# Blockchain / 使用 BDK 來創建你的第一個區塊鏈吧！

嗨各位，不知道大家有沒有關注到這則新聞，比特幣最近創了歷史新高，原本走勢薄弱的以太幣也在短短一週內強勢拉盤了將近三十個點（撰文日期 2025.07.17），區塊鏈還真是個有趣的東西對吧！？ 不過今天不和大家聊金融市場或加密貨幣，是想向大家介紹一個我最近發現的很有趣的工具: 「Blockchain Development Kits（BDK）」，它是由國泰金控區塊鏈團隊在 GitHub 上開源的區塊鏈部署工具，目的是協助同業與異業夥伴透過便捷的指令快速部署，進一步加快聯盟鏈推展速度！

以下我們將使用 Golang 以及 Docker-Compose，在 Ubuntu 中搭建起一個 Hyperledger Fabric，並撰寫一份智能合約使整個網路支援讀取與寫入資料。

## Chapter 1: Network Architecture Overview

  graph TD
      subgraph "Orderer Organization"
          O1[orderer0:7050]
          O2[orderer1:7150]
          O1 <--> O2
      end

      subgraph "Org0"
          P01[peer0:7051_Anchor]
          P02[peer1]
      end

      subgraph "Org1"
          P11[peer0]
          P12[peer1:7151_Anchor]
      end

      subgraph "Channel: test"
          CC[fabcar chaincode v1]
      end

      %% Orderers serve the channel
      O1 -.-> CC
      O2 -.-> CC

      %% Peers join channel and run chaincode
      P01 --> CC
      P02 --> CC
      P11 --> CC
      P12 --> CC

      %% Peer gossip within orgs
      P01 <--> P02
      P11 <--> P12

      classDef orderer fill:#e1f5fe,stroke:#0277bd,stroke-width:2px
      classDef peer fill:#f3e5f5,stroke:#7b1fa2,stroke-width:2px
      classDef chaincode fill:#e8f5e8,stroke:#388e3c,stroke-width:2px
      classDef external fill:#fff3e0,stroke:#f57900,stroke-width:2px

      class O1,O2 orderer
      class P01,P02,P11,P12 peer
      class CC chaincode
      class P01,P12 external

## Chapter 2: Fabric Network

:::danger
在開始前，請確認您的系統中已經安裝 Golang, node.js, docker 以及 docker-compose !
:::

### 2.1 compose up orderer & peer

#### 2.1.1 touch `create.json`@`~/.bdk`

我這邊的配置和官方文件不太一樣，因為在實作的過程中發現 `org0.peer0` 和 `org1.peer0` 兩個節點的端口會有衝突。另外，在之後我們是打算將 `org0.peer0` 和 `org1.peer1` 作為 Anchor Peer，所以做出了以下改動。

{
    "ordererOrgs": [
        {
            "name": "Org0Orderer",
            "domain": "orderer.org0.example.com",
            "enableNodeOUs": true,
            "hostname": [
                "orderer0",
                "orderer1"
            ],
            "ports": [
                {
                    "port": 7050,
                    "isPublishPort": true,
                    "operationPort": 8443,
                    "isPublishOperationPort": true
                },
                {
                    "port": 7150,
                    "isPublishPort": true,
                    "operationPort": 8543,
                    "isPublishOperationPort": true
                }
            ]
        }
    ],
    "peerOrgs": [
        {
            "name": "Org0",
            "domain": "org0.example.com",
            "enableNodeOUs": true,
            "peerCount": 2,
            "userCount": 1,
            "ports": [
                {
                    "port": 7051,
                    "isPublishPort": true,
                    "operationPort": 9443,
                    "isPublishOperationPort": true
                },
                {
                    "port": 7051,
                    "isPublishPort": false,
                    "operationPort": 9443,
                    "isPublishOperationPort": false
                }
            ]
        },
        {
            "name": "Org1",
            "domain": "org1.example.com",
            "enableNodeOUs": true,
            "peerCount": 2,
            "userCount": 1,
            "ports": [
                {
                    "port": 7051,
                    "isPublishPort": false,
                    "operationPort": 9443,
                    "isPublishOperationPort": false
                },
                {
                    "port": 7151,
                    "isPublishPort": true,
                    "operationPort": 9543,
                    "isPublishOperationPort": true
                }
            ]
        }
    ]
}

#### 2.1.2 create network command

`bdk` 指令語法設計的邏輯是：

BDK，請在 [什麼平台] 上，對 [什麼東西] 執行 [什麼動作]

$ bdk fabric network create -f create.json --create-full
# @~/.bdk/fabri

#### 2.1.3 build nodes with interactive mode

$ bdk fabric orderer up -i
$ bdk fabric peer up -i

### 2.2 build & join a channel

# Org0 的 peer0 建立新的 channel
export BDK_ORG_NAME='Org0'
export BDK_ORG_DOMAIN='org0.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric channel create -i

# Org0 的 peer0 加入 channel
bdk fabric channel join -i

# Org0 的 peer1 加入 channel
export BDK_HOSTNAME='peer1'

bdk fabric channel join -i

# Org1 的 peer0 加入 channel
export BDK_ORG_NAME='Org1'
export BDK_ORG_DOMAIN='org1.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric channel join -i

# Org1 的 peer1 加入 channel
export BDK_HOSTNAME='peer1'

bdk fabric channel join -i

互動模式的選項部分，則是統一選擇：

✔ What is your channel name? › test
✔ Ordering service endpoint › orderer0.orderer.org0.example.com:7050

