该文档主要包括以下内容: * Wasm合约开发环境配置教程; * Wasm合约编译; * Wasm合约部署及调用;

方便用户对Wasm合约进行初步的了解,并快速掌握Wasm合约开发技巧.

1. 配置Wasm合约开发环境

获取最新稳定版的WASM合约发布包,并进行解压。

wget https://github.com/PlatONEnterprise/PlatONE-Go/releases/download/v0.9.0/BCWasm_linux_release.v0.9.0.tar.gz

# 进入BCWasm目录,然后定义路径:
cd BCWasm
export CONTRACTSSPACE=${PWD}

${CONTRACTSSPACE}目录下包含了合约编译所需的材料,合约源码目录为${CONTRACTSSPACE}/appContract

获取PlatONE最新稳定版的发布包,并进行解压。进入解压获得的PlatONE_linux目录,然后定义路径:

wget https://github.com/PlatONEnterprise/PlatONE-Go/releases/download/v0.9.0/PlatONE_linux_v0.9.0.tar.gz

tar -xzvf PlatONE_linux_v0.9.0.tar.gz

cd PlatONE_linux
export BIN_PATH=${PWD}/bin

⚠ 请确保 ${BIN_PATH}设置在当前的工作Shell,以让该环境变量生效。

2. 构建项目及编译合约

cd ${CONTRACTSSPACE}

# 1. 构建用户合约
./script/autoprojectForApp.sh  . my_contract

# 2. 构建工程
./script/autoprojectForApp.sh  .

# 3. 编译合约
cd build
make my_contract

2.1. 构建项目

第一步时,会在${CONTRACTSSPACE}/appContract下构建新的合约目录my_contract

第二步时,会在${CONTRACTSSPACE}下创建build,并编译合约。

此时,build目录下的结构如下所示

├── appContract
│   ├── appDemo
│   │   ├── appDemo.bc
│   │   ├── appDemo.cpp.abi.json ## 合约的abi文件
│   │   ├── appDemo.cpp.bc
│   │   ├── appDemo.s
│   │   ├── appDemo.wasm         ## 合约的wasm字节码
│   │   ├── appDemo.wast
│   │   ├── CMakeFiles
│   │   ├── cmake_install.cmake
│   │   └── Makefile
│   ├── CMakeFiles
│   ├── cmake_install.cmake
│   ├── Makefile
│   └── my_contract
│       ├── CMakeFiles
│       ├── cmake_install.cmake
│       ├── Makefile
│       ├── my_contract.cpp.abi.json ## 合约的abi文件
│       ├── my_contract.bc
│       ├── my_contract.cpp.bc
│       ├── my_contract.s
│       ├── my_contract.wasm
│       └── my_contract.wast
├── CMakeCache.txt
├── CMakeFiles
├── cmake_install.cmake
└── Makefile

合约文件会通过脚本autoprojectForApp.sh默认生成如下的源码,可以在此基础上编写自己的合约。

//auto create contract
#include <stdlib.h>
#include <string.h>
#include <string>
#include <bcwasm/bcwasm.hpp>

namespace demo {
class my_contract : public bcwasm::Contract
{
    public:
    my_contract(){}

    /// 实现父类: bcwasm::Contract 的虚函数
    /// 该函数在合约首次发布时执行,仅调用一次
    void init() 
    {
        bcwasm::println("init success...");
    }
    /// 定义Event.
    /// BCWASM_EVENT(eventName,arguments...)
    BCWASM_EVENT(setName,const char *)

    public:
    void setName(const char *msg)
    {
        // 定义状态变量
        bcwasm::setState("NAME_KEY",std::string(msg));
        // 日志输出
        // 事件返回
        BCWASM_EMIT_EVENT(setName,"std::string(msg)");
    }
    const char* getName() const 
    {
        std::string value;
        bcwasm::getState("NAME_KEY",value);
        // 读取合约数据并返回
        return value.c_str();
    }
};
}
// 此处定义的函数会生成ABI文件供外部调用
BCWASM_ABI(demo::my_contract,setName)
BCWASM_ABI(demo::my_contract,getName)

2.2. 编译合约

进入build目录并编译该合约

cd ${CONTRACTSSPACE}/build
make my_contract

生成文件如下

├build/ 
├-appContact/
│   └── my_contract
│       ├── CMakeFiles
│       ├── cmake_install.cmake
│       ├── Makefile
│       ├── my_contract.cpp.abi.json ## 合约的abi文件
│       ├── my_contract.bc
│       ├── my_contract.cpp.bc
│       ├── my_contract.s
│       ├── my_contract.wasm
│       └── my_contract.wast

主要文件简介:

其中,发布合约时需要用到的文件为my_contract.wast和my_contract.cpp.abi.json。

3. 部署及调用合约

3.1. 生成合约部署账户

cd ${CONTRACTSSPACE}/build
../script/create_accout.sh --ip 127.0.0.1 --rpc_port 6791

该命令会创建一个新的账户,创建时需要输入一个账户密码,方便后续解锁。

除了新生成一个账户,该命令还会在当前目录创建一个config.json文件,该文件在调用合约时会用到。该文件记录节点的ip端口以及发送交易的账号。

运行结果如下:

nodeid: 127.0.0.1
rpc_port: 6791

###########################################
####       Create an account           ####
###########################################

