fisco bcosV3 Table智能合约开发

环境 ： fisco bcos 3.11.0
webase-front : 3.1.1
console 3.8.0
table合约【3.2.0版本后的】

前言

最近在做毕设，数据的存储方式考虑使用fisco-bcos的table表存储，经过这几天的研究，发现对于fisco2和 fisco3版本的table表合约功能差异还是比较大的，比较起来V3的table合约功能性更丰富，更加的方便开发。

读者们要是没用过v3的链子，可以在fisco3 这里简单启动一条链子，Air版本的搭建和fisco2搭建的链子命令无多大差别【文章后面也有对应的控制台搭建命令，注意控制台2和3版本的链子不互通】
然后就是webase-front要使用3.0以上的版本，链接在这里https://webasedoc.readthedocs.io/zh-cn/lab/docs/WeBASE-Install/developer.html

关于fisco3 的Table合约

不知道是不是webase-front 版本的问题，我并未在其代码仓库里找到Table.sol合约的文件，只有KVTable.sol合约。然后我去github的fisco仓库找到了fisco3的版本合约文件，还附带两个合约，都需要import进去才行
[更新一下，这些合约也可以在控制台3.8.0上的contracts/solidity文件夹上找到，注意：v3版本有两个Table合约，一个是3.2.0版本以上，一个是3.2.0以前的版本，我所有介绍的是3.2.0以上的，官方文档给的是3.2.0以前的例子]

Table.sol

// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.6.10 <0.8.20;
pragma experimental ABIEncoderV2;
import "./EntryWrapper.sol";// KeyOrder指定Key的排序规则，字典序和数字序，如果指定为数字序，key只能为数字
enum KeyOrder {Lexicographic, Numerical}
struct TableInfo {KeyOrder keyOrder;string keyColumn;string[] valueColumns;
}// 更新字段，用于update
struct UpdateField {string columnName;// 考虑工具类string value;
}// 筛选条件，大于、大于等于、小于、小于等于
enum ConditionOP {GT, GE, LT, LE, EQ, NE, STARTS_WITH, ENDS_WITH, CONTAINS}
struct Condition {ConditionOP op;string field;string value;
}// 数量限制
struct Limit {uint32 offset;// count limit max is 500uint32 count;
}// 表管理合约，是静态Precompiled，有固定的合约地址
abstract contract TableManager {// 创建表，传入TableInfofunction createTable(string memory path, TableInfo memory tableInfo) public virtual returns (int32);// 创建KV表，传入key和value字段名function createKVTable(string memory tableName, string memory keyField, string memory valueField) public virtual returns (int32);// 只提供给Solidity合约调用时使用function openTable(string memory path) public view virtual returns (address);// 变更表字段// 只能新增字段，不能删除字段，新增的字段默认值为空，不能与原有字段重复function appendColumns(string memory path, string[] memory newColumns) public virtual returns (int32);// 获取表信息function descWithKeyOrder(string memory tableName) public view virtual returns (TableInfo memory);
}// 表合约，是动态Precompiled，TableManager创建时指定地址
abstract contract Table {// 按key查询entryfunction select(string memory key) public virtual view returns (Entry memory);// 按条件批量查询entry，condition为空则查询所有记录function select(Condition[] memory conditions, Limit memory limit) public virtual view returns (Entry[] memory);// 按照条件查询count数据function count(Condition[] memory conditions) public virtual view returns (uint32);// 插入数据function insert(Entry memory entry) public virtual returns (int32);// 按key更新entryfunction update(string memory key, UpdateField[] memory updateFields) public virtual returns (int32);// 按条件批量更新entry，condition为空则更新所有记录function update(Condition[] memory conditions, Limit memory limit, UpdateField[] memory updateFields) public virtual returns (int32);// 按key删除entryfunction remove(string memory key) public virtual returns (int32);// 按条件批量删除entry，condition为空则删除所有记录function remove(Condition[] memory conditions, Limit memory limit) public virtual returns (int32);
}abstract contract KVTable {function get(string memory key) public view virtual returns (bool, string memory);function set(string memory key, string memory value) public virtual returns (int32);
}

EntryWrapper.sol

这个类似于mybatisplus里面的wrapper条件构造器，用来进行附加查询条件使用，还有Entry用来做返回数据的数据结构

// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.6.10 <0.8.20;
pragma experimental ABIEncoderV2;
import "./Cast.sol";// 记录，用于select和insert
struct Entry {string key;string[] fields; // 考虑2.0的Entry接口，临时Precompiled的问题，考虑加工具类接口
}contract EntryWrapper {   Cast constant cast =  Cast(address(0x100f));  Entry entry;constructor(Entry memory _entry) public {entry = _entry;}function setEntry(Entry memory _entry) public {entry = _entry;}function getEntry() public view returns(Entry memory) {return entry;}function fieldSize() public view returns (uint256) {return entry.fields.length;}function getInt(uint256 idx) public view returns (int256) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return cast.stringToS256(entry.fields[idx]);}function getUInt(uint256 idx) public view returns (uint256) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return cast.stringToU256(entry.fields[idx]);}function getAddress(uint256 idx) public view returns (address) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return cast.stringToAddr(entry.fields[idx]);}function getBytes64(uint256 idx) public view returns (bytes1[64] memory) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return bytesToBytes64(bytes(entry.fields[idx]));}function getBytes32(uint256 idx) public view returns (bytes32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return cast.stringToBytes32(entry.fields[idx]);}function getString(uint256 idx) public view returns (string memory) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");return entry.fields[idx];}function set(uint256 idx, int256 value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = cast.s256ToString(value);return 0;}function set(uint256 idx, uint256 value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = cast.u256ToString(value);return 0;}function set(uint256 idx, string memory value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = value;return 0;}function set(uint256 idx, address value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = cast.addrToString(value);return 0;}function set(uint256 idx, bytes32 value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = cast.bytes32ToString(value);return 0;}function set(uint256 idx, bytes1[64] memory value) public returns(int32) {require(idx >= 0 && idx < fieldSize(), "Index out of range!");entry.fields[idx] = string(bytes64ToBytes(value));return 0;}function setKey(string memory value) public {entry.key = value;}function getKey() public view returns (string memory) {return entry.key;}function bytes64ToBytes(bytes1[64] memory src) private pure returns(bytes memory) {bytes memory dst = new bytes(64);for(uint32 i = 0; i < 64; i++) {dst[i] = src[i][0];}return dst;}function bytesToBytes64(bytes memory src) private pure returns(bytes1[64] memory) {bytes1[64] memory dst;for(uint32 i = 0; i < 64; i++) {dst[i] = src[i];}return dst;}
}

