index.js

const { createCodeFile } = require("./createCodeFile"),
  { removeCodeFile } = require("./removeCodeFile"),
  {
    executeJava,
    executePython,
    executeCorCPP,
    executeJavaScript,
    executeGo,
    executeCsharp,
  } = require("./executeCode");

const express = require("express");
const bodyParser = require("body-parser");
const app = express();
const port = process.env.PORT || 3000;
var cors = require("cors"); //use this

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(cors());

// Total languages supported
const supportedLanguages = ["java", "cpp", "py", "c", "js", "go", "cs"];
const compilerVersions = [
  "11.0.15",
  "11.2.0",
  "3.7.7",
  "11.2.0",
  "16.13.2",
  "1.18.3",
  "6.12.0.140",
];

app.post("/", async (req, res) => {
  let output = "";
  const { language = "java", code, input = "" } = req.body;

  if (code === undefined || code.trim() === "")
    output = "No code specified to execute.";
  if (!supportedLanguages.includes(language))
    output = `Language ${language} is not supported. Please refer to docs to know the supported languages.`;

  if (output === "") {
    const codeFile = createCodeFile(language, code);

    console.log(codeFile, code, input);

    switch (language) {
      case "java":
        output = await executeJava(codeFile, input);
        break;
      case "py":
        output = await executePython(codeFile, input);
        break;
      case "cpp":
        output = await executeCorCPP(codeFile, input);
        break;
      case "c":
        output = await executeCorCPP(codeFile, input);
        break;
      case "js":
        output = await executeJavaScript(codeFile, input);
        break;
      case "go":
        output = await executeGo(codeFile, input);
        break;
      case "cs":
        output = await executeCsharp(codeFile, input);
        break;
    }

    removeCodeFile(codeFile.split(".")[0], language);
  }

  res.send(output);
});

app.get("/list", (req, res) => {
  let versionObj = [];
  for (let i = 0; i < supportedLanguages.length; i++) {
    versionObj.push({
      language: supportedLanguages[i],
      compilerVersion: compilerVersions[i],
    });
  }
  res.send(versionObj);
});

app.listen(port);