The Graph监听合约事件：从部署到查询

0xwu
发布于 11小时前
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使用The Graph官方的Subgraph Studio在线平台来监控合约事件

# 1. 前言
The Graph 是一个去中心化的区块链数据索引协议，让你可以像查询数据库一样，用 GraphQL 查询区块链数据。

1. 为什么需要？

区块链上的数据虽然公开，但查询效率低、结构复杂，想查某个合约的交互历史，要从成千上万个区块中找，太麻烦了。  而The Graph的作用就是提前监听区块链事件，把你关心的数据抓出来、处理好、存到数据库，然后开放查询接口。

2. 使用场景
+ Uniswap 查询用户交易记录
+ Lens Protocol 查用户发布的帖子
+ ENS 查某地址注册的域名
+ NFT 市场查某个藏品的历史买卖记录

![image.png](https://img.learnblockchain.cn/attachments/2025/05/zlAyacNz6824a6b4376bd.png)

3. 大概流程：
+ 开发者设计Subgraph子图，即定义需要监听的合约和监听规则，比如监听哪些事件？怎么处理数据？存什么字段？怎么查询？ 然后定义好的规则上传到IPFS；
+  GraphNode 是一个区块链索引节点，它负责扫描区块，并读取IPFS中规则来解析区块数据，然后存储到 PostgreSQL数据库中；
+ 用户通过GraphNode提供的GraphQL接口，来查询感兴趣的数据；

4. 便于理解：
+ 区块链数据 = 河水中的鱼
+ SubGraph = 你设计捞网的形状，决定打捞大鱼还是小鱼；
+ GraphNode = 打捞的工人，用捞网去小河中捞鱼，捞到的鱼放到箱子里；
+ GraphQL查询 = 从箱子中找到你想要的鱼；

# 2. 在线部署
Subgraph Studio 是 The Graph 官方提供的图形化工具，用来创建、测试、部署和管理 Subgraph 的 Web 平台。

官方教程：[https://thegraph.com/docs/zh/subgraphs/quick-start/](https://thegraph.com/docs/zh/subgraphs/quick-start/)

我们在此平台上来监听Counter合约的事件，监听事件包括：SetNumber和Increment，来监听number的变化；

准备条件

1. 加密钱包：为了登录Web平台
2. 已部署的合约地址：用于监控合约的事件，注意**该合约存在事件**；我已在Ethereum Sepolia网络上成功部署和验证的[Counter合约](https://sepolia.etherscan.io/address/0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856#code)；
3. 安装Node.js：推荐安装v23.11.0。用于安装Graph 客户端或相关依赖包；安装工具支持npm，yarn和 pnpm

## 2.1 创建subgraph
1. 使用metamask钱包登录网站：[https://thegraph.com/studio/](https://thegraph.com/studio/)
2. 创建一个子图：[Counter](https://thegraph.com/studio/subgraph/counter/)子图。创建成功后，在右栏提供了具体的创建步骤；

![image.png](https://img.learnblockchain.cn/attachments/2025/05/7oHhbaYQ6824a8fc1d982.png)

## 2.2 安装graph客户端
在本地电脑上安装graph客户端

```powershell
# npm安装graph客户端
$ npm install -g @graphprotocol/graph-cli@latest
npm warn deprecated inflight@1.0.6: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful.
npm warn deprecated rimraf@2.7.1: Rimraf versions prior to v4 are no longer supported
npm warn deprecated glob@7.2.3: Glob versions prior to v9 are no longer supported
added 422 packages in 22s
86 packages are looking for funding
  run `npm fund` for details

# 查看客户端版本
$ graph --version
@graphprotocol/graph-cli/0.97.0 win32-x64 node-v23.11.0
```

