EOS博彩合约设计
集中博彩游戏合约设计
一、功能接口
1. 质押deposit
由用户发起,用户将个人账户中token质押给平台,从而可以进入平台去参与平台活动。
2. 赎回withdraw
由用户发起,在用户结束平台活动需要离开时,发起赎回曾质押给平台的token到个人账户。
3. 开启一期下注openbet
由平台发起,平台启动一期下注,玩家可以参与下注。
4. 结束一期下注 closurebet
由平台发起,平台关闭一期下注,所以玩家的下注被锁定。
5. 下注offerbet
由用户发起,用户参与平台开启的下注,需要在一期下注开启之后执行。
6. 取消下注canneloffer
由用户发起,用户取消曾参与的下注,需要在该期下注结束之前执行。
7. 开奖reveal
由平台发起,平台在一期下注上进行结果操作。
二、数据存储
1. 质押赎回账户表account_index
个人账户token质押给平台和从平台赎回token需要一个账户表来管理个人账户token信息,账户表数据结构如下:
a. 个人账户名称
b. 资产额
2. 下注期数记录表g_bet_index
游戏从第1期开始,随后每开启一期游戏,期数自动加1,游戏期数记录表记录了总的下注期数,同时也记录了当前正在进行或者要开启的下一期下注的期数,下注期数记录表结构如下:
a. 记录id
b. 当前正在进行的下注期数
c. 当前正在进行的下注期名称
d. 当前下注开启关闭状态
e. 当前下注结算状态
3. 下注记录表bet_index
在一期下注开启时间窗口,平台用户可以自由下注以及取消下注,下注记录表则记录了用户的下注情况,下注记录表数据结构如下:
a. 记录id
b. 下注期数
c. 个人账户名称
d. 下注资产额
e. 下注信息
三、接口实现设计
a. 质押赎回
1. 用户发起质押操作,参数包括质押资产额
2. 从user账户转账token到dice账户,dice.xxx合约将调用eosio.token的transfer action执行转账操作,将user个人账户中token转账到合约账户dice
3. 修改质押赎回账户表,记录user个人用户的质押信息,添加新记录或者修改记录
4. 用户发起赎回操作
5. 从dice账户转账token到user个人账户,dice.xxx合约将调用eosio.token的transfer action执行转账
6. 修改质押赎回账户表,修改user个人用户的质押信息,修改记录或者删除记录
b. 开启下注、结束下注以及开奖
1. 平台发起一次openbet
2. 检查新一期下注是否合法,检查是否有正在进行的下注,如果没有则当前期数+1,同时下注开启
3. 平台发起一次closurebet
4. 检查关闭的下注是否合法,检查是否有正在进行的下注,如果有,则关闭下注
5. 平台发起一次开奖
6. 计算改期开奖结果,计算池中各用户的下注信息并给出各个用户的开奖结果
7. 开奖结果兑现,将开奖结果兑现到各用户的质押上
c. 下注及取消下注
1. 用户发起下注,参数包括下注资产额、下注信息
2. 检查该期下注是否在开放窗口期,如果不在开放窗口期则不能下注
3. 修改用户质押资产额
4. 修改用户下注资产额以及下注信息
5. 用户发起取消下注
6. 检查该期下注是否在开放窗口期,如果不在开放窗口期则不能取消下注
7. 修改用户下注资产额及下注信息
8. 修改用户质押资产额
四、部署合约
1. 创建合约账户
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 create account eosio dice.xxx EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV
2. 部署合约
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 set contract dice.xxx /home/kingnet/tangy/eos/mycontracts/dice.xxx
五、平台接口使用
平台接口需要合约账户
1. 开启下注
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx openbet '{}' -p dice.xxx
2. 关闭下注
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx closurebet '{}' -p dice.xxx
3. 开奖
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx reveal '{}' -p dice.xxx
六、用户接口使用
1. 质押
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx deposit '{"from":"alice", "quantity":"100.0000 EOS"}' -p alice
2. 赎回
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx withdraw '{"to":"alice", "quantity":"100.0000 EOS"}' -p alice
以下用户接口需要在下注开启窗口才能被执行
3. 用户下注
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx offerbet '{"bet":"10.0000 EOS", "player":"alice","info":0}' -p alice
4. 取消下注
cleos --wallet-url http://localhost:9800 --url http://localhost:9800 push action dice.xxx canceloffer '{"player":"alice"}' -p alice
七、合约代码
/**
- @file
 - @copyright defined in eos/LICENSE.txt
*/ 
include
include
include
include <eosiolib/eosio.hpp>
include <eosiolib/asset.hpp>
include <eosiolib/contract.hpp>
include <eosiolib/crypto.h>
using eosio::key256;
using eosio::indexed_by;
using eosio::const_mem_fun;
using eosio::asset;
using eosio::permission_level;
using eosio::action;
using eosio::print;
using eosio::name;
class dice : public eosio::contract {
public:
dice(account_name self) : eosio::contract(self),
bets(_self, _self),
gbet(_self, _self),
accounts(_self, _self) {
}
  //@abi action
  void offerbet(const asset& bet, account_name player, const uint64_t betinfo) {
     eosio_assert( bet.symbol == S(4,EOS) , "only EOS token allowed" );
     eosio_assert( bet.is_valid(), "invalid bet" );
