Bytom 信息上链教程 | 比原链Bytom

比原项目仓库：

Gitee地址：https://gitee.com/BytomBlockchain/bytom

##用比原链（Bytom）实现信息上链

很多了解比原链的都知道，比原链是专注信息和数字资产在链上交互和流转的公链项目，信息上链不是比原链核心能力，所以并没有在钱包端做一个功能入口，但是比原链提供了相关的接口可以将一些信息写到链上去。那如何实现信息上链呢？使用特殊的Retire操作，这个操作可以进行销毁资产的操作，但因为其可以附带信息，所以就可以实现信息上链的功能。

请往下看，也用postman请求演示，然后用golang写了一个接口的demo, 在用golang代码实现之前，我们先要做一些准备工作。

首先确保自己在本地已经搭建好了比原的节点，如果你还没有搭建好节点，请参考开发文档：https://docs.bytom.io/mydoc_build_environment.cn.html
确保自己账户是有足够BTM测试币，如果没有可以去比原链水龙头领取BTM测试币,领取地址：

http://test.blockmeta.com/faucet.php

发行自己的资产，参考：http://8btc.com/forum.php?mod=viewthread&tid=242940&extra=
信息上链的本质就是其实就是创建并发送一笔交易，我们都知道通过api发起交易主要有三个步骤，先 build → sign → submit，分别对应的api是 build-transaction、sign-transaction、submit-transaction。用postman请求过程如下：

请求build-transaction接口:

Bytom信息上链教程-LMLPHP

请求参数：

{
"base_transaction": null,
"actions": [{
	"account_id": "0KTCS3R5G0A02",
	"amount": 10000000,
	"asset_id": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
	"type": "spend_account"
}, {
	"account_id": "0KTCS3R5G0A02",
	"amount": 100,
	"asset_id": "608037f96e8d1613d900c67a0730cc90e2a03311fb7d091588f7eb551a6103cd",
	"type": "spend_account"
}, {
	"account_id": "0KTCS3R5G0A02",
	"amount": 100,
	"asset_id": "608037f96e8d1613d900c67a0730cc90e2a03311fb7d091588f7eb551a6103cd",
	"arbitrary": "77656c636f6d65efbc8ce6aca2e8bf8ee69da5e588b0e58e9fe5ad90e4b896e7958c",
	"type": "retire"
}],
"ttl": 0,
"time_range": 1521625823
}

请求sign-transaction接口：

Bytom信息上链教程-LMLPHP

请求参数：

{
"password": "huangxinglong123",
"transaction": {
	"allow_additional_actions": false,
	"local": true,
	"raw_transaction": "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",
	"signing_instructions": [{
		"position": 0,
		"witness_components": [{
			"keys": [{
				"derivation_path": [
					"0000002c",
					"00000099",
					"0100000000000000",
					"0100000000000000",
					"4600000000000000"
				],
				"xpub": "1c03161a08a4dbb7df153815a28f733fec1ac7579f954c4834e5ce9f0ad8deb260ecb2066a8623b69aa936f5798f4dcb9572bc476f2c8171953ce054d58a759f"
			}],
			"quorum": 1,
			"signatures": null,
			"type": "raw_tx_signature"
		}, {
			"type": "data",
			"value": "4f089176a5bca95ec9227b8a87dfec947c59453805bf46d3f5a18f8032255b5a"
		}]
	}, {
		"position": 1,
		"witness_components": [{
			"keys": [{
				"derivation_path": [
					"0000002c",
					"00000099",
					"0100000000000000",
					"0100000000000000",
					"4700000000000000"
				],
				"xpub": "1c03161a08a4dbb7df153815a28f733fec1ac7579f954c4834e5ce9f0ad8deb260ecb2066a8623b69aa936f5798f4dcb9572bc476f2c8171953ce054d58a759f"
			}],
			"quorum": 1,
			"signatures": null,
			"type": "raw_tx_signature"
		}, {
			"type": "data",
			"value": "67512f9250f559699e32c72c8af29096b1556af145f6ecc0c306e6acc88bbfaa"
		}]
	}]
}
}

请求submit-transaction接口：

Bytom信息上链教程-LMLPHP

请求参数：

 {
 "raw_transaction": "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"
  }

响应参数：

 {
"status": "success",
"data": {
    "tx_id": "5ef27b930646d468bbb436d3406972ff201aa63702518f777e31dd6a2147dddc"
  }
}