## 2.3 初始化subgraph
根据执行输入参数

1. 选择sepolia网络，回车，回车，回车
2. 输入合约地址：该合约需要验证通过，才能解析成功其中的ABI信息，否则要自行执行ABI的绝对路径。这是我验证通过的[Counter合约地址](https://sepolia.etherscan.io/address/0xb78473a261797b9fa4a18adff4ad89b2b94b8856#code)
3. 一路回车，使用默认参数；

```shell
$ graph init counter

√ Network · Ethereum Sepolia Testnet · sepolia · https://sepolia.etherscan.io  # 完整输入Ethereum Sepolia Testnet，选择sepolia网络
√ Source · Smart Contract · ethereum				# 回车
√ Subgraph slug · counter					# 回车
√ Directory to create the subgraph in · counter			# 回车
√ Contract address · 0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856	# 输入验证通过的合约地址
√ Fetching ABI from Sourcify API...
√ Fetching ABI from Contract API...
√ Fetching start block from Contract API...
√ Fetching contract name from Contract API...
√ Start block · 8310332						# 回车，确认部署合约的区块号
? Contract name » counter					# 回车
√ Contract name · counter
√ Index contract events as entities (Y/n) · true		# 回车
  Generate subgraph
  Write subgraph to directory
√ Create subgraph scaffold
√ Initialize networks config
√ Initialize subgraph repository
√ Install dependencies with npm install
√ Generate ABI and schema types with npm run codegen
√ Add another contract? (y/N) · false				# 回车

Subgraph counter created in counter
Next steps:
  1. Run `graph auth` to authenticate with your deploy key.
  2. Type `cd counter` to enter the subgraph.
  3. Run `npm run deploy` to deploy the subgraph.
Make sure to visit the documentation on https://thegraph.com/docs/ for further information.
```

## 2.4 授权
授权码在web端中查找 deploy key

```shell
$ graph auth 635702bb8e772ac010c612105bd4b2f4
Deploy key set for https://api.studio.thegraph.com/deploy/
```

![image.png](https://img.learnblockchain.cn/attachments/2025/05/8BYqrBxN6824a75671ff6.png)

## 2.5 生成和编译
三个核心文件：

1. schema.graphql：定义解析数据的结构，即作为存储到PostgreSQL的实体结构，也是前端查询接口的传参；
2. subgraph.yaml：定义数据来源和处理规则；告诉GraphNode监听哪些合约，从哪个区块开始，匹配哪些事件，调用哪个处理函数等；
3. mapping.ts：定义事件的处理逻辑，将解析数据转换为实体存入PostgreSQL;

```shell
# 进入初始化项目目录
$ cd counter/

# 生成和编译
$ graph codegen && graph build
  Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4
√ Apply migrations
√ Load subgraph from subgraph.yaml						# 数据来源和处理规则
  Load contract ABI from abis\counter.json
√ Load contract ABIs
  Generate types for contract ABI: counter (abis\counter.json)
  Write types to generated\counter\counter.ts
√ Generate types for contract ABIs
√ Generate types for data source templates
√ Load data source template ABIs
√ Generate types for data source template ABIs
√ Load GraphQL schema from schema.graphql					# 解析数据的实体
  Write types to generated\schema.ts
√ Generate types for GraphQL schema

Types generated successfully							# 生成成功

Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4
√ Apply migrations
√ Load subgraph from subgraph.yaml
  Compile data source: counter => build\counter\counter.wasm
√ Compile subgraph
  Copy schema file build\schema.graphql
  Write subgraph file build\counter\counter.json
  Write subgraph manifest build\subgraph.yaml
√ Write compiled subgraph to build\

Build completed: build\subgraph.yaml						# 编译完成
```

### 2.5.1 schema.graphql文件
生成的schema.graphql文件内容

定义解析数据的结构，即作为存储到PostgreSQL的实体结构，也是前端查询接口的传参；

```typescript
type Increment @entity(immutable: true) {  	# @entity 表示这是需要被GraphNode存储到PostgreSQL的数据
  id: Bytes!					# 所有 Entity 都需要有一个 id 字段
  sender: Bytes! # address
  newValue: BigInt! # uint256
  blockNumber: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}

type SetNumber @entity(immutable: true) {
  id: Bytes!
  sender: Bytes! # address
  newNumber: BigInt! # uint256
  blockNumber: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}
```