     eosio_assert( bet.amount > 0, "must bet positive quantity" );
     //
     require_auth( player );
     auto cur_player_itr = accounts.find( player );
     eosio_assert(cur_player_itr != accounts.end(), "unknown account");
     eosio_assert(cur_player_itr->balance >= bet, "insufficient balance");
     auto cur_gbet_itr = gbet.begin();
     eosio_assert(cur_gbet_itr != gbet.end(), "bet is not build");
     eosio_assert(cur_gbet_itr->open == 1, "bet is not open");
     eosio_assert(cur_gbet_itr->reveal == 0, "bet is revealed");
     uint64_t betid = cur_gbet_itr->betid;
     uint64_t exist_bet = false;
	 auto bybetid_index = bets.template get_index<N(bybetid)>();
	 auto cur_bets_itr = bybetid_index.find(betid);
	 while(cur_bets_itr != bybetid_index.end() && cur_bets_itr->betid == betid) {
		 if(cur_bets_itr->owner == player) {
			 exist_bet = true;
			 break;
		 }
		 cur_bets_itr ++;
	 }
     eosio_assert(exist_bet == false, "bet is done");
     // Store new offer
	 auto new_bet_itr = bets.emplace(_self, [&](auto& rbet){
		rbet.id          = bets.available_primary_key();
		rbet.balance     = bet;
		rbet.owner       = player;
		rbet.betid       = betid;
		rbet.info        = betinfo;
	 });
	 // Update player's accounts
	 accounts.modify( cur_player_itr, 0, [&](auto& acnt) {
	    eosio_assert( acnt.balance >= bet, "insufficient balance" );
	    acnt.balance -= bet;
	 });
  }
  //@abi action
  void canceloffer(account_name player) {
	  //
	  require_auth( player );
      auto cur_gbet_itr = gbet.begin();
      eosio_assert(cur_gbet_itr != gbet.end(), "bet is not build");
      eosio_assert(cur_gbet_itr->open == 1, "bet is closed");
      eosio_assert(cur_gbet_itr->reveal == 0, "bet is revealed");
      uint64_t betid = cur_gbet_itr->betid;
      uint64_t exist_bet = false;
	  auto bybetid_index = bets.template get_index<N(bybetid)>();
	  auto cur_bets_itr = bybetid_index.find(betid);
	  while(cur_bets_itr != bybetid_index.end() && cur_bets_itr->betid == betid) {
		 if(cur_bets_itr->owner == player) {
			 exist_bet = true;
			 break;
		 }
		cur_bets_itr ++;
	  }
      eosio_assert(exist_bet == true, "no bet");
	  // Update player's accounts
      auto cur_player_itr = accounts.find( player );
      if( cur_player_itr == accounts.end() ) {
    	cur_player_itr = accounts.emplace(_self, [&](auto& acnt){
		  acnt.owner = player;
	    });
      }
	  accounts.modify( cur_player_itr, 0, [&](auto& acnt) {
		 acnt.balance += cur_bets_itr->balance;
	  });
	  bybetid_index.erase(cur_bets_itr);
      //bets.erase(cur_bet_itr);
  }
  //@abi action
  void openbet() {
	  //
	  require_auth(_self);
      // Create global bet counter if not exists
      auto cur_gbet_itr = gbet.begin();
      if( cur_gbet_itr == gbet.end() ) {
    	  cur_gbet_itr = gbet.emplace(_self, [&](auto& g_bet){
    		 g_bet.id = gbet.available_primary_key();
        	 g_bet.betid = 0;
        	 g_bet.open = 0;
        	 g_bet.reveal = 1;
         });
      }
      eosio_assert(cur_gbet_itr != gbet.end(), "bet is not build");
      eosio_assert(cur_gbet_itr->open == 0, "bet is opened");
      eosio_assert(cur_gbet_itr->reveal == 1, "bet is not reveal");
      // Increment global bet counter
      gbet.modify(cur_gbet_itr, 0, [&](auto& g_bet){
    	  g_bet.betid++;
    	  g_bet.open = 1;