Cast.sol

// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.6.10 <0.8.20;
pragma experimental ABIEncoderV2;abstract contract Cast {function stringToS256(string memory) public virtual view returns (int256);function stringToS64(string memory) public virtual view returns (int64);function stringToU256(string memory) public virtual view returns (uint256);function stringToAddr(string memory) public virtual view returns (address);function stringToBytes32(string memory) public virtual view returns (bytes32);function s256ToString(int256) public virtual view returns (string memory);function s64ToString(int64) public virtual view returns (string memory);function u256ToString(uint256) public virtual view returns (string memory);function addrToString(address) public virtual view returns (string memory);function bytes32ToString(bytes32) public virtual view returns (string memory);
}

编写TableTest

这里我直接用官网的例子代码进行测试，不过官网例子与实际的table合约有出入，需要进行修改

https://fisco-bcos-doc.readthedocs.io/zh-cn/latest/docs/contract_develop/c++_contract/use_crud_precompiled.html

// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.6.10 <0.8.20;
pragma experimental ABIEncoderV2;
import "./Table.sol";contract TestTable{// 创建TableManager对象，其在区块链上的固定地址是0x1002
TableManager constant tm =  TableManager(address(0x1002));
Table table;
string constant TABLE_NAME = "t_test";
constructor () public{// 创建t_test表，表的主键名为id，其他字段名为name和agestring[] memory columnNames = new string[](2);columnNames[0] = "name";columnNames[1] = "age";KeyOrder keyOrder;TableInfo memory tf = TableInfo(KeyOrder.Numerical,"id", columnNames);tm.createTable(TABLE_NAME, tf);// 获取真实的地址，存在合约中address t_address = tm.openTable(TABLE_NAME);require(t_address!=address(0x0),"");table = Table(t_address);
} function insert(string memory id,string memory name,string memory age) public returns (int32){string[] memory columns = new string[](2);columns[0] = name;columns[1] = age;Entry memory entry = Entry(id, columns);int32 result = table.insert(entry);// emit InsertResult(result);return result;
}function update(string memory id, string memory name, string memory age) public returns (int32){UpdateField[] memory updateFields = new UpdateField[](2);updateFields[0] = UpdateField("name", name);updateFields[1] = UpdateField("age", age);int32 result = table.update(id, updateFields);return result;
}function remove(string memory id) public returns(int32){int32 result = table.remove(id);return result;
}function select(string memory id) public view returns (string memory,string memory)
{Entry memory entry = table.select(id);string memory name;string memory age;if(entry.fields.length==2){name = entry.fields[0];age = entry.fields[1];}return (name,age);
}// enum ConditionOP {GT, GE, LT, LE, EQ, NE, STARTS_WITH, ENDS_WITH, CONTAINS}
// struct Condition {
//     ConditionOP op;
//     string field;
//     string value;
// }
function selectMore(string memory age)publicviewreturns (Entry[] memory entries)
{Condition[] memory conds = new Condition[](1);Condition memory eq= Condition({op: ConditionOP.EQ, field: "age",value: age});conds[0] = eq;Limit memory limit = Limit({offset: 0, count: 100});entries = table.select(conds, limit);return entries;
}}

TableInfo的问题

实际的TableInfo 结构如下

// KeyOrder指定Key的排序规则，字典序和数字序，如果指定为数字序，key只能为数字
enum KeyOrder {Lexicographic, Numerical}
struct TableInfo {KeyOrder keyOrder;string keyColumn;string[] valueColumns;
}

是需要三个参数的，而官网的例子只用两个参数，缺少的第一个参数是枚举类，意思是你的主键是string类型还是数字类型，需要标明。

Condition的问题

实际的Condition结构如下

// 筛选条件，大于、大于等于、小于、小于等于
enum ConditionOP {GT, GE, LT, LE, EQ, NE, STARTS_WITH, ENDS_WITH, CONTAINS}
struct Condition {ConditionOP op;string field;string value;
}

官网的只有两个参数，缺少的那个参数是field，也就是此条件是要用在表的哪个字段时安个。

关于主键的问题

在fisco2的table表合约开发时候，因其的设计，导致主键是可以重复的。
但在测试fisco3的table表合约开发的时候，我用重复的主键添加多个数据，发现它遵守了主键唯一的规则，有兴趣的读者可以去测试一下，特别是用TestTable的selectMore，把field改成主键字段，可以测试到返回不了多个数据

结语

这段时间会继续开发v3的table合约，在开发的时候遇到的坑和新发现会持续更新到博客上