  
        },  
        MultiSignature,  
        OpaqueExtrinsic,  
    };  

    #[derive(Debug, Clone, Eq, PartialEq)]  
    pub struct MyNodeRuntime;  

    impl System for MyNodeRuntime {  
        type Index = u32;  
        type BlockNumber = u32;  
        type Hash = sp_core::H256;  
        type Hashing = BlakeTwo256;  
        type AccountId = <as Verify>::Signer as IdentifyAccount>::AccountId;  
        type Address = Self::AccountId;  
        type Header = Header;  
        type Extrinsic = OpaqueExtrinsic;  
        type AccountData = AccountData<<Self as Balances>::Balance>;  
    }  

    impl Balances for MyNodeRuntime {  
        type Balance = u128;  
    }  

    use subxt::{  
        balances::Balances,  
        system::System,  
        ExtrinsicSuccess,  
    };  
    use node_template_runtime::Runtime;  
    use sp_runtime::OpaqueExtrinsic;  

    #[derive(Debug, Clone, Eq, PartialEq)]  
    pub struct MyNodeRuntime;  

    impl System for MyNodeRuntime {  
        type Index = as frame_system::Trait>::Index;  
        type BlockNumber = as frame_system::Trait>::BlockNumber;  
        type Hash = as frame_system::Trait>::Hash;  
        type Hashing = as frame_system::Trait>::Hashing;  
        type AccountId = as frame_system::Trait>::AccountId;  
        type Address = Self::AccountId;  
        type Header = as frame_system::Trait>::Header;  
        type Extrinsic = OpaqueExtrinsic;  
        type AccountData = as frame_system::Trait>::AccountData;  
    }  

    impl Balances for MyNodeRuntime {  
        type Balance = as pallet_balances::Trait>::Balance;  
    }