    	  g_bet.reveal = 0;
      });
  }
  //@abi action
  void closurebet() {
	  //
	  require_auth(_self);
      auto cur_gbet_itr = gbet.begin();
      eosio_assert(cur_gbet_itr != gbet.end(), "bet is not build");
      eosio_assert(cur_gbet_itr->open == 1, "bet is closure");
      eosio_assert(cur_gbet_itr->reveal == 0, "reveal is done");
      // udpate global bet status
      gbet.modify(cur_gbet_itr, 0, [&](auto& g_bet){
    	  g_bet.open = 0;
      });
  }
  //@abi action
  void reveal() {
	  //
	  require_auth(_self);
      auto cur_gbet_itr = gbet.begin();
      eosio_assert(cur_gbet_itr != gbet.end(), "bet is not build");
      eosio_assert(cur_gbet_itr->open == 0, "bet is open");
      eosio_assert(cur_gbet_itr->reveal == 0, "reveal is done");
      //
      uint64_t bet_result = 0;
      uint64_t betid = cur_gbet_itr->betid;
      //
      {
          uint32_t t_now = now();
          checksum256 hash;
          sha256((char*)(&t_now), sizeof(uint32_t), &hash);
          bet_result = (hash.hash[15]) % 2;
      }
	  //
      asset total_balance;
      asset win_balance;
	  auto bybetid_index = bets.template get_index<N(bybetid)>();
	  auto cur_bets_itr = bybetid_index.find(betid);
	  while(cur_bets_itr != bybetid_index.end() && cur_bets_itr->betid == betid) {
		  total_balance += cur_bets_itr->balance;
		  if(cur_bets_itr->info == bet_result)
			  win_balance += cur_bets_itr->balance;
		  cur_bets_itr++;
	  }
	  if(win_balance.amount == 0) {
		 bybetid_index = bets.template get_index<N(bybetid)>();
		 cur_bets_itr = bybetid_index.find(betid);
		 while(cur_bets_itr != bybetid_index.end() && cur_bets_itr->betid == betid) {
		    auto use_balance = cur_bets_itr->balance;
		    auto cur_player_itr = accounts.find( cur_bets_itr->owner );
		    if( cur_player_itr == accounts.end() ) {
		       cur_player_itr = accounts.emplace(_self, [&](auto& acnt){
			   acnt.owner = cur_bets_itr->owner;
		       });
		    }
		    accounts.modify( cur_player_itr, 0, [&]( auto& acnt ) {
		      acnt.balance += use_balance;
		    });
		    cur_bets_itr ++;
		 }
	  } else {
		  bybetid_index = bets.template get_index<N(bybetid)>();
		  cur_bets_itr = bybetid_index.find(betid);
		  while(cur_bets_itr != bybetid_index.end() && cur_bets_itr->betid == betid) {
			  if(cur_bets_itr->info == bet_result) {
				  //auto use_balance = (cur_bets_itr->balance / win_balance) * total_balance;
				  auto use_balance = (cur_bets_itr->balance * total_balance.amount) / win_balance.amount;
				  auto cur_player_itr = accounts.find( cur_bets_itr->owner );
				  if( cur_player_itr == accounts.end() ) {
					  cur_player_itr = accounts.emplace(_self, [&](auto& acnt){
						acnt.owner = cur_bets_itr->owner;
					 });
				  }
				  accounts.modify( cur_player_itr, 0, [&]( auto& acnt ) {
					 acnt.balance += use_balance;
				  });
			  }
			  cur_bets_itr ++;
		  }
	  }
      // udpate global bet status
      gbet.modify(cur_gbet_itr, 0, [&](auto& g_bet){
    	 g_bet.reveal = 1;
      });
  }
  //@abi action
  void deposit( const account_name from, const asset& quantity ) {
	 require_auth( from );
     eosio_assert( quantity.is_valid(), "invalid quantity" );
     eosio_assert( quantity.amount > 0, "must deposit positive quantity" );
     auto itr = accounts.find(from);
     if( itr == accounts.end() ) {