用上面返回的tx_id去比原的浏览器中去查看交易详情，就可以查看到我们上传的数据

Bytom信息上链教程-LMLPHP

参考代码：

package main

import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"net/http"
)

//build-transaction params
//https://bytom.github.io/mydoc_RPC_call.cn.html#build-transaction
type BytomAccount struct {
AccountId string `json:"account_id"`
Amount    int    `json:"amount"`
AssetId   string `json:"asset_id"`
//Arbitrary string `json:"arbitrary"`
Type string `json:"type"`
}
type BytomAccount1 struct {
AccountId string `json:"account_id"`
Amount    int    `json:"amount"`
AssetId   string `json:"asset_id"`
Arbitrary string `json:"arbitrary"`
Type      string `json:"type"`
}

type BaseTransaction struct{}

type TransactionParams struct {
BaseTransaction *BaseTransaction `json:"base_transaction"`
Actions         []interface{}    `json:"actions"`
Ttl             int              `json:"ttl"`
TimeRange       int              `json:"time_range"`
}

//sign-transaction params
//https://bytom.github.io/mydoc_RPC_call.cn.html#build-transaction
type Transaction struct {
}

type SignParams struct {
Password    string      `json:"password"`
Transaction Transaction `json:"transaction"`
}

//submit-transaction
//https://bytom.github.io/mydoc_RPC_call.cn.html#build-transaction
type SubmitParams struct {
RawTransaction string `json:"raw_transaction"`
}
type SubmitResponse struct {
TxId string `json:"tx_id"`
}

func main() {

account1, account2, account3 := BytomAccount{}, BytomAccount{}, BytomAccount1{}
account1.AccountId = "0KTCS3R5G0A02"
account1.Amount = 10000000
account1.AssetId = "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
account1.Type = "spend_account"

account2.AccountId = "0KTCS3R5G0A02"
account2.Amount = 100
account2.AssetId = "608037f96e8d1613d900c67a0730cc90e2a03311fb7d091588f7eb551a6103cd"
account2.Type = "spend_account"

account3.AccountId = "0KTCS3R5G0A02"
account3.Amount = 100
account3.AssetId = "608037f96e8d1613d900c67a0730cc90e2a03311fb7d091588f7eb551a6103cd"
account3.Arbitrary = "77656c636f6d65efbc8ce6aca2e8bf8ee69da5e588b0e58e9fe5ad90e4b896e7958c"
account3.Type = "retire"

//var array
var actions []interface{}
//append three params
array_actions := append(actions, account1, account2, account3)
transaction_params := &TransactionParams{}
transaction_params.Actions = array_actions
transaction_params.Ttl = 0
transaction_params.TimeRange = 1521625823

//本地测试网节点
//build-transaction
port := "http://127.0.0.1:9888/build-transaction"
value, err := SendTransactionRetire(transaction_params, port)
if err != nil {
	fmt.Println("err:", err)
}

fmt.Println("build-transaction接口返回的参数:", value)

//sign-transaction
//...........

//submit-transaction
//...........

}

//send post request
func SendTransactionRetire(params *TransactionParams, port   string) (v interface{}, err error) {
//以本地测试网节点连接
ParamsStr, err := json.Marshal(params)
if err != nil {
	return nil, err
}

jsonStr := bytes.NewBuffer(ParamsStr)
fmt.Println(jsonStr)

req, err := http.NewRequest("POST", port, jsonStr)
req.Header.Set("Content-Type", "application/json")
req.Header.Add("Accept", "application/json")

client := &http.Client{}
resp, err := client.Do(req)
if err != nil {
	panic(err)
}
defer resp.Body.Close()

var bodyBytes []byte
if resp.StatusCode == 200 {
	bodyBytes, err = ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
}

return string(bodyBytes), nil
}

上面的代码只是build-transaction一个步骤，另外sign-transaction和submit-transaction请求需要自己去组织参数进行请求。请求完submit-transaction 获得返回的交易hash,去区块链浏览器上查看自己的上链信息，区块链浏览器地址：http://52.82.46.157:8082/。

好了，通过以上的4个步骤，我们就可以借助比原链实现信息上链。如果你有什么疑问或者不明白，请在我们的社区联系我们，https://github.com/Bytom/bytom。