app.js

import express from 'express';
import { writeFileSync, readFileSync } from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import hardhat from 'hardhat';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const app = express();
app.use(express.json({ limit: '50mb' }));
app.use(express.urlencoded({ limit: '50mb', extended: true }));

async function compileContract(contractSourceCode){
  const filePath = path.join(__dirname, '/artifacts/SolidityVerifier.sol');
  writeFileSync(filePath, contractSourceCode, (err) => {
    if (err) {
      console.error('Error writing to file:', err)
    } else {
      console.log('File written successfully!');
    }
  })

  await hardhat.run('compile');
}

app.post("/compile-contract", async (req,res) => {
  let response = { object: undefined, errors: [] }
  try {
    let { contractSourceCode } = req.body;

    await compileContract(contractSourceCode)
    let file = readFileSync("./artifacts/hardhat/artifacts/SolidityVerifier.sol/UltraVerifier.json", "utf8")
    let json_file = JSON.parse(file)
    let contractBytecode = json_file.bytecode
    response.object = {
      contractBytecode
    }
  } catch (e) {
    console.log(e)
    response.errors.push(e.message)
  }
  res.send(response);
})

const PORT = 3000;
app.listen(PORT, () => console.log(`Server running on port ${PORT}!`));