        itr = accounts.emplace(_self, [&](auto& acnt){
           acnt.owner = from;
        });
     }
     action(
        permission_level{ from, N(active) },
        N(eosio.token), N(transfer),
        std::make_tuple(from, _self, quantity, std::string(""))
     ).send();
     accounts.modify( itr, 0, [&]( auto& acnt ) {
        acnt.balance += quantity;
     });
  }
  //@abi action
  void withdraw( const account_name to, const asset& quantity ) {
     require_auth( to );
     eosio_assert( quantity.is_valid(), "invalid quantity" );
     eosio_assert( quantity.amount > 0, "must withdraw positive quantity" );
     auto itr = accounts.find( to );
     eosio_assert(itr != accounts.end(), "unknown account");
     accounts.modify( itr, 0, [&]( auto& acnt ) {
        eosio_assert( acnt.balance >= quantity, "insufficient balance" );
        acnt.balance -= quantity;
     });
     action(
        permission_level{ _self, N(active) },
        N(eosio.token), N(transfer),
        std::make_tuple(_self, to, quantity, std::string(""))
     ).send();
     if( itr->is_empty() ) {
        accounts.erase(itr);
     }
  }
  //@abi action
  void reset() {
	  //
     require_auth( _self );
     auto cur_gbet_itr = gbet.begin();
     while(cur_gbet_itr != gbet.end()) {
    	 cur_gbet_itr = gbet.erase(cur_gbet_itr);
     }
     auto cur_bet_itr = bets.begin();
     while(cur_bet_itr != bets.end()) {
    	 cur_bet_itr = bets.erase(cur_bet_itr);
     }
  }
private:
//@abi table bet i64
struct bet {
uint64_t          id;
account_name      owner;
asset             balance;
uint64_t          betid;
uint64_t          info;
     uint64_t primary_key()const { return id; }
     uint64_t by_betid()const { return betid; }
     account_name by_owner() const { return owner; }
     EOSLIB_SERIALIZE( bet, (id)(owner)(balance)(betid)(info) )
  };
  typedef eosio::multi_index< N(bet), bet,
     indexed_by< N(bybetid), const_mem_fun<bet, uint64_t, &bet::by_betid > >,
     indexed_by< N(byowner), const_mem_fun<bet, account_name, &bet::by_owner > > > bet_index;
  //@abi table gbet i64
  struct gbet {
     uint64_t id;
     uint64_t betid;
     uint64_t betname;
     uint64_t open = 0;
     uint64_t reveal = 0;
     uint64_t primary_key()const { return id; }
     EOSLIB_SERIALIZE( gbet, (id)(betid)(betname)(open)(reveal) )
  };
  typedef eosio::multi_index< N(gbet), gbet> gbet_index;
  //@abi table account i64
  struct account {
     account( account_name o = account_name() ):owner(o){
     }
     account_name owner;
     asset        balance;
     bool is_empty()const { return !( balance.amount); }
     uint64_t primary_key()const { return owner; }
     EOSLIB_SERIALIZE( account, (owner)(balance) )
  };
  typedef eosio::multi_index< N(account), account> account_index;
  bet_index         bets;
  gbet_index        gbet;
  account_index     accounts;
};
EOSIO_ABI( dice, (offerbet)(canceloffer)(openbet)(closurebet)(reveal)(deposit)(withdraw)(reset) )
八、合约ABI
{
"____comment": "This file was generated by eosio-abigen. DO NOT EDIT - 2018-03-29T02:09:11",
  "types": [],
  "structs": [{
      "name": "bet",
      "base": "",
      "fields": [{
          "name": "id",
          "type": "uint64"
        },{
          "name": "owner",
          "type": "account_name"
        },{
          "name": "balance",