Input account passphrase.
passphrase: your_phrase
--output{"jsonrpc":"2.0","id":1,"result":"0x08e7988e60ab5aa49d1f7aa9435ac91b9fcf772c"} --output
New account: 0x08e7988e60ab5aa49d1f7aa9435ac91b9fcf772c
{"jsonrpc":"2.0","id":1,"result":true}
127.0.0.1:6791

 Create config.json for contract-deploy

{
  "url":"http://127.0.0.1:6791",
  "gas":"0x0",
  "gasPrice":"0x0",
  "from":"0x08e7988e60ab5aa49d1f7aa9435ac91b9fcf772c"
}

配置文件字段简述:

长时间没用使用账户发送过交易,或者节点重启后,账户会被锁定,不能发送交易。需要使用如下命令,重新为账户解锁。

../script/unlock_account.sh \
             --account 0x08e7988e60ab5aa49d1f7aa9435ac91b9fcf772c \
            --phrase "your_phrase" \
            --ip 127.0.0.1 \
            --rpc_port 6791

3.2. 部署合约

cd ${CONTRACTSSPACE}/build

# ctool是用来部署合约及发送交易的工具。
cp  ${BIN_PATH}/ctool  .

# 部署合约
./ctool deploy --abi appContract/my_contract/my_contract.cpp.abi.json --code appContract/my_contract/my_contract.wasm --config ./config.json

结果:

trasaction hash: 0x2f3a868d8ceb60804a830e5fc35611e3ae22ccb6ef298830acd84aba41f6dd99
contract address: 0x2ee8d0545ebd20f9a992ff54cb0f21a153539206

ctool工具使用方式主要有以下两种:

# 合约部署
./ctool                                                     \
    deploy                                                  \
    --abi   contract.cpp.abi.json                           \
    --code  contract.wasm                                   \
    --config ./config.json

# 合约调用
./ctool                                                     \
    invoke                                                  \
    --abi   contract.cpp.abi.json                           \
    --addr  "合约地址: 0x1234"                               \
    --config ./config.json                                  \
    --func  "方法名字"                                       \
    --param  "第1个参数"                                     \
    --param  "第2个参数"                                     

3.3. 调用合约

调用合约的setName方法

#地址需要改成上节生成的地址

./ctool invoke --addr 0x2ee8d0545ebd20f9a992ff54cb0f21a153539206 --abi appContract/my_contract/my_contract.cpp.abi.json   --config ./config.json  --func "setName" --param "wxbc"  

 request json data:[{"from":"0x32ab0a20b589f40c7e3d6ee485a2404bb7269f87","to":"0x2ee8d0545ebd20f9a992ff54cb0f21a153539206","gas":"0x0","gasPrice":"0x0","value":"","data":"0xdb8800000000000000028c696e766f6b654e6f746966798477786263","txType":2}] 
 response json:{"jsonrpc":"2.0","id":1,"result":"0xeb3680c65b393952a07ec590cef7b19fc87877a9fbb70c8e16797a97ed4cfaeb"}

调用合约的getName方法:

#地址需要改成上节生成的地址

./ctool invoke --addr 0x2ee8d0545ebd20f9a992ff54cb0f21a153539206 --abi appContract/my_contract/my_contract.cpp.abi.json   --config ./config.json  --func getName

request json data:[{"from":"0x32ab0a20b589f40c7e3d6ee485a2404bb7269f87","to":"0x2ee8d0545ebd20f9a992ff54cb0f21a153539206","gas":"0x0","gasPrice":"0x0","value":"","data":"0xd1880000000000000002876765744e616d65","txType":2},"latest"] 
response json:{"jsonrpc":"2.0","id":1,"result":"0x000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000047778626300000000000000000000000000000000000000000000000000000000"}

result: wxbc

4. 通过console与节点交互

4.1. 节点交互

cd ${BIN_PATH}

./platone attach http://127.0.0.1:6791

Welcome to the PlatONE JavaScript console!

instance: PlatONEnetwork/platone/v0.2.0-stable-1b13ff73/linux-amd64/go1.12.4
coinbase: 0x938c231429f5ab34244618fe0dc7380e319b470e
at block: 1557 (Tue,18 Jun 2019 16:29:12 CST)
 datadir: /home/gexin/PlatONE-Workspace/chain/PlatONE_linux/data/node-1
 modules: admin:1.0 eth:1.0 net:1.0 personal:1.0 rpc:1.0 web3:1.0

> 

通过上面命令可以与节点交互,用于查询相关信息

4.2. 查询交易receipt

#交易哈希值改成上节生成的
> eth.getTransactionReceipt("0x2f3a868d8ceb60804a830e5fc35611e3ae22ccb6ef298830acd84aba41f6dd99")

结果如下:

{
  blockHash: "0x3f1e326f4b122efb26e9da417daff97dbb403c714d3324e8020ddce04b88617a",
  blockNumber: 236,
  contractAddress: "0x2ee8d0545ebd20f9a992ff54cb0f21a153539206",
  cumulativeGasUsed: 1996535,
  from: "0x32ab0a20b589f40c7e3d6ee485a2404bb7269f87",
  gasUsed: 1996535,
  logs: [],
  logsBloom: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
  status: "0x1",
  to: null,
  transactionHash: "0x2f3a868d8ceb60804a830e5fc35611e3ae22ccb6ef298830acd84aba41f6dd99",
  transactionIndex: 0
}