### 2.5.2 subgraph.yaml文件
定义数据来源和处理规则；告诉GraphNode监听哪些合约，从哪个区块开始，匹配哪些事件，调用哪个处理函数等；

```yaml
specVersion: 1.3.0
indexerHints:
  prune: auto
schema:
  file: ./schema.graphql
dataSources:					# 要监听的链上合约及其事件
  - kind: ethereum
    name: counter
    network: sepolia
    source:
      address: "0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856"
      abi: counter				# 对应事件的 ABI 文件，用于解析日志
      startBlock: 8310332			# 指定从哪个区块开始监听（提升效率）
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Increment
        - SetNumber
      abis:
        - name: counter
          file: ./abis/counter.json
        eventHandlers:				# 指定事件和处理函数的映射关系
        - event: Increment(indexed address,uint256)
          handler: handleIncrement
        - event: SetNumber(indexed address,uint256)
          handler: handleSetNumber
      file: ./src/counter.ts	# 指定映射逻辑所在的 TypeScript 文件
```

### 2.5.3 mapping.ts
该案例的mapping.ts 对应为 counter/src/counter.ts；

定义事件的处理逻辑，将解析数据转换为实体存入PostgreSQL;

```typescript
import {
  Increment as IncrementEvent,
  SetNumber as SetNumberEvent
} from "../generated/counter/counter"
import { Increment, SetNumber } from "../generated/schema"

export function handleIncrement(event: IncrementEvent): void {
  let entity = new Increment(			// 监听到 IncrementEvent 后，创建一个entity实体。
    event.transaction.hash.concatI32(event.logIndex.toI32())
  )
  entity.sender = event.params.sender		// 利用事件参数填充字段
  entity.newValue = event.params.newValue

entity.blockNumber = event.block.number
  entity.blockTimestamp = event.block.timestamp
  entity.transactionHash = event.transaction.hash

entity.save()					// 然后 .save() 保存进数据库。
}

export function handleSetNumber(event: SetNumberEvent): void {
  let entity = new SetNumber(
    event.transaction.hash.concatI32(event.logIndex.toI32())
  )
  entity.sender = event.params.sender
  entity.newNumber = event.params.newNumber

entity.blockNumber = event.block.number
  entity.blockTimestamp = event.block.timestamp
  entity.transactionHash = event.transaction.hash

entity.save()
}

```

## 2.6 部署
将三个核心文件上传IPFS，并部署Graph node

```shell
$ graph deploy counter

# 正确结果
Which version label to use? (e.g. "v0.0.1") · v0.0.1		# 输入版本标签，用于标识本次部署的子图版本
  Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4

# 编译输出的关键文件（已准备部署）
  Write subgraph file build\counter\counter.json	# subgraph.yaml 编译后的 JSON 格式配置
  Write subgraph manifest build\subgraph.yaml		# 拷贝原始 manifest 文件用于 build 目录中的部署引用
√ Write compiled subgraph to build\			# 编译完成，所有核心文件写入 build 目录

# 将核心文件上传到 IPFS（去中心化内容地址存储）
  Add file to IPFS build\schema.graphql			# GraphQL 实体结构定义（决定可查询字段）
                .. QmezFjzFxkKzgjYZzNgM67kEbwFWFqYSCjrGmXwLSsfas5# IPFS文件的唯一哈希值，保证唯一防篡改
  Add file to IPFS build\counter\counter.json		# 索引说明书（合约地址、处理事件、mapping 指向等）
                .. QmUp4K2wbtfL6BS6RkcPmqMrEgzDJFbiG8spBtVFY7cPCX
  Add file to IPFS build\counter\counter.wasm		# 编译后的 mapping.ts 文件（事件处理逻辑）
                .. QmU7rqqieWR3v8rcxwtEvDkWM12ymA4E5bK5eHtpf2zCUa
√ Upload subgraph to IPFS															# 上传成功！

Build completed: QmQ3iiVTZByx28jUuN1nXPAHr2JcwxgjfAVjDa9gYvZhyc	# 整个子图的 IPFS 根哈希（代表本次部署的唯一标识）

- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl 	  # 部署到graph node节点
Deployed to https://thegraph.com/studio/subgraph/counter	  # 部署到studio中 
```

## 2.7 验证
部署完成后，在回到web端就会发生变化

当我调用Counter合约的两个函数时，etherscan 和 subgraph studio上都能看到发生的事件；

合约事件：[https://sepolia.etherscan.io/address/0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856#events](https://sepolia.etherscan.io/address/0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856#events)

