Myujth

My code was running fine but this happened when I ran it today:

(node:8592) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 3): MongoParseError: Invalid connection string

Here is a snippet of app.js:

var express = require("express"),
app = express(),
bodyParser = require("body-parser"),
mongoose = require("mongoose"),
passport = require("passport"),
localStrategy = require("passport-local"),
methodOverride = require("method-override"),
flash = require("connect-flash"),
session = require("express-session"),
campground = require("./models/campground"),
comment = require("./models/comments"), //name of the model is comment
User = require("./models/user"),
seedDB = require("./seeds");

var campgroundRoutes = require("./routers/campground"),
commentRoutes = require("./routers/comment"),
authRoutes = require("./routers/auth");

var url = process.env.DATABASE_URL || "mongodb://localhost:27017/yelp_camp"; 
mongoose.connect(url, useNewUrlParser: true );
mongoose.set("useFindAndModify", false);
mongoose.set("useCreateIndex", true);

What am I missing in my code?

It's always a good practice to handle the promise returned.

var url = process.env.DATABASE_URL || "mongodb://localhost:27017/yelp_camp"; 
mongoose.connect(url, useNewUrlParser: true )
 .then(() => console.log("Connection Successful"))
 .catch(err => console.log(err));

So this will avoid the UnhandledPromiseRejectionWarning and also you will know the reason why the connection failed. Most probably the issue is with URL.