Fetch ERC-1967 proxy implementation in generate CLI command

packages/cli/src/plugins/blockExplorer.ts

@@ -1,12 +1,79 @@
 import { camelCase } from 'change-case'
-import type { Address } from 'viem'
+import {
+  http,
+  type Address,
+  createClient,
+  isAddress,
+  isAddressEqual,
+  slice,
+  zeroAddress,
+} from 'viem'
+import { getStorageAt } from 'viem/actions'
 import { z } from 'zod'
 
 import type { ContractConfig } from '../config.js'
 import { fromZodError } from '../errors.js'
 import type { Compute } from '../types.js'
 import { fetch } from './fetch.js'
 
+export const rpcUrls = {
+  [1]: 'https://cloudflare-eth.com',
+
+  [5]: 'https://rpc.ankr.com/eth_goerli',
+
+  [10]: 'https://mainnet.optimism.io',
+
+  [56]: 'https://rpc.ankr.com/bsc',
+
+  [97]: 'https://data-seed-prebsc-1-s1.bnbchain.org:8545',
+
+  [100]: 'https://rpc.gnosischain.com',
+
+  [128]: 'undefined',
+
+  [137]: 'https://polygon-rpc.com',
+
+  [250]: 'https://rpc.ankr.com/fantom',
+
+  [252]: 'https://rpc.frax.com',
+
+  [256]: 'undefined',
+
+  [420]: 'https://goerli.optimism.io',
+
+  [2522]: 'https://rpc.testnet.frax.com',
+
+  [4002]: 'https://rpc.testnet.fantom.network',
+
+  [8453]: 'https://mainnet.base.org',
+
+  [17000]: 'https://ethereum-holesky-rpc.publicnode.com',
+
+  [42161]: 'https://arb1.arbitrum.io/rpc',
+
+  [42220]: 'https://forno.celo.org',
+
+  [43113]: 'https://api.avax-test.network/ext/bc/C/rpc',
+
+  [43114]: 'https://api.avax.network/ext/bc/C/rpc',
+
+  [44787]: 'https://alfajores-forno.celo-testnet.org',
+
+  [80001]: 'https://rpc.ankr.com/polygon_mumbai',
+
+  [81457]: 'https://rpc.blast.io',
+
+  [84532]: 'https://sepolia.base.org',
+
+  [421613]: 'https://goerli-rollup.arbitrum.io/rpc',
+
+  [421614]: 'https://sepolia-rollup.arbitrum.io/rpc',
+
+  [11155111]: 'https://rpc.sepolia.org',
+
+  [11155420]: 'https://sepolia.optimism.io',
+}
+
 export type BlockExplorerConfig = {
   /**
    * API key for block explorer. Appended to the request URL as query param `&apikey=${apiKey}`.
@@ -38,6 +105,10 @@ export type BlockExplorerConfig = {
    * Name of source.
    */
   name?: ContractConfig['name'] | undefined
+  /**
+   *  Chain id to use for fetching on-chain info of contract (e.g. implementation address)
+   */
+  chainId?: number | undefined
 }
 
 const BlockExplorerResponse = z.discriminatedUnion('status', [
@@ -69,6 +140,7 @@ export function blockExplorer(config: BlockExplorerConfig) {
       return Object.values(address)[0]!
     },
     name = 'Block Explorer',
+    chainId,
   } = config
 
   return fetch({
@@ -88,13 +160,60 @@ export function blockExplorer(config: BlockExplorerConfig) {
       if (parsed.data.status === '0') throw new Error(parsed.data.result)
       return parsed.data.result
     },
-    request({ address }) {
+    async request({ address }) {
       if (!address) throw new Error('address is required')
+      const normalizedAddress = getAddress({ address })
+      const makeUrl = (address: Address) =>
+        `${baseUrl}?module=contract&action=getabi&address=${address}${apiKey ? `&apikey=${apiKey}` : ''}`
+
+      const implementationAddress = await getImplementationAddress({
+        address: normalizedAddress,
+        chainId,
+      })
+      if (implementationAddress) {
+        return {
+          url: makeUrl(implementationAddress),
+        }
+      }
+
       return {
-        url: `${baseUrl}?module=contract&action=getabi&address=${getAddress({
-          address,
-        })}${apiKey ? `&apikey=${apiKey}` : ''}`,
+        url: makeUrl(normalizedAddress),
       }
     },
   })
 }
+
+async function getImplementationAddress({
+  address,
+  chainId,
+}: { address: Address; chainId: number | undefined }): Promise<
+  Address | undefined
+> {
+  if (!chainId) return undefined
+
+  const rpcUrl: string | undefined = (rpcUrls as any)[chainId]
+  if (!rpcUrl) return undefined
+
+  const client = createClient({
+    transport: http(rpcUrl),
+  })
+
+  // ERC-1967 Implementation Slot
+  const implementationSlot =
+    '0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc'
+  const implementationSlotContent = await getStorageAt(client, {
+    address,
+    slot: implementationSlot,
+  })
+
+  if (!implementationSlotContent) return undefined
+
+  const implementationAddress = slice(implementationSlotContent, 12)
+  if (
+    !isAddress(implementationAddress) ||
+    isAddressEqual(implementationAddress, zeroAddress)
+  )
+    return undefined
+
+  return implementationAddress
+}

packages/cli/src/plugins/etherscan.ts

@@ -115,5 +115,6 @@ export function etherscan<chainId extends ChainId>(
       return contractAddress
     },
     name: 'Etherscan',
+    chainId,
   })
 }