Subgraph查询：[https://thegraph.com/studio/subgraph/counter/playground](https://thegraph.com/studio/subgraph/counter/playground)

![image.png](https://img.learnblockchain.cn/attachments/2025/05/CrIsTdRF6824a8626b0be.png)

1. 前言

The Graph 是一个去中心化的区块链数据索引协议，让你可以像查询数据库一样，用 GraphQL 查询区块链数据。

为什么需要？

区块链上的数据虽然公开，但查询效率低、结构复杂，想查某个合约的交互历史，要从成千上万个区块中找，太麻烦了。而The Graph的作用就是提前监听区块链事件，把你关心的数据抓出来、处理好、存到数据库，然后开放查询接口。

使用场景
- Uniswap 查询用户交易记录
- Lens Protocol 查用户发布的帖子
- ENS 查某地址注册的域名
- NFT 市场查某个藏品的历史买卖记录

大概流程：
- 开发者设计Subgraph子图，即定义需要监听的合约和监听规则，比如监听哪些事件？怎么处理数据？存什么字段？怎么查询？然后定义好的规则上传到IPFS；
- GraphNode 是一个区块链索引节点，它负责扫描区块，并读取IPFS中规则来解析区块数据，然后存储到 PostgreSQL数据库中；
- 用户通过GraphNode提供的GraphQL接口，来查询感兴趣的数据；
便于理解：
- 区块链数据 = 河水中的鱼
- SubGraph = 你设计捞网的形状，决定打捞大鱼还是小鱼；
- GraphNode = 打捞的工人，用捞网去小河中捞鱼，捞到的鱼放到箱子里；
- GraphQL查询 = 从箱子中找到你想要的鱼；

2. 在线部署

Subgraph Studio 是 The Graph 官方提供的图形化工具，用来创建、测试、部署和管理 Subgraph 的 Web 平台。

官方教程：https://thegraph.com/docs/zh/subgraphs/quick-start/

我们在此平台上来监听Counter合约的事件，监听事件包括：SetNumber和Increment，来监听number的变化；

准备条件

加密钱包：为了登录Web平台
已部署的合约地址：用于监控合约的事件，注意该合约存在事件；我已在Ethereum Sepolia网络上成功部署和验证的Counter合约；
安装Node.js：推荐安装v23.11.0。用于安装Graph 客户端或相关依赖包；安装工具支持npm，yarn和 pnpm

2.1 创建subgraph

使用metamask钱包登录网站：https://thegraph.com/studio/
创建一个子图：Counter子图。创建成功后，在右栏提供了具体的创建步骤；

2.2 安装graph客户端

在本地电脑上安装graph客户端

# npm安装graph客户端
$ npm install -g @graphprotocol/graph-cli@latest
npm warn deprecated inflight@1.0.6: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful.
npm warn deprecated rimraf@2.7.1: Rimraf versions prior to v4 are no longer supported
npm warn deprecated glob@7.2.3: Glob versions prior to v9 are no longer supported
added 422 packages in 22s
86 packages are looking for funding
  run `npm fund` for details

# 查看客户端版本
$ graph --version
@graphprotocol/graph-cli/0.97.0 win32-x64 node-v23.11.0

2.3 初始化subgraph

根据执行输入参数

选择sepolia网络，回车，回车，回车
输入合约地址：该合约需要验证通过，才能解析成功其中的ABI信息，否则要自行执行ABI的绝对路径。这是我验证通过的Counter合约地址
一路回车，使用默认参数；

$ graph init counter

√ Network · Ethereum Sepolia Testnet · sepolia · https://sepolia.etherscan.io  # 完整输入Ethereum Sepolia Testnet，选择sepolia网络
√ Source · Smart Contract · ethereum                # 回车
√ Subgraph slug · counter                   # 回车
√ Directory to create the subgraph in · counter         # 回车
√ Contract address · 0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856 # 输入验证通过的合约地址
√ Fetching ABI from Sourcify API...
√ Fetching ABI from Contract API...
√ Fetching start block from Contract API...
√ Fetching contract name from Contract API...
√ Start block · 8310332                     # 回车，确认部署合约的区块号
? Contract name » counter                   # 回车
√ Contract name · counter
√ Index contract events as entities (Y/n) · true        # 回车
  Generate subgraph
  Write subgraph to directory
√ Create subgraph scaffold
√ Initialize networks config
√ Initialize subgraph repository
√ Install dependencies with npm install
√ Generate ABI and schema types with npm run codegen
√ Add another contract? (y/N) · false               # 回车

