智能合约 Lover Wall --我的第一个包含数据库的简单的智能合约 (原创)

lome · 2018年03月03日 · 最后由 li 回复于 2018年04月29日 · 8810 次阅读
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目录

  1. 准备三步曲
    1. 本地环境
    2. 账户
    3. 基础文件生成
  2. 开始三步曲
    1. 结构编写
    2. 逻辑.cpp
    3. abi编写
  3. 成功三步曲
    1. 智能合约文件生成
    2. 智能合约发布
    3. 智能合约使用 # 准备三步曲 这一节我们要讲的是智能合约前期的准备工作。 ## 本地环境 本地环境部署这个就不在多说本论坛已经有很多的教程,这里列出链接: eos本地环境部署 在MacOS和Ubuntu上搭建EOS V2.0 ---爬过好多坑后的总结 除了部署本地环境以外,你还需要以下额外的操作: cd build make install 编译完以后就可以使用eos的插件了:eosc/eos-wallet/eoscpp/eosd eosd: 用来开启本地测试网络。 eosc: eos的命令行接口。 eoscpp: eos智能合约相关的功能,生成模版智能合约等等。 eos-wallet: eos钱包功能。

账户

新建一个或多个账户,部署智能合约,测试智能合约都能用得到。
本论坛有关账户的创建教程已经很完善,例如:
对eos的wallet和account简单关系的个人理解

基础文件生成

利用eoscpp可以快速的生成模版智能合约:

eoscpp -n <contract name>

执行完以后会在本地生成一个contract name的文件夹,里面包含智能合约需要的基础文件。执行截图如下:

eoscpp.png

会生成.cpp/.abi/.hpp三个必要的文件,文件中包含生成智能合约的基本内容。

开始三步曲

准备工作完成以后,开始写智能合约。

结构编写

/**
 *  @file
 *  @copyright defined in eos/LICENSE.txt
 */
#include <eoslib/eos.hpp>
#include <eoslib/db.hpp>

using namespace eosio; //使用eosio命名空间

namespace eos_fans{
        //数据库
    struct PACKED(love) {
        account_name    lover; //被表白的人
        account_name    author; //表白的人
        uint8_t                     times; //表白次数
    };

    //对谁表白action
    struct say {
        account_name    lover; //被表白的人
        account_name    author; //表白的人

    };

//table 参数依次为:该表所在的默认帐户名范围,代码帐户名称具有对此表的写入权限,表名,存储在每一行中的数据类型, 记录中存储的第一个字段的类型。
    using Lovers = eosio::table<N(eosfans),N(eosfans),N(loves),love,uint64_t>; 
}

逻辑.cpp

#include <eosfans.hpp>

using namespace eosio;

namespace eos_fans{
    //代码逻辑
    void say_love(const say& s) {
          //判断用户权限
        require_auth(s.author);
        love exited_love;
        bool love_exiting = Lovers::get(s.lover, exited_love, s.author);
          //判断是否已经存在,如果存在times加1,如果不存在则创建数据。
        if (love_exiting == true){
            exited_love.times += 1;
            Lovers::update(exited_love, s.author);

        }else{
            love love_to_say;
            love_to_say.lover = s.lover;
            love_to_say.author = s.author;
            love_to_say.times = 1;
            Lovers::store(love_to_say, s.author);
        }
    }
}

extern "C" {
    void init() {

    }

    /// The apply method implements the dispatch of events to this contract
    void apply( uint64_t code, uint64_t action ) {
        if ( code == N(eosfans) ){
            if (action == N(say)){
                eos_fans::say_love(current_message<eos_fans::say>());
            }
    }
}
}// extern "C"

abi编写

abi文件根据官网描述是可以通过eoscpp自动生成的,但是笔者尝试过,生成的文件的各个字段都是空的,所以这里就需要笔者自己编写,当然如果有人生成成功,可以告诉笔者正确生成方法,在这里提前感谢。
abi文件内容如下:

{
  "types": [],
  "structs": [{
        "name": "love", //所存储的数据类型
        "base": "",
        "fields": {
            "lover": "account_name",
            "author": "account_name",
            "times": "uint8"
        }
  },{
        "name": "say", //action
        "base": "",
        "fields": {
            "lover": "account_name",
            "author": "account_name"
        }
  }],
  "actions": [{
        "action_name": "say",
        "type": "say"
  }],
  "tables": [{
        "table_name": "loves", //数据表
        "type": "love",
        "index_type": "i64",
        "key_names": ["lover"], //索引字段
        "key_types": ["account_name"]
  }]
}

成功三步曲

智能合约写完以后,成功就近在眼前了。

智能合约文件生成

智能合约的各个组件编写完毕以后,下一步就是编译成.wast文件,eos有专门的工具:eoscpp,执行命令如下:

eoscpp -g eosfans.wast eosfans.cpp

执行完以后如果没有报错,就说明智能合约文件生成完毕,如果有错误可以根据错误对智能合约进行更改。

智能合约发布

智能合约文件生成完以后我们就要发布智能合约,命令如下:

eosc set contract eosfans eosfans.wast eosfans.abi

执行完以后你会看到智能合约生成的交易:

Reading WAST...
Assembling WASM...
Publishing contract...
{
  "transaction_id": "e59fac3876441bce2e65c6d20294523f6e597af71e0e7699b2d6d436a6f24444",
  "processed": {
    "ref_block_num": 64936,
    "ref_block_prefix": 4035039255,
    "expiration": "2018-03-03T07:59:50",
    "scope": [
      "eos",
      "lome"
    ],
    "signatures": [
      "1f030f69ef5e5f3c3f90835c04cd5ee9756a78ba22f7227ffee88dd33d3bc138450dd1e8caceb3c11bfe318389f772593f53f6103316d0c1650b514aab680a2c8d"
    ],
    "messages": [{
        "code": "eos",
        "type": "setcode",
        "authorization": [{
            "account": "lome",
            "permission": "active"
          }
        ],
        "data": {
          "account": "lome",
          "vm_type": 0,
          "vm_version": 0,
          "code": "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",
          "code_abi": {
            "types": [],
            "structs": [{
                "name": "love",
                "base": "",
                "fields": {
                  "lover": "account_name",
                  "author": "account_name",
                  "times": "uint8"
                }
              },{
                "name": "say",
                "base": "",
                "fields": {
                  "lover": "account_name",
                  "author": "account_name"
                }
              }
            ],
            "actions": [{
                "action_name": "say",
                "type": "say"
              }
            ],
            "tables": [{
                "table_name": "loves",
                "index_type": "i64",
                "key_names": [
                  "lover"
                ],
                "key_types": [
                  "account_name"
                ],
                "type": "love"
              }
            ]
          }
        },
        "hex_data": "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"
      }
    ],
    "output": [{
        "notify": [],
        "deferred_trxs": []
      }
    ]
  }
}

现在我们可以来看一下我们智能合约的table内容,通过如下命令察看:

eosc get table eosfans eosfans loves //table拥有者,智能合约名称, table名称

我们可以看到如下的显示:

eostable.png

智能合约使用

根据abi文件我们可以轻松使用智能合约,命令如下:

eosc push message eosfans say '{"lover": "eosfans", "author": "lome2"}' -S lome2 -p lome2@active

执行完以后我们可以看到交易的详情:

transaction.png

现在我们来看一下执行完几次后笔者的数据表,如下所示:

eosfanstable.png

该智能合约我已经发布在测试网络,合约名称为eosfans欢迎各位一起玩。

说明: 最近一直在学习智能合约其中遇到很多困难,譬如本地用的是2.0,官网的接口文档是3.0。这次使用的是2.0,以后将会把本地版本部署为3.0,这片文章以后若是在未说明的情况下所用的版本都为3.0。

共收到 8 条回复
strahe 将本帖设为了精华贴 03月26日 03:40

不错, 可以跟进下3.0, 应该不久后就会修复那些问题.

I used your code for hello contract, any idea to fix the following error?

./eosioc set contract currency ../../tools/hello/hello.wast ../../tools/hello/hello.abi
Reading WAST...
Assembling WASM...
Publishing contract...
1006357ms thread-0   main.cpp:981                  main                 ] Failed with error: Assert Exception (10)
status_code == 200: Error code 500
: {"code":500,"message":"Internal Service Error","error":{"code":10,"name":"assert_exception","message":"Assert Exception","details":"!\"unresolvable\": env.assert","stack_trace":[{"level":"error","file":"wavm.cpp","line":34,"method":"resolve","hostname":"","thread_name":"thread-0","timestamp":"2018-03-05T22:16:46.348"},{"level":"warn","file":"wavm.cpp","line":36,"method":"resolve","hostname":"","thread_name":"thread-0","timestamp":"2018-03-05T22:16:46.350"},{"level":"error","file":"wasm_interface.cpp","line":207,"method":"fetch_entry","hostname":"","thread_name":"thread-0","timestamp":"2018-03-05T22:16:46.352"},{"level":"warn","file":"apply_context.cpp","line":31,"method":"exec_one","hostname":"","thread_name":"thread-0","timestamp":"2018-03-05T22:16:46.352"},{"level":"warn","file":"chain_controller.cpp","line":256,"method":"push_transaction","hostname":"","thread_name":"thread-0","timestamp":"2018-03-05T22:16:46.353"}]}}

@orangetime

I used 2.0, but you used 3.0, so some things is different, i`ll deploy the 3.0 to try, please wait a moment.

哈哈,等你的3.0呢,加油哦~~~😝

li 回复

最近事情有点多,闲了会更新的。😁 😁

3.0的好久能更新?

3.0期待偶~~加油啊~

lome 心心念念的 Lover Wall 3.0 版本来了 (原创) 中提及了此贴 04月30日 00:37
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