Friend Tech 项目信息
- 项目名称：Friend Tech
- 项目描述：Friend Tech 是一个去中心化社交平台，允许用户将自己代币化。
- 公链：Base
- 合约地址： 0xCF205808Ed36593aa40a44F10c7f7C2F67d4A4d4
- 网址：https://www.friend.tech
yarn add @graphprotocol/graph-cli
yarn add @graphprotocol/graph-ts首先我们可以手动下载合约的abi文件到本地，加速创建过程，合约abi地址：https://basescan.org/address/0xCF205808Ed36593aa40a44F10c7f7C2F67d4A4d4#code
将abi文件内容写入到ft.json文件中
➜ cd tmp
➜ vim ft.json
➜ cat ft.json
[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],
...首先安装完 graph-cli 工具后，我们在本地创建一个新的目录，然后在终端使用命令graph init初始化一个新的subgraph项目
graph cli 客户端会引导你一步步创建，需要自定义的参数会按照不同的客户端版本有所不同，但是大致如下:
➜ tmp graph init
✔ Protocol · ethereum
✔ Product for which to initialize · subgraph-studio
✔ Subgraph slug · friend-tech
✔ Directory to create the subgraph in · friend-tech
✔ Ethereum network · mainnet # evm兼容的公链都可以选mainnet
✔ Contract address · 0xCF205808Ed36593aa40a44F10c7f7C2F67d4A4d4 # 合约地址
✖ Failed to fetch ABI from Etherscan: request to https://api.etherscan.io/api?module=contract&action=getabi&address=0xCF205808Ed36593aa40a44F10c7f7C2F67d4A4d4 failed, reason: read ECONNRESET
✖ Failed to fetch Start Block: Failed to fetch contract creation transaction hash
✔ ABI file (path) · ./ft.json # 这里填我们手动下载的abi文件
✔ Start Block · 2430440 # 合约创建的区块高度
✔ Contract Name · Contract
✔ Index contract events as entities (Y/n) · true
Generate subgraph
Write subgraph to directory
✔ Create subgraph scaffold
✔ Initialize networks config
✔ Initialize subgraph repository
✖ Failed to install dependencies: Command failed: yarn # 有报错不要仅 下面教大家如何解决获取合约部署区块高度
最后 yarn 或者 npm 会根据初始化流程安装一些具体项目依赖，其中可能会有一个 concat-stream github 仓库版本不存在特定分支feat/smaller的报错，我们可以使用package.json 里面的resolutions 将有问题的分支重定向到我们chainbase的分支：
"resolutions": {
"concat-stream": "https://github.com/chainbase-labs/concat-stream#1.4.x"
},
最后重新执行一次 yarn 安装确认项目初始化依赖是否正常
yarn && yarn install
graph init 完成后默认就会为我们自动生成上面的框架代码，只需要修改几个文件就可以达到我们想索引 bayc 合约的目地。接下来让我们一步步了解各个文件的作用，并尝试编写出能索引合约数据的subgraph
- subgraph.yaml 第一步是需要定义我们的数据源，也就是告诉 subgraph 具体索引什么智能合约，合约地址、网络、abi和索引触发的一些处理器等
specVersion: 0.0.5
schema:
file: ./schema.graphql
dataSources:
- kind: ethereum
name: Contract
network: mainnet
source:
address: "0xCF205808Ed36593aa40a44F10c7f7C2F67d4A4d4"
abi: Contract
startBlock: 2430440
mapping:
kind: ethereum/events
apiVersion: 0.0.7
language: wasm/assemblyscript
entities:
- OwnershipTransferred
- Trade
abis:
- name: Contract
file: ./abis/Contract.json
eventHandlers:
- event: Trade(address,address,bool,uint256,uint256,uint256,uint256,uint256)
handler: handleTrade
file: ./src/contract.tsThe Graph 允许我们在EVM 链上定义三种处理函数：事件处理函数、调用处理函数和块处理函数。详细可以参考：Subgraph Manifest
这里核心的处理函数就是eventHandlers，它定义了我们从区块链事件中怎么索引数据。拿Transfer事件举例：
- 每当一个 NFT 从一个地址转移到另外一个地址时，就会触发此事件。它会记录NFT 的前所有者、新所有者和具体的 NFT TOKEN ID
- 我们希望能从初始区块开始记录transfer，这样我们就能记录完整的BAYC NFT完整的所有权历史
- 此外，在后面定义Transfer ID 实体时如果将其标记为不可变，那么查询速度会更快
- schema.garphql schema定义了我们需要存储的数据类型，也就是最终存储到 postgresql 的字段，后续也可以通过这些字段来自定义查询语句
type Protocol @entity {
id: ID!
userCount: Int!
protocolRevenue: BigDecimal!
accountRevenue: BigDecimal!
tradeVolume: BigDecimal!
totalTrades: Int!
}
type Account @entity {
id: ID!
holdersCount: Int!
keySupply: BigDecimal!
holders: [Holder!]! @derivedFrom(field: "account")
}
type Holder @entity {
id: ID!
account: Account!
keysOwned: BigDecimal!
}
type Trade @entity {
id: ID!
trader: Bytes!
subject: Bytes!
isBuy: Boolean!
shareAmount: BigDecimal!
ethAmount: BigDecimal!
protocolEthAmount: BigDecimal!
subjectEthAmount: BigDecimal!
supply: BigDecimal!