Subgraph counter created in counter
Next steps:
  1. Run `graph auth` to authenticate with your deploy key.
  2. Type `cd counter` to enter the subgraph.
  3. Run `npm run deploy` to deploy the subgraph.
Make sure to visit the documentation on https://thegraph.com/docs/ for further information.

2.4 授权

授权码在web端中查找 deploy key

$ graph auth 635702bb8e772ac010c612105bd4b2f4
Deploy key set for https://api.studio.thegraph.com/deploy/

2.5 生成和编译

三个核心文件：

schema.graphql：定义解析数据的结构，即作为存储到PostgreSQL的实体结构，也是前端查询接口的传参；
subgraph.yaml：定义数据来源和处理规则；告诉GraphNode监听哪些合约，从哪个区块开始，匹配哪些事件，调用哪个处理函数等；
mapping.ts：定义事件的处理逻辑，将解析数据转换为实体存入PostgreSQL;

# 进入初始化项目目录
$ cd counter/

# 生成和编译
$ graph codegen && graph build
  Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4
√ Apply migrations
√ Load subgraph from subgraph.yaml                      # 数据来源和处理规则
  Load contract ABI from abis\counter.json
√ Load contract ABIs
  Generate types for contract ABI: counter (abis\counter.json)
  Write types to generated\counter\counter.ts
√ Generate types for contract ABIs
√ Generate types for data source templates
√ Load data source template ABIs
√ Generate types for data source template ABIs
√ Load GraphQL schema from schema.graphql                   # 解析数据的实体
  Write types to generated\schema.ts
√ Generate types for GraphQL schema

Types generated successfully                            # 生成成功

  Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4
√ Apply migrations
√ Load subgraph from subgraph.yaml
  Compile data source: counter => build\counter\counter.wasm
√ Compile subgraph
  Copy schema file build\schema.graphql
  Write subgraph file build\counter\counter.json
  Write subgraph manifest build\subgraph.yaml
√ Write compiled subgraph to build\

Build completed: build\subgraph.yaml                        # 编译完成

2.5.1 schema.graphql文件

生成的schema.graphql文件内容

定义解析数据的结构，即作为存储到PostgreSQL的实体结构，也是前端查询接口的传参；

type Increment @entity(immutable: true) {   # @entity 表示这是需要被GraphNode存储到PostgreSQL的数据
  id: Bytes!                    # 所有 Entity 都需要有一个 id 字段
  sender: Bytes! # address
  newValue: BigInt! # uint256
  blockNumber: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}

type SetNumber @entity(immutable: true) {
  id: Bytes!
  sender: Bytes! # address
  newNumber: BigInt! # uint256
  blockNumber: BigInt!
  blockTimestamp: BigInt!
  transactionHash: Bytes!
}

2.5.2 subgraph.yaml文件

定义数据来源和处理规则；告诉GraphNode监听哪些合约，从哪个区块开始，匹配哪些事件，调用哪个处理函数等；

specVersion: 1.3.0
indexerHints:
  prune: auto
schema:
  file: ./schema.graphql
dataSources:                    # 要监听的链上合约及其事件
  - kind: ethereum
    name: counter
    network: sepolia
    source:
      address: "0xB78473a261797b9Fa4a18adff4Ad89B2b94B8856"
      abi: counter              # 对应事件的 ABI 文件，用于解析日志
      startBlock: 8310332           # 指定从哪个区块开始监听（提升效率）
    mapping:
      kind: ethereum/events
      apiVersion: 0.0.9
      language: wasm/assemblyscript
      entities:
        - Increment
        - SetNumber
      abis:
        - name: counter
          file: ./abis/counter.json
        eventHandlers:              # 指定事件和处理函数的映射关系
        - event: Increment(indexed address,uint256)
          handler: handleIncrement
        - event: SetNumber(indexed address,uint256)
          handler: handleSetNumber
      file: ./src/counter.ts    # 指定映射逻辑所在的 TypeScript 文件

