# 数字货币发行与管理 ## 简介 该智能合约实现一个简单的商业应用案例，即数字货币的发行与转账。在这之中一共分为三种角色：中央银行，商业银行，企业。其中中央银行可以发行一定数量的货币，企业之间可以进行相互的转账。主要实现如下的功能： * 初始化中央银行及其发行的货币数量 * 新增商业银行，同时央行并向其发行一定数量的货币 * 新增企业 * 商业银行向企业转给一定数量的数字货币 * 企业之间进行相互的转账 * 查询企业、银行、交易信息 ## 主要函数 * `init`：初始化中央银行，并发行一定数量的货币； * `invoke`：调用合约内部的函数； * `query`：查询相关的信息； * `createBank`：新增商业银行，同时央行向其发行一定数量的货币； * `createCompany`：新增企业； * `issueCoin`：央行再次发行一定数量的货币（归于交易）； * `issueCoinToBank`：央行向商业银行转一定数量的数字货币（归于交易）； * `issueCoinToCp`：商业银行向企业转一定数量的数字货币（归于交易行为）； * `transfer`：企业之间进行相互转账（归于交易行为）； * `getCompanys`：获取所有的公司信息，如果企业个数大于10，先访问前10个； * `getBanks`：获取所有的商业银行信息，如果商业银行个数大于10，先访问前 10 个 * `getTransactions`：获取所有的交易记录 如果交易个数大于10，先访问前 10 个； * `getCompanyById`：获取某家公司信息； * `getBankById`：获取某家银行信息； * `getTransactionBy`：获取某笔交易记录； * `writeCenterBank`：修改央行信息； * `writeBank`：修改商业银行信息； * `writeCompany`：修改企业信息； * `writeTransaction`：写入交易信息。 ## 数据结构设计 * centerBank 中央银行 * Name：名称 * TotalNumber：发行货币总数额 * RestNumber：账户余额 * ID：ID固定为 0 * bank 商业银行 * Name：名称 * TotalNumber：收到货币总数额 * RestNumber：账户余额 * ID：银行 ID * company 企业 * Name：名称 * Number：账户余额 * ID：企业 ID * transaction 交易内容 * FromType：发送方角色 //centerBank:0,Bank:1,Company:2 * FromID：发送方 ID * ToType：接收方角色 //Bank:1,Company:2 * ToID：接收方 ID * Time：交易时间 * Number：交易数额 * ID：交易 ID ## 接口设计 ### `init` request 参数: ``` args[0] 银行名称 args[1] 初始化发布金额 ``` response 参数: ```json {"Name":"XXX","TotalNumber":"0","RestNumber":"0","ID":"XX"} ``` ### `createBank` request 参数: ``` args[0] 银行名称 ``` response 参数: ```json {"Name":"XXX","TotalNumber":"0","RestNumber":"0","ID":"XX"} ``` ### `createCompany` request 参数: ``` args[0] 公司名称 ``` response 参数: ```json {"Name":"XXX","Number":"0","ID":"XX"} ``` ### `issueCoin` request 参数: ``` args[0] 再次发行货币数额 ``` response 参数: ```json {"FromType":"0","FromID":"0","ToType":"0","ToID":"0","Time":"XX","Number":"XX","ID":"XX"} ``` ### `issueCoinToBank` request 参数: ``` args[0] 商业银行ID args[1] 转账数额 ``` response 参数: ```json {"FromType":"0","FromID":"0","ToType":"1","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"} ``` ### `issueCoinToCp` request 参数: ``` args[0] 商业银行ID args[1] 企业ID args[2] 转账数额 ``` response 参数: ```json {"FromType":"1","FromID":"XX","ToType":"2","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"} ``` ### `transfer` request 参数: ``` args[0] 转账用户ID args[1] 被转账用户ID args[2] 转账余额 ``` response 参数: ```json {"FromType":"2","FromID":"XX","ToType":"2","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"} ``` ### `getBanks` response 参数 ```json [{"Name":"XXX","Number":"XX","ID":"XX"},{"Name":"XXX","Number":"XX","ID":"XX"},...] ``` ### `getCompanys` response 参数 ```json [{"Name":"XXX","TotalNumber":"XX","RestNumber":"XX","ID":"XX"},{"Name":"XXX","TotalNumber":"XX","RestNumber":"XX","ID":"XX"},...] ``` ### `getTransactions` response 参数 ```json [{"FromType":"XX","FromID":"XX","ToType":"XX","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"},{"FromType":"XX","FromID":"XX","ToType":"XX","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"},...] ``` ### `getCenterBank` response 参数 ```json [{"Name":"XX","TotalNumber":"XX","RestNumber":"XX","ID":"XX"}] ``` ### `getBankById` request 参数 ``` args[0] 商业银行ID ``` response 参数 ```json [{"Name":"XX","TotalNumber":"XX","RestNumber":"XX","ID":"XX"}] ``` ### `getCompanyById` request 参数 ``` args[0] 企业ID ``` response 参数 ```json [{"Name":"XXX","Number":"XX","ID":"XX"}] ``` ### `getTransactionById` request 参数 ``` args[0] 交易ID ``` response 参数 ```json {"FromType":"XX","FromID":"XX","ToType":"XX","ToID":"XX","Time":"XX","Number":"XX","ID":"XX"} ``` ### `writeCenterBank` request 参数 ``` CenterBank ``` response 参数 ``` err nil 为成功 ``` ### `writeBank` request 参数 ``` Bank ``` response 参数 ``` err nil 为成功 ``` ### `writeCompany` request 参数 ``` Company ``` response 参数 ``` err nil 为成功 ``` ### `writeTransaction` request 参数 ``` Transaction ``` response 参数 ``` err nil 为成功 ``` ### 其它 查询时为了兼顾读速率，将一些信息备份存放在非区块链数据库上也是一个较好的选择。