本章节利用EOS的智能合约实现了简单的投票，功能包括
- 创建投票
- 发起投票
- 投票／委托投票
- 投票的winner提案
与以太坊的
https://solidity.readthedocs.io/en/latest/solidity-by-example.html#voting
功能类似，大家可以比较下Ethereum的Solidity版本与EOS的C++版本语法上的差别。
本文参考了https://www.cnblogs.com/Jogging/p/ballot.html，针对最新的EOS版本（1.0.5）修改了部分合约代码以及步骤。
创建合约
eos@mybc:~$ eosiocpp -n ballot
created ballot from skeleton
eos@mybc:~$ cd ballot/
eos@mybc:~/ballot$ ll
total 16
drwxr-xr-x 2 eos eos 4096 Jun 20 14:43 ./
drwxr-xr-x 8 eos eos 4096 Jun 20 14:43 ../
-rw-rw-r-- 1 eos eos 275 Jun 20 14:43 ballot.cpp
-rw-rw-r-- 1 eos eos 92 Jun 20 14:43 ballot.hpp
eos@mybc:~/ballot$
修改ballot.hpp
/**
* @file
* @copyright defined in eos/LICENSE.txt
*/
#include
#include
namespace eosio {
using std::string;
class ballot : public eosio::contract
{
public:
using contract::contract;
ballot(account_name self) : contract(self) {}
// 投票发起人接口
void addposposal(string posposal_name); // 初始化投票提案
void addvoter(account_name voter_name, uint64_t weight = 1); // 初始化投票人
// 普通选民接口
void delegate(account_name voter, account_name delegate_to); // 委托投票（跟随投票）
void vote(account_name voter, string proposal); // 投票给某个提议
void winproposal(); // 返回投票数最多的提议
void allproposal(); // 返回全部提案投票状态
private:
// 定义投票人
struct voter
{
account_name account; // 投票人
uint64_t weight; // 权重
bool voted; // 如果值为true，代表这个投票人已经投过票
uint64_t delegate_account; // 委托投票人地址
string pos_name; // 投票提案名
uint64_t primary_key() const { return account; }
EOSLIB_SERIALIZE(voter, (account)(weight)(voted)(delegate_account)(pos_name))
};
// 提案的数据结构
struct posposal
{
string name; // 提案的名称
uint64_t voteCount; // 提议接受的投票数
uint64_t primary_key() const { return eosio::string_to_name(name.c_str()); }
EOSLIB_SERIALIZE(posposal, (name)(voteCount))
};
typedef eosio::multi_index voter_index;
typedef eosio::multi_index posposal_index;
};
}
修改ballot.cpp
#include
#include "ballot.hpp"
namespace eosio {
// 投票发起人接口
void ballot::addposposal(string posposal_name) // 初始化投票提案
{
require_auth(_self);
posposal_index posposals(_self, _self);
auto it = posposals.find(eosio::string_to_name(posposal_name.c_str()));
eosio_assert(it == posposals.end(), "posposal exist");
posposals.emplace(_self, [&](auto &a) {
a.name = posposal_name;
a.voteCount = 0;
});
}
void ballot::addvoter(account_name voter_name, uint64_t weight /* =1 */) // 初始化投票人
{
require_auth(_self);
eosio_assert(weight > 0, "must positive weight");
voter_index voters(_self, _self);
auto it = voters.find(voter_name);
eosio_assert(it == voters.end(), "voter exist");
voters.emplace(_self, [&](auto &a) {
a.account = voter_name;
a.weight = weight;
a.voted = false;
a.delegate_account = 0;
a.pos_name = "";
});
}
// 普通选民接口
void ballot::delegate(account_name voter, account_name delegate_to) // 委托投票（跟随投票）
{
require_auth(voter);
voter_index voters(_self, _self);
auto vit = voters.find(voter);
eosio_assert(vit->voted == false, "is voted");
eosio_assert(vit != voters.end(), "voter not exist");
auto it = voters.find(delegate_to);
eosio_assert(it != voters.end(), "delegate_to not exist");
while (it != voters.end() && it->delegate_account != 0 && it->delegate_account != voter)
it = voters.find(it->delegate_account);
eosio_assert(it != voters.end(), "delegate obj not exist");
eosio_assert(it->account != voter, "not delegate self");
if (it->voted)
{
vote(voter, it->pos_name);
}
else
{
voters.modify(it, _self, [&](auto &a) {
a.weight += vit->weight;
});
voters.modify(vit, _self, [&](auto &a) {
a.voted = true;
});
}
}
void ballot::vote(account_name voter, string proposal) // 投票给某个提议
{
require_auth(voter);
posposal_index posposals(_self, _self);
auto it = posposals.find(eosio::string_to_name(proposal.c_str()));
eosio_assert(it != posposals.end(), "posposal not exist");
voter_index voters(_self, _self);
auto vit = voters.find(voter);
eosio_assert(vit->voted == false, "is voted");
eosio_assert(vit != voters.end(), "voter not exist");
voters.modify(vit, _self, [&](auto &a) {
a.voted = true;
a.pos_name = proposal;
});
posposals.modify(it, _self, [&](auto &a) {
a.voteCount += vit->weight;
});
}
void ballot::winproposal() // 返回投票数最多的提议
{
posposal_index posposals(_self, _self);
auto win = posposal();
uint64_t max = 0;
for (auto it : posposals)