2.5.3 mapping.ts

该案例的mapping.ts 对应为 counter/src/counter.ts；

定义事件的处理逻辑，将解析数据转换为实体存入PostgreSQL;

import {
  Increment as IncrementEvent,
  SetNumber as SetNumberEvent
} from "../generated/counter/counter"
import { Increment, SetNumber } from "../generated/schema"

export function handleIncrement(event: IncrementEvent): void {
  let entity = new Increment(           // 监听到 IncrementEvent 后，创建一个entity实体。
    event.transaction.hash.concatI32(event.logIndex.toI32())
  )
  entity.sender = event.params.sender       // 利用事件参数填充字段
  entity.newValue = event.params.newValue

  entity.blockNumber = event.block.number
  entity.blockTimestamp = event.block.timestamp
  entity.transactionHash = event.transaction.hash

  entity.save()                 // 然后 .save() 保存进数据库。
}

export function handleSetNumber(event: SetNumberEvent): void {
  let entity = new SetNumber(
    event.transaction.hash.concatI32(event.logIndex.toI32())
  )
  entity.sender = event.params.sender
  entity.newNumber = event.params.newNumber

  entity.blockNumber = event.block.number
  entity.blockTimestamp = event.block.timestamp
  entity.transactionHash = event.transaction.hash

  entity.save()
}

2.6 部署

将三个核心文件上传IPFS，并部署Graph node

$ graph deploy counter

# 正确结果
Which version label to use? (e.g. "v0.0.1") · v0.0.1        # 输入版本标签，用于标识本次部署的子图版本
  Skip migration: Bump mapping apiVersion from 0.0.1 to 0.0.2
  Skip migration: Bump mapping apiVersion from 0.0.2 to 0.0.3
  Skip migration: Bump mapping apiVersion from 0.0.3 to 0.0.4
  Skip migration: Bump mapping apiVersion from 0.0.4 to 0.0.5
  Skip migration: Bump mapping apiVersion from 0.0.5 to 0.0.6
  Skip migration: Bump manifest specVersion from 0.0.1 to 0.0.2
  Skip migration: Bump manifest specVersion from 0.0.2 to 0.0.4

  # 编译输出的关键文件（已准备部署）
  Write subgraph file build\counter\counter.json    # subgraph.yaml 编译后的 JSON 格式配置
  Write subgraph manifest build\subgraph.yaml       # 拷贝原始 manifest 文件用于 build 目录中的部署引用
√ Write compiled subgraph to build\         # 编译完成，所有核心文件写入 build 目录

  # 将核心文件上传到 IPFS（去中心化内容地址存储）
  Add file to IPFS build\schema.graphql         # GraphQL 实体结构定义（决定可查询字段）
                .. QmezFjzFxkKzgjYZzNgM67kEbwFWFqYSCjrGmXwLSsfas5# IPFS文件的唯一哈希值，保证唯一防篡改
  Add file to IPFS build\counter\counter.json       # 索引说明书（合约地址、处理事件、mapping 指向等）
                .. QmUp4K2wbtfL6BS6RkcPmqMrEgzDJFbiG8spBtVFY7cPCX
  Add file to IPFS build\counter\counter.wasm       # 编译后的 mapping.ts 文件（事件处理逻辑）
                .. QmU7rqqieWR3v8rcxwtEvDkWM12ymA4E5bK5eHtpf2zCUa
√ Upload subgraph to IPFS                                                           # 上传成功！

Build completed: QmQ3iiVTZByx28jUuN1nXPAHr2JcwxgjfAVjDa9gYvZhyc # 整个子图的 IPFS 根哈希（代表本次部署的唯一标识）

- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl
\ Deploying to Graph node https://api.studio.thegraph.com/depl
| Deploying to Graph node https://api.studio.thegraph.com/depl
/ Deploying to Graph node https://api.studio.thegraph.com/depl
- Deploying to Graph node https://api.studio.thegraph.com/depl    # 部署到graph node节点
Deployed to https://thegraph.com/studio/subgraph/counter      # 部署到studio中