### 2.3 set up anchor peers

# 更新 Org0 的 anchor peer
export BDK_ORG_NAME='Org0'
export BDK_ORG_DOMAIN='org0.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric channel update-anchorpeer -i

# Org1 的 peer1 加入 channel
export BDK_ORG_NAME='Org1'
export BDK_ORG_DOMAIN='org1.example.com'
export BDK_HOSTNAME='peer1'

bdk fabric channel update-anchorpeer -i

## Chapter 3: Smart Contract

詳細程式碼請參見 GitHub Repo: https://github.com/marvelcn015/bdk-fabcar

### 3.1 File Structure

chaincode/fabric/go/
├── go.mod              # Go module dependencies
├── main.go             # Chaincode entry point
├── fabcar.go           # Main chaincode structure and interface
├── business_logic.go   # Core business operations (CRUD)
├── queries.go          # Advanced query operations
├── utils.go            # Validation and utility functions
├── fabcar_test.go      # Comprehensive test suite
└── README.md           # This documentation

### 3.2 API Methods

#### 3.2.1 Initialize Chaincode

Function: Init
Description: Initializes the chaincode with sample car data

#### 3.2.2 Query Single Car

Function: queryCar
Arguments: [carKey]
Example: queryCar "CAR0"

#### 3.2.3 Query All Cars

Function: queryAllCars
Arguments: []
Example: queryAllCars

#### 3.2.4 Create New Car

Function: createCar
Arguments: [carKey, make, model, color, owner, year, price]
Example: createCar "CAR100" "BMW" "X5" "black" "John Doe" "2022" "75000"

#### 3.2.5 Update Car

Function: updateCar
Arguments: [carKey, make, model, color, owner, year, price]
Example: updateCar "CAR0" "Toyota" "Prius" "green" "Tomoko" "2018" "26000"

#### 3.2.6 Change Car Owner

Function: changeCarOwner
Arguments: [carKey, newOwner]
Example: changeCarOwner "CAR0" "Alice Smith"

#### 3.2.7 Delete Car

Function: deleteCar
Arguments: [carKey]
Example: deleteCar "CAR0"

#### 3.2.8 Query Cars by Owner

Function: queryCarsByOwner
Arguments: [ownerName]
Example: queryCarsByOwner "John Doe"

#### 3.2.9 Query Cars by Range

Function: queryCarsByRange
Arguments: [startKey, endKey]
Example: queryCarsByRange "CAR0" "CAR9"

#### 3.2.10 Get Car History

Function: getCarHistory
Arguments: [carKey]
Example: getCarHistory "CAR0"

#### 3.2.11 Get Car Count

Function: getCarCount
Arguments: []
Example: getCarCount

## Chapter 4: Chaincode Deployment

### 4.1 部署的五個階段 & 指令

flowchart TB
    A[Package<br/>打包] --> B[Install<br/>安裝]
    B --> C[Approve<br/>批准]
    C --> D[Commit<br/>部署]
    D --> E[Invoke<br/>執行]
    
    A --> A1[編譯程式碼]
    B --> B1[複製到各節點]
    C --> C1[組織決策階段]
    D --> D1[全網路部署]
    E --> E1[實際交易執行]
    
    style A fill:#e1f5fe
    style B fill:#e8f5e8
    style C fill:#fff3e0
    style D fill:#fce4ec
    style E fill:#f3e5f5

### 4.2 各階段參與者

| 階段 | 執行者 | 作用範圍 | 是否需要共識 |
|------|--------|----------|-------------|
| Package | 任一開發者 | 本地 | ❌ |
| Install | 各 Peer 節點 | 節點層級 | ❌ |
| Approve | 各組織 | 組織層級 | ❌ |
| Commit | 任一組織 | 全網路 | ✅ |
| Invoke | 任一授權用戶 | 全網路 | ✅ |

### 4.3 Install & Approve

# Org0 的 peer0 安裝、同意 Chaincode
export BDK_ORG_NAME='Org0'
export BDK_ORG_DOMAIN='org0.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric chaincode install -i
bdk fabric chaincode approve -i

# Org1 的 Anchor Peer 也這麼做
export BDK_ORG_NAME='Org1'
export BDK_ORG_DOMAIN='org1.example.com'
export BDK_HOSTNAME='peer1'

bdk fabric chaincode install -i
bdk fabric chaincode approve -i

# Org0 的 peer1 安裝 Chaincode
export BDK_ORG_NAME='Org0'
export BDK_ORG_DOMAIN='org0.example.com'
export BDK_HOSTNAME='peer1'

bdk fabric chaincode install -i

# Org1 的 peer0 也這麼做
export BDK_ORG_NAME='Org1'
export BDK_ORG_DOMAIN='org1.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric chaincode install -i

### 4.4 Commit & Init Invoke

export BDK_ORG_NAME='Org0'
export BDK_ORG_DOMAIN='org0.example.com'
export BDK_HOSTNAME='peer0'

bdk fabric chaincode commit -i
bdk fabric chaincode invoke -i

---

接下來，就可以搭配各種自訂好的 Arguments 執行合約中的函數囉~

> BDK Offical Document:
https://github.com/cathayddt/bdk/tree/master
>
> GitHub Repo:
https://github.com/marvelcn015/bdk-fabcar
>
> 2025 / 07 / 17, by Aaron Yeh