Using WRAP ASYNC

AN ASYNC FUNCTION IS CREATED.WHICH WRAPS THE ASYNC CALLBACK.

function asyncWrap(fn) {
  return function (req, res, next) {
    fn(req, res, next).catch((err) => next(err));
  };

} 

WE WRAP EVERY TRY-CATCH TO ASYNC WRAP.


// INDEX ROUTE
app.get(
  "/chats",
  asyncWrap(async (req, res, next) => {
    let chats = await Chat.find();
    res.render("index.ejs", { chats });
  })
);

// NEW ROUTE
app.get("/chats/new", (req, res) => {
  res.render("new.ejs");
});

const ExpressError = require("./ExpressError.js");
// HANDLING ASYNC ERROR MESSAGES
app.use((err, req, res, next) => {
  let { status = 500, message = " UNKNOWN ERROR OCCURRED" } = err;
  res.status(status).send(message);
});

// SHOW ROUTE
app.get(
  "/chats/:id",
  asyncWrap(async (req, res, next) => {
    let { id } = req.params;
    let chat = await Chat.findById(id);
    if (!chat) {
      next(new ExpressError(404, "chat not found"));
    }

    res.render("edit.ejs", { chat });
  })
);
// POST ROUTE
app.post(
  "/chats",
  asyncWrap(async (req, res, next) => {
    let { from, to, msg } = req.body;
    let newchat = new Chat({
      from: from,
      msg: msg,
      to: to,
      created_at: new Date(),
    });
    await newchat.save();

    res.redirect("/chats");
  })
);

// EDIT ROUTE
app.get(
  "/chats/:id/edit",
  asyncWrap(async (req, res, next) => {
    let { id } = req.params;

    let chat = await Chat.findById(id);
    res.render("edit.ejs", { chat });
  })
);
let chat1 = new Chat({
  from: "abhi",
  to: "ash",
  msg: "silencer",
  created_at: new Date(),
});

//UPDATE ROUTE
app.put(
  "/chats/:id",
  asyncWrap(async (req, res, next) => {
    let { id } = req.params;
    let { msg: newMsg } = req.body;
    let updatedmsg = await Chat.findByIdAndUpdate(
      id,
      { msg: newMsg },
      { new: true, runValidators: true }
    );
    console.log(updatedmsg);
    res.redirect("/chats");
  })
);

// DELETE ROUTE
app.delete(
  "/chats/:id",
  asyncWrap(async (req, res, next) => {
    let { id } = req.params;
    let deletedChat = await Chat.findByIdAndDelete(id);
    console.log(deletedChat);
    res.redirect("/chats");
  })
);




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