}这里有几点需要注意，每个实体需要有 @entity 指令。还需要有一个 ID字段，该字段的唯一值必须适用于所有相同类型的实体。下面是一些常见的数据类型，详细可以参考：类型
- contract.ts(friendtech-shares-v-1.ts) 这个文件是我们的处理器，也就是我们从区块链事件中索引数据的具体逻辑，这里我们只需要关注 handleTrade 函数，它会在每次 Transfer 事件触发时被调用，我们可以在这里定义我们需要索引的数据
import { BigDecimal, crypto, BigInt, Bytes } from '@graphprotocol/graph-ts'
import {
Trade as TradeEvent,
} from '../../../friend-tech/generated/FriendtechSharesV1/FriendtechSharesV1'
import { Trade, Protocol, Account, Holder } from '../../../friend-tech/generated/schema'
function getOrCreateAccount(accountId: string): Account {
let account = Account.load(accountId)
if (account == null) {
account = new Account(accountId)
account.holdersCount = 0
account.keySupply = BigDecimal.fromString('0')
account.save()
}
return account as Account
}
function getOrCreateHolder(holderId: string, account: Account): Holder {
let holder = Holder.load(holderId)
if (holder == null) {
holder = new Holder(holderId)
holder.keysOwned = BigDecimal.fromString('0')
holder.account = account.id
holder.save()
// Update account's holders count
account.holdersCount = account.holdersCount + 1
account.save()
}
return holder as Holder
}
function getOrCreateProtocol(protocolId: string): Protocol {
let protocol = Protocol.load(protocolId)
if (protocol == null) {
protocol = new Protocol(protocolId)
protocol.userCount = 0
protocol.protocolRevenue = BigDecimal.fromString('0')
protocol.accountRevenue = BigDecimal.fromString('0')
protocol.tradeVolume = BigDecimal.fromString('0')
protocol.totalTrades = 0
protocol.save()
}
return protocol as Protocol
}
export function handleTrade(event: TradeEvent): void {
let trade = new Trade(event.transaction.hash.toHex() + "-" + event.logIndex.toString())
trade.trader = event.params.trader
trade.subject = event.params.subject
trade.isBuy = event.params.isBuy
trade.shareAmount = event.params.shareAmount.toBigDecimal()
trade.ethAmount = event.params.ethAmount.toBigDecimal()
trade.protocolEthAmount = event.params.protocolEthAmount.toBigDecimal()
trade.subjectEthAmount = event.params.subjectEthAmount.toBigDecimal()
trade.supply = event.params.supply.toBigDecimal()
trade.save()
let protocol = getOrCreateProtocol('1') // Assuming there is only one protocol
protocol.tradeVolume = protocol.tradeVolume.plus(trade.ethAmount)
protocol.totalTrades = protocol.totalTrades + 1
protocol.protocolRevenue = protocol.protocolRevenue.plus(trade.protocolEthAmount)
protocol.accountRevenue = protocol.accountRevenue.plus(trade.subjectEthAmount)
protocol.userCount = protocol.userCount + 1 // This logic may need adjustment based on your specific definition of a user
protocol.save()
let accountId = event.params.trader.toHex()
let account = getOrCreateAccount(accountId)
account.keySupply = account.keySupply.plus(trade.shareAmount) // Assuming shareAmount corresponds to keys
account.save()
let holderId = event.transaction.from.toHex()
let holder = getOrCreateHolder(holderId, account)
holder.keysOwned = holder.keysOwned.plus(trade.shareAmount) // Update the keys owned by this holder
holder.save()
}到这里，我们已经完整开发完成了一个简单的subgraph，接下来就可以编译我们的代码并且部署 subgraph 。
- graph codegen
每次修改完subgraph.yaml 和scheme.graphql文件后都要执行 codegen，用来生成generated目录中对应的AssemblyScript文件：
➜ friend-tech git:(main) ✗ graph codegen
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
Load contract ABI from abis/Contract.json
✔ Load contract ABIs
Generate types for contract ABI: Contract (abis/Contract.json)
Write types to generated/Contract/Contract.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
Write types to generated/schema.ts
✔ Generate types for GraphQL schema
Types generated successfully- graph build 将subgraph变成成WebAssembly，等待部署
➜ friend-tech git:(main) ✗ 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
Compile data source: Contract => build/Contract/Contract.wasm
✔ Compile subgraph
Copy schema file build/schema.graphql
Write subgraph file build/Contract/abis/Contract.json
Write subgraph manifest build/subgraph.yaml
✔ Write compiled subgraph to build/
Build completed: build/subgraph.yaml- 部署我们的子图 启动我们的本地docker实例（注意修改node.toml中的rpc地址，需要api key，如果没有可以到chainbase后台创建）
➜ cd docker
➜ vim node.toml(*修改RPC地址*)
➜ cd docker-compose up部署成功后，我们稍等几分钟，本都数据库中应该就有我们的索引数据了
使用另外一个终端，部署我们的子图
cd ../friend-tech
yarn create-local
yarn deploy-local 部署成功后，可以在docker运行日志里面看到我们新部署的子图deployment_id
本地打开graphql查询窗口
http://127.0.0.1:8000/subgraphs/id/QmQVk7YWVwHRhxHvZyqyLxT8Ue4hc2TWtk439xocMeNjZF
