Replace Etherscan ABI lookups with Sourcify

Etherscan requires an API key for ABI lookup and other operations.
Sourcify (https://sourcify.dev) is an open-source decentralized alternative.

Author: 0237h

packages/cli/src/command-helpers/abi.ts

@@ -7,6 +7,30 @@ import { withSpinner } from './spinner';
 
 const logger = debugFactory('graph-cli:abi-helpers');
 
+export const loadAbiFromSourcify = async (
+  ABICtor: typeof ABI,
+  network: string,
+  address: string,
+): Promise<ABI> =>
+  await withSpinner(
+    `Fetching ABI from Sourcify`,
+    `Failed to fetch ABI from Sourcify`,
+    `Warnings while fetching ABI from Sourcify`,
+    async () => {
+      const chainId = await getSourcifyChainId(network);
+      const result = await fetch(`https://repo.sourcify.dev/contracts/full_match/${chainId}/${address}/metadata.json`);
+      const json = await result.json();
+
+      // Etherscan returns a JSON object that has a `status`, a `message` and
+      // a `result` field. The `status` is '0' in case of errors and '1' in
+      // case of success
+      if (result.ok) {
+        return new ABICtor('Contract', undefined, immutable.fromJS(json.output.abi));
+      }
+      throw new Error('ABI not found, try loading it from a local file');
+    },
+  );
+
 export const loadAbiFromEtherscan = async (
   ABICtor: typeof ABI,
   network: string,
@@ -200,6 +224,19 @@ export const loadAbiFromBlockScout = async (
     },
   );
 
+const getSourcifyChainId = async (network: string) => {
+  const result = await fetch('https://sourcify.dev/server/chains');
+  const json = await result.json();
+
+  // Can fail if network name doesn't follow https://chainlist.org name convention
+  const match = json.find((e: any) => e.name.toLowerCase().includes(network.replace('-', ' ')));
+
+  if (match)
+    return match.chainId;
+  else
+    throw new Error(`Could not find chain id for "${network}"`);
+};
+
 const getEtherscanLikeAPIUrl = (network: string) => {
   switch (network) {
     case 'mainnet':
@@ -334,8 +371,6 @@ const getEtherscanLikeAPIUrl = (network: string) => {
       return 'https://api.routescan.io/v2/network/testnet/evm/9728/etherscan/api';
     case 'fuse-testnet':
       return 'https://explorer.fusespark.io/api';
-    case 'rootstock-testnet':
-      return 'https://rootstock-testnet.blockscout.com/api';
     default:
       return `https://api-${network}.etherscan.io/api`;
   }
@@ -484,12 +519,6 @@ const getPublicRPCEndpoint = (network: string) => {
       return 'https://testnet.bnb.boba.network';
     case 'fuse-testnet':
       return 'https://rpc.fusespark.io';
-    case 'rootstock-testnet':
-      return 'https://public-node.testnet.rsk.co';
-    case 'kaia':
-      return 'https://public-en.node.kaia.io';
-    case 'kaia-testnet':
-      return 'https://public-en.kairos.node.kaia.io';
     default:
       throw new Error(`Unknown network: ${network}`);
   }

packages/cli/src/commands/init.ts

@@ -6,7 +6,7 @@ import { filesystem, prompt, system } from 'gluegun';
 import { Args, Command, Flags, ux } from '@oclif/core';
 import {
   loadAbiFromBlockScout,
-  loadAbiFromEtherscan,
+  loadAbiFromSourcify,
   loadContractNameForAddress,
   loadStartBlockForContract,
 } from '../command-helpers/abi';
@@ -292,7 +292,7 @@ export default class InitCommand extends Command {
             if (network === 'poa-core') {
               abi = await loadAbiFromBlockScout(ABI, network, fromContract);
             } else {
-              abi = await loadAbiFromEtherscan(ABI, network, fromContract);
+              abi = await loadAbiFromSourcify(ABI, network, fromContract);
             }
           } catch (e) {
             process.exitCode = 1;
@@ -544,7 +544,7 @@ async function processInitForm(
     }
   | undefined
 > {
-  let abiFromEtherscan: EthereumABI | undefined = undefined;
+  let abiFromSourcify: EthereumABI | undefined = undefined;
 
   try {
     const { protocol } = await prompt.ask<{ protocol: ProtocolName }>({
@@ -705,17 +705,11 @@ async function processInitForm(
 
           const ABI = protocolInstance.getABI();
 
-          // Try loading the ABI from Etherscan, if none was provided
+          // Try loading the ABI from Sourcify, if none was provided
           if (protocolInstance.hasABIs() && !initAbi) {
-            if (network === 'poa-core') {
-              abiFromEtherscan = await retryWithPrompt(() =>
-                loadAbiFromBlockScout(ABI, network, value),
-              );
-            } else {
-              abiFromEtherscan = await retryWithPrompt(() =>
-                loadAbiFromEtherscan(ABI, network, value),
-              );
-            }
+            abiFromSourcify = await retryWithPrompt(() =>
+              loadAbiFromSourcify(ABI, network, value),
+            );
           }
           // If startBlock is not set, try to load it.
           if (!initStartBlock) {
@@ -765,11 +759,11 @@ async function processInitForm(
         skip: () =>
           !protocolInstance.hasABIs() ||
           initFromExample !== undefined ||
-          abiFromEtherscan !== undefined ||
+          abiFromSourcify !== undefined ||
           isSubstreams ||
           !!initAbiPath,
         validate: async (value: string) => {
-          if (initFromExample || abiFromEtherscan || !protocolInstance.hasABIs()) {
+          if (initFromExample || abiFromSourcify || !protocolInstance.hasABIs()) {
             return true;
           }
 
@@ -791,7 +785,7 @@ async function processInitForm(
           }
         },
         result: async (value: string) => {
-          if (initFromExample || abiFromEtherscan || !protocolInstance.hasABIs()) {
+          if (initFromExample || abiFromSourcify || !protocolInstance.hasABIs()) {
             return null;
           }
           const ABI = protocolInstance.getABI();
@@ -853,7 +847,7 @@ async function processInitForm(
     ]);
 
     return {
-      abi: abiFromEtherscan || abiFromFile,
+      abi: abiFromSourcify || abiFromFile,
       protocolInstance,
       subgraphName,
       directory,