{
if (it.voteCount > max)
{
max = it.voteCount;
win = it;
}
}
if (max > 0)
{
eosio::print("win posposal is: ", win.name.c_str(), "vote count", win.voteCount, "\n");
}
else
{
eosio::print("not vote", "\n");
}
}
void ballot::allproposal() // 返回全部提案投票状态
{
posposal_index posposals(_self, _self);
uint64_t idx = 0;
for (auto it : posposals)
{
eosio::print(" posposal ", idx, ":", it.name.c_str(), ", vote count:", it.voteCount, "\n");
}
}
} /// namespace eosio
EOSIO_ABI(eosio::ballot, (addposposal)(addvoter)(delegate)(vote)(winproposal)(allproposal))
编译合约
EOS智能合约部署的时候只认wast格式，可以通过eosiocpp命令(需要编译eos)编译合约
eos@mybc:~/ballot$ eosiocpp -o ballot.wast ballot.cpp
eos@mybc:~/ballot$ eosiocpp -g ballot.abi ballot.cpp
3083077ms thread-0 abi_generator.hpp:68 ricardian_contracts ] Warning, no ricardian clauses found for Ballot
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for addposposal
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for addvoter
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for delegate
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for vote
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for winproposal
3083077ms thread-0 abi_generator.hpp:75 ricardian_contracts ] Warning, no ricardian contract found for allproposal
Generated ballot.abi ...
eos@mybc:~/ballot$ ll
total 244
drwxr-xr-x 2 eos eos 4096 Jun 20 14:51 ./
drwxr-xr-x 8 eos eos 4096 Jun 20 14:48 ../
-rw-rw-r-- 1 eos eos 1760 Jun 20 14:51 ballot.abi
-rw-rw-r-- 1 eos eos 3266 Jun 20 14:48 ballot.cpp
-rw-rw-r-- 1 eos eos 1769 Jun 20 14:47 ballot.hpp
-rw-rw-r-- 1 eos eos 18200 Jun 20 14:51 ballot.wasm
-rw-rw-r-- 1 eos eos 206171 Jun 20 14:51 ballot.wast
eos@mybc:~/ballot$
环境准备
创建合约账号以及投票账号
注意！默认账号eosio需要导入私钥，否则会报错Error 3090003: provided keys, permissions, and delays do not satisfy declared authorizations
eos@mybc:~/contracts/ballot$ cleos create key
Private key: 5KPysXNbzLq7T7pumusTkqHcVancsJmo8dLMWDuAVDyfkhVA5HZ
Public key: EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos wallet create -n gxk
Creating wallet: gxk
Save password to use in the future to unlock this wallet.
Without password imported keys will not be retrievable.
"PW5JKsVdSDJ9f3vnwNpcEev9JPnqpTyDDAnwcMcnJ4W1W1Y2dx112"
eos@mybc:~/contracts/ballot$ cleos wallet import 5KPysXNbzLq7T7pumusTkqHcVancsJmo8dLMWDuAVDyfkhVA5HZ -n gxk
imported private key for: EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$
eos@mybc:~/contracts/ballot$ cleos create account eosio acc1 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
Error 3090003: provided keys, permissions, and delays do not satisfy declared authorizations
Ensure that you have the related private keys inside your wallet and your wallet is unlocked.
eos@mybc:~/contracts/ballot$ cleos wallet import 5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3 -n gxk
imported private key for: EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV
eos@mybc:~/contracts/ballot$ cleos create account eosio acc1 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
executed transaction: 06abb464a28cf7d81598896f7b46504314ccb0defbdee052e7382f3b4ef3c6c9 200 bytes 222 us
# eosio <= eosio::newaccount {"creator":"eosio","name":"acc1","owner":{"threshold":1,"keys":[{"key":"EOS51R5G76bu9rK7g7WqAjH3j9Wr...
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~/contracts/ballot$ cleos create account eosio acc1 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos create account eosio acc2 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos create account eosio acc3 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos create account eosio acc4 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos create account eosio acc5 EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos create account eosio accballot EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
eos@mybc:~/contracts/ballot$ cleos get accounts EOS51R5G76bu9rK7g7WqAjH3j9WrBfEmiz5NPaV13eCVnHc9V2NXg
{
"account_names": [
"acc1",
"acc2",
"acc3",
"acc4",
"acc5",
"accballot"
]
}
部署智能合约
首先需要把合约目录拷贝到docker的挂载点, 设置成本地路径对于docker来说是无效的，会报no wast file found，需要拷贝文件到docker能访问的目录
Reading WAST/WASM from contracts/ballot/ballot.wast...
