First iteration of a Polygon block explorer smart contract verifier

helpers/contracts-helpers.ts

@@ -24,7 +24,8 @@ import { Artifact } from 'hardhat/types';
 import { Artifact as BuidlerArtifact } from '@nomiclabs/buidler/types';
 import { verifyContract } from './etherscan-verification';
 import { getIErc20Detailed } from './contracts-getters';
-import { usingTenderly } from './tenderly-utils';
+import { usingTenderly, verifyAtTenderly } from './tenderly-utils';
+import { usingPolygon, verifyAtPolygon } from './polygon-utils';
 
 export type MockTokenMap = { [symbol: string]: MintableERC20 };
 
@@ -99,17 +100,14 @@ export const withSaveAndVerify = async <ContractType extends Contract>(
   await waitForTx(instance.deployTransaction);
   await registerContractInJsonDb(id, instance);
   if (usingTenderly()) {
-    console.log();
+    await verifyAtTenderly(id, instance);
-    console.log('Doing Tenderly contract verification of', id);
-    await (DRE as any).tenderlyRPC.verify({
-      name: id,
-      address: instance.address,
-    });
-    console.log(`Verified ${id} at Tenderly!`);
-    console.log();
   }
   if (verify) {
-    await verifyContract(instance.address, args);
+    if (usingPolygon()) {
+      await verifyAtPolygon(id, instance, args);
+    } else {
+      await verifyContract(instance.address, args);
+    }
   }
   return instance;
 };

helpers/polygon-utils.ts

@@ -0,0 +1,103 @@
+import axios from 'axios';
+import { Contract } from 'ethers/lib/ethers';
+import { HardhatRuntimeEnvironment } from 'hardhat/types';
+import { source } from 'lowdb/adapters/FileSync';
+import { file } from 'tmp-promise';
+import { DRE } from './misc-utils';
+import { ePolygonNetwork } from './types';
+
+const TASK_FLATTEN_GET_FLATTENED_SOURCE = 'flatten:get-flattened-sources';
+const TASK_COMPILE_SOLIDITY_GET_SOURCE_PATHS = 'compile:solidity:get-source-paths';
+
+/* Polygon Helpers */
+
+export const usingPolygon = () =>
+  DRE && Object.keys(ePolygonNetwork).includes((DRE as HardhatRuntimeEnvironment).network.name);
+
+/* Polygon Verifier */
+
+const SOLIDITY_PRAGMA = 'pragma solidity';
+const LICENSE_IDENTIFIER = 'License-Identifier';
+const EXPERIMENTAL_ABIENCODER = 'pragma experimental ABIEncoderV2;';
+
+// Remove lines at "text" that includes "matcher" string, but keeping first "keep" lines
+const removeLines = (text: string, matcher: string, keep = 0): string => {
+  let counter = keep;
+  return text
+    .split('\n')
+    .filter((line) => {
+      const match = !line.includes(matcher);
+      if (match === false && counter > 0) {
+        counter--;
+        return true;
+      }
+      return match;
+    })
+    .join('\n');
+};
+
+// Try to find the path of a Contract by name of the file without ".sol"
+const findPath = async (id: string): Promise<string> => {
+  const paths = await DRE.run(TASK_COMPILE_SOLIDITY_GET_SOURCE_PATHS);
+  const path = paths.find((x) => {
+    const t = x.split('/');
+    return t[t.length - 1].split('.')[0] == id;
+  });
+
+  if (!path) {
+    throw Error('Missing path for contract name: ${id}');
+  }
+
+  return path;
+};
+
+// Hardhat Flattener, similar to truffle flattener
+const hardhatFlattener = async (filePath: string) =>
+  await DRE.run(TASK_FLATTEN_GET_FLATTENED_SOURCE, { files: [filePath] });
+
+// Verify a smart contract at Polygon Matic network via a GET request to the block explorer
+export const verifyAtPolygon = async (
+  id: string,
+  instance: Contract,
+  args: (string | string[])[]
+) => {
+  /*
+    ${net == mumbai or mainnet}
+    https://explorer-${net}.maticvigil.com/api
+    ?module=contract
+    &action=verify
+    &addressHash={addressHash}
+    &name={name}
+    &compilerVersion={compilerVersion}
+    &optimization={false}
+    &contractSourceCode={contractSourceCode}
+  */
+  try {
+    const net = (DRE as HardhatRuntimeEnvironment).network.name;
+    const filePath = await findPath(id);
+    const flattenSourceCode = await hardhatFlattener(filePath);
+
+    // Remove pragmas and license identifier after first match, required by block explorers like explorer-mainnet.maticgivil.com or Etherscan
+    const cleanedSourceCode = removeLines(
+      removeLines(removeLines(flattenSourceCode, LICENSE_IDENTIFIER, 1), SOLIDITY_PRAGMA, 1),
+      EXPERIMENTAL_ABIENCODER,
+      1
+    );
+    const response = await axios.get(`https://explorer-${net}.maticvigil.com/api`, {
+      params: {
+        module: 'contract',
+        action: 'verify',
+        addressHash: instance.address,
+        name: id,
+        compilerVersion: 'v0.6.12+commit.27d51765',
+        optimization: 'true',
+        contractSourceCode: cleanedSourceCode,
+      },
+    });
+    console.log(response);
+    console.log(JSON.stringify(response, null, 2));
+  } catch (error) {
+    console.error('[Polygon Verify] Error:', error.toString());
+    throw error;
+  }
+};

helpers/tenderly-utils.ts

@@ -1,3 +1,4 @@
+import { Contract } from 'ethers';
 import { HardhatRuntimeEnvironment } from 'hardhat/types';
 import { DRE } from './misc-utils';
 
@@ -5,3 +6,14 @@ export const usingTenderly = () =>
   DRE &&
   ((DRE as HardhatRuntimeEnvironment).network.name.includes('tenderly') ||
     process.env.TENDERLY === 'true');
+
+export const verifyAtTenderly = async (id: string, instance: Contract) => {
+  console.log();
+  console.log('Doing Tenderly contract verification of', id);
+  await (DRE as any).tenderlyRPC.verify({
+    name: id,
+    address: instance.address,
+  });
+  console.log(`Verified ${id} at Tenderly!`);
+  console.log();
+};