          "type": "asset"
        },{
          "name": "betid",
          "type": "uint64"
        },{
          "name": "info",
          "type": "uint64"
        }
      ]
    },{
      "name": "gbet",
      "base": "",
      "fields": [{
          "name": "id",
          "type": "uint64"
        },{
          "name": "betid",
          "type": "uint64"
        },{
          "name": "betname",
          "type": "uint64"
        },{
          "name": "open",
          "type": "uint64"
        },{
          "name": "reveal",
          "type": "uint64"
        }
      ]
    },{
      "name": "account",
      "base": "",
      "fields": [{
          "name": "owner",
          "type": "account_name"
        },{
          "name": "balance",
          "type": "asset"
        }
      ]
    },{
      "name": "offerbet",
      "base": "",
      "fields": [{
          "name": "bet",
          "type": "asset"
        },{
          "name": "player",
          "type": "account_name"
        },{
          "name": "info",
          "type": "uint64"
        }
      ]
    },{
      "name": "canceloffer",
      "base": "",
      "fields": [{
          "name": "player",
          "type": "account_name"
        }
      ]
    },{
      "name": "openbet",
      "base": "",
      "fields": [
      ]
    },{
      "name": "closurebet",
      "base": "",
      "fields": [
      ]
    },{
      "name": "reveal",
      "base": "",
      "fields": [
      ]
    },{
      "name": "deposit",
      "base": "",
      "fields": [{
          "name": "from",
          "type": "account_name"
        },{
          "name": "quantity",
          "type": "asset"
        }
      ]
    },{
      "name": "withdraw",
      "base": "",
      "fields": [{
          "name": "to",
          "type": "account_name"
        },{
          "name": "quantity",
          "type": "asset"
        }
      ]
    },{
      "name": "reset",
      "base": "",
      "fields": [
      ]
    }
  ],
  "actions": [{
      "name": "offerbet",
      "type": "offerbet",
      "ricardian_contract": ""
    },{
      "name": "canceloffer",
      "type": "canceloffer",
      "ricardian_contract": ""
    },{
      "name": "openbet",
      "type": "openbet",
      "ricardian_contract": ""
    },{
      "name": "closurebet",
      "type": "closurebet",
      "ricardian_contract": ""
    },{
      "name": "reveal",
      "type": "reveal",
      "ricardian_contract": ""
    },{
      "name": "deposit",
      "type": "deposit",
      "ricardian_contract": ""
    },{
      "name": "withdraw",
      "type": "withdraw",
      "ricardian_contract": ""
    },{
      "name": "reset",
      "type": "reset",
      "ricardian_contract": ""
    }
  ],
  "tables": [{
      "name": "bet",
      "index_type": "i64",
      "key_names": [
        "id"
      ],
      "key_types": [
        "uint64"
      ],
      "type": "bet"
    },{
      "name": "gbet",
      "index_type": "i64",
      "key_names": [
        "id"
      ],
      "key_types": [
        "uint64"
      ],
      "type": "gbet"
    },{
      "name": "account",
      "index_type": "i64",
      "key_names": [
        "owner"
      ],
      "key_types": [
        "account_name"
      ],
      "type": "account"
    }
  ],
  "ricardian_clauses": []
}
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