1995557ms thread-0 main.cpp:2712 main ] Failed with error: Assert Exception (10)
!wast.empty(): no wast file found contracts/ballot/ballot.wast
cp -r ballot /opt/eosio/data/contracts/
开始正式部署
eos@mybc:~/contracts/ballot$
eos@mybc:~$ cleos set contract accballot /opt/eosio/bin/data-dir/contracts/ballot
Reading WAST/WASM from /opt/eosio/bin/data-dir/contracts/ballot/ballot.wasm...
Using already assembled WASM...
Publishing contract...
executed transaction: d76b4c9ff65b9c49c7412a2ccd2fa152241d65d92f33b8e6230df0959de98648 7872 bytes 1086 us
# eosio <= eosio::setcode {"account":"accballot","vmtype":0,"vmversion":0,"code":"0061736d01000000017a1460027f7f0060037f7e7e00...
# eosio <= eosio::setabi {"account":"accballot","abi":"0e656f73696f3a3a6162692f312e3000060b616464706f73706f73616c00010d706f73...
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$
增加投票选项
eos@mybc:~$ cleos push action accballot addposposal '["baidu"]' -p accballot
executed transaction: 913a8b376bc4ac49e320819bd9a1ec35e2d7a9ca280b5fe11d8ddd9b0d93be75 104 bytes 442 us
# accballot <= accballot::addposposal {"posposal_name":"baidu"}
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$ cleos push action accballot addposposal '["alibaba"]' -p accballot
eos@mybc:~$ cleos push action accballot addposposal '["163"]' -p accballot
eos@mybc:~$ cleos push action accballot addposposal '["360"]' -p accballot
eos@mybc:~$ cleos push action accballot addposposal '["qq"]' -p accballot
eos@mybc:~$ cleos push action accballot addposposal '["yy"]' -p accballot
添加投票人
eos@mybc:~$ cleos push action accballot addvoter '["acc1",1]' -p accballot
executed transaction: 172e42446d8379fecc430ae5a2fe76a691e5f1020be4fba12fdb49803b57f517 112 bytes 330 us
# accballot <= accballot::addvoter {"voter_name":"acc1","weight":1}
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$ cleos push action accballot addvoter '["acc2",1]' -p accballot
eos@mybc:~$ cleos push action accballot addvoter '["acc3",1]' -p accballot
eos@mybc:~$ cleos push action accballot addvoter '["acc4",1]' -p accballot
eos@mybc:~$ cleos push action accballot addvoter '["acc5",1]' -p accballot
开始投票
eos@mybc:~$ cleos push action accballot allproposal '[]' -p acc1
executed transaction: c80fc27e5d73183473c802e7485b2bbccadecf320d574755b8ddd338bc63db74 96 bytes 780 us
# accballot <= accballot::allproposal {}
>> posposal 0:163vote count0
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$ cleos push action accballot vote '["acc1","qq"]' -p acc1
executed transaction: c00f730ed13457e2b353cc64b8c9a4945521bbdf6b8f55290d6d2cfc9a516374 104 bytes 545 us
# accballot <= accballot::vote {"voter":"acc1","proposal":"qq"}
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$ cleos push action accballot vote '["acc2","qq"]' -p acc2
eos@mybc:~$ cleos push action accballot vote '["acc3","163"]' -p acc3
eos@mybc:~$ cleos push action accballot vote '["acc4","qq"]' -p acc4
eos@mybc:~$ cleos push action accballot delegate '["acc5","acc3"]' -p acc5
投票结果
eos@mybc:~$ cleos push action accballot winproposal '[]' -p acc1
executed transaction: ceadf4c99152ba1ce66c6a41d4d0249a34f97c2d23ad4ee8a3ec2ba0b125053c 96 bytes 705 us
# accballot <= accballot::winproposal {}
>> win posposal is: qqvote count3
warning: transaction executed locally, but may not be confirmed by the network yet
eos@mybc:~$
nodeosd节点会打印如下日志（需要在config.ini中开启contrac-console = true）
这里合约中的idx变量没有递增，所以posposal都是0，大家勿怪
1168829ms thread-0 apply_context.cpp:28 print_debug ]
[(accballot,allproposal)->accballot]: CONSOLE OUTPUT BEGIN =====================
posposal 0:163, vote count:2
posposal 0:360, vote count:0
posposal 0:alibaba, vote count:0
posposal 0:baidu, vote count:0
posposal 0:qq, vote count:3
posposal 0:yy, vote count:0
[(accballot,allproposal)->accballot]: CONSOLE OUTPUT END =====================