新一代公链代表Solana（9） --- 如何用VS Code开发Solana智能合约

Solana智能合约可以使用Rust编写，所以要学习使用VS Code开发Solana智能合约，首先你得掌握如何在VS Code上面编写Rust程序。这里同学们可以参考之前的文章：

Rust开发环境搭建Visual Studio Code

Rust从入门到暴走系列

1.创建工程

在自己的workspace下，用cargo创建一个项目, 进入项目目录，添加Solana SDK依赖

luca@LucadeMacBook-Air rust-workspace % cargo new  --lib helloworld                      
     Created library `helloworld` package
luca@LucadeMacBook-Air rust-workspace % 
luca@LucadeMacBook-Air rust-workspace % cd helloworld 
luca@LucadeMacBook-Air helloworld % 
luca@LucadeMacBook-Air helloworld % cargo add solana-program
    Updating crates.io index
      Adding solana-program v1.18.9 to dependencies.
    Updating crates.io index

用VS Code打开项目

2.编写合约代码

在 src/lib.rs文件中，填入如下合约代码：

use solana_program::{
    account_info::{AccountInfo, next_account_info},
    entrypoint,
    entrypoint::ProgramResult,
    pubkey::Pubkey,
    msg,
};


// Declare and export the program's entrypoint
entrypoint!(process_instruction);

// Program entrypoint's implementation
pub fn process_instruction(
    _program_id: &Pubkey, // Public key of the account the hello world program was loaded into
    accounts: &[AccountInfo], // The account to say hello to
    _instruction_data: &[u8], // Ignored, all helloworld instructions are hellos
) -> ProgramResult {

    // Iterating accounts is safer than indexing
    let accounts_iter = &mut accounts.iter();

    // Get the account to say hello to
    let account = next_account_info(accounts_iter)?;
            
    msg!("Hello World Rust program entrypoint from {}", account.key);

    Ok(())
}

3.构建项目

在Cargo.toml中添加：

[features]
no-entrypoint = []

[lib]
crate-type = ["cdylib", "lib"]

修改后的Cargo.toml完整配置为

[package]
name = "helloworld"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
solana-program = "1.18.9"

[features]
no-entrypoint = []

[lib]
crate-type = ["cdylib", "lib"]

构建：

luca@LucadeMacBook-Air helloworld % cargo build-sbf
   Compiling proc-macro2 v1.0.79
   Compiling unicode-ident v1.0.12
   Compiling version_check v0.9.4
   .........................
   Compiling bincode v1.3.3
   Compiling helloworld v0.1.0 (/Users/luca/dev/rust-workspace/helloworld)
    Finished release [optimized] target(s) in 34.78s

生成deploy文件

但是同学们可能会遇到这个报错：

luca@LucadeMacBook-Air helloworld % cargo-build-sbf
error: package `solana-program v1.18.9` cannot be built because it requires rustc 1.75.0 or newer, while the currently active rustc version is 1.68.0-dev
Either upgrade to rustc 1.75.0 or newer, or use
cargo update -p [email protected] --precise ver
where `ver` is the latest version of `solana-program` supporting rustc 1.68.0-dev

然后你会检查自己的Rust版本,是1.77.1，高于1.75.0。

luca@LucadeMacBook-Air helloworld % rustc -V
rustc 1.77.1 (7cf61ebde 2024-03-27)

这个时候你可能会陷入疑惑。但其实cargo-build-sbf使用的是自带的rustc版本1.68.0，不会使用默认的rust版本

luca@LucadeMacBook-Air helloworld % cargo-build-sbf --version
solana-cargo-build-sbf 1.17.25
platform-tools v1.37
rustc 1.68.0

我们可以考虑升级一下，然后就可以正常构建了

solana-install init 1.18.9

4.发布智能合约

设置testnet

luca@LucadeMacBook-Air helloworld % solana config set --url https://api.testnet.solana.com  
Config File: /Users/luca/.config/solana/cli/config.yml
RPC URL: https://api.testnet.solana.com 
WebSocket URL: wss://api.testnet.solana.com/ (computed)
Keypair Path: /Users/luca/.config/solana/id.json 
Commitment: confirmed

发布合约

solana program deploy /Users/luca/dev/rust-workspace/helloworld/target/deploy/helloworld.so

Program Id: BiEjWMFBfRCup21wQMcC7TxioLQZcnFxBXWKSxZoGV1Q

查看浏览器记录：
https://solscan.io/account/BiEjWMFBfRCup21wQMcC7TxioLQZcnFxBXWKSxZoGV1Q?cluster=devnet

5.Rust客户端测试

Cargo.toml

[package]
name = "helloworld"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
solana-program = "1.18.9"
solana-sdk = "1.18.9"
solana-rpc-client = "1.18.9"
bs58 = "0.5.0"

lib.rs

use std::str::FromStr;

use solana_sdk::signature::Signer;
use solana_rpc_client::rpc_client;
use solana_sdk::signer::keypair;
use solana_sdk::transaction;
use solana_program::instruction;
use solana_program::pubkey;

const RPC_ADDR: &str = "https://api.devnet.solana.com";


fn main() {
    let helloworld = pubkey::Pubkey::from_str("BiEjWMFBfRCup21wQMcC7TxioLQZcnFxBXWKSxZoGV1Q").unwrap();
    
    let me = keypair::Keypair::from_base58_string("UtwQ...es0");
    println!("me is {}", me.pubkey());

    let client = rpc_client::RpcClient::new(RPC_ADDR);

    let account_metas = vec![
        instruction::AccountMeta::new(me.pubkey(), true),
    ];

    let instruction = instruction::Instruction::new_with_bytes(
        helloworld,
        "hello".as_bytes(),
        account_metas,
    );
    let ixs = vec![instruction];

    let latest_blockhash = client.get_latest_blockhash().unwrap();
    let sig = client.send_and_confirm_transaction(&transaction::Transaction::new_signed_with_payer(
        &ixs,
        Some(&me.pubkey()),
        &[&me],
        latest_blockhash,
    )).unwrap();

    println!("tx:{}", sig);
}

运行结果：

me is E3NAyseUZrgwSbYe2g47TuFJr5CxAeneK63mR4Ufbqhh
tx:W9aMuL8LGRwYRx2Xge4jj71i4ggcZVLMJairjn11T77qhZkg81YJ9HkKHW4x3ws5CPrXcTTxUmtveZkSPKyqXCR

查看浏览器：
https://solscan.io/tx/W9aMuL8LGRwYRx2Xge4jj71i4ggcZVLMJairjn11T77qhZkg81YJ9HkKHW4x3ws5CPrXcTTxUmtveZkSPKyqXCR?cluster=devnet