title: Deployed my app on heroku but got error: Failed to load resource: net::ERR_CONNECTION_REFUSED
body: <p><strong>My app's front-end is Reactjs and backend is Node js. I used express server and graphql-express server. I deployed my app successfully. But it starts with data is loading and then nothing shows. But if I run locally npm start then the heroku app is start working.</strong></p>
  
  <p><strong>This is the error I get it in browser</strong></p>
  
  <p><a href="https://i.stack.imgur.com/tatN6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/tatN6.png" alt="enter image description here"></a></p>
  
  <p><strong>This is my server's package json file. If i run in terminal npm run dev. It opens my react js app.</strong></p>
  
  <pre><code>    {
    "name": "backend",
    "version": "1.0.0",
    "description": "personish vol 2",
    "main": "server.js",
    "scripts": {
      "start": "node server.js",
      "server": "node server.js",
      "client": "npm start --prefix client",
      "dev": "concurrently \"npm run server\" \"npm run client\""
    },
    "author": "Alak",
    "license": "ISC",
    "dependencies": {
      "concurrently": "^5.0.2",
      "cors": "^2.8.5",
      "express": "^4.17.1",
      "express-graphql": "^0.9.0",
      "graphql": "^14.5.8",
      "pg": "^7.15.1",
      "pg-hstore": "^2.3.3",
      "sequelize": "^5.21.3"
    }
  }
  </code></pre>
  
  <p><strong>This is my react's package json</strong></p>
  
  <pre><code>{
    "name": "client",
    "version": "0.1.0",
    "private": true,
    "engines": {
      "node": "13.3.0",
      "npm": "6.13.0"
    },
    "dependencies": {
      "@testing-library/jest-dom": "^4.2.4",
      "@testing-library/react": "^9.3.2",
      "@testing-library/user-event": "^7.1.2",
      "apollo-boost": "^0.4.7",
      "axios": "^0.19.0",
      "firebase": "^7.6.1",
      "graphql": "^14.5.8",
      "pg": "^7.15.1",
      "react": "^16.12.0",
      "react-apollo": "^3.1.3",
      "react-dom": "^16.12.0",
      "react-dropzone": "^10.2.1",
      "react-redux": "^7.1.3",
      "react-redux-firebase": "^3.0.5",
      "react-router-dom": "^5.1.2",
      "react-scripts": "3.3.0",
      "redux": "^4.0.4",
      "redux-firestore": "^0.11.0",
      "redux-thunk": "^2.3.0"
    },
    "scripts": {
      "start": "react-scripts start",
      "build": "react-scripts build",
      "test": "react-scripts test",
      "eject": "react-scripts eject"
    },
    "eslintConfig": {
      "extends": "react-app"
    },
    "browserslist": {
      "production": [
        "&gt;0.2%",
        "not dead",
        "not op_mini all"
      ],
      "development": [
        "last 1 chrome version",
        "last 1 firefox version",
        "last 1 safari version"
      ]
    }
  }
  </code></pre>
  
  <p><strong>This is my express and graphql-express server.</strong></p>
  
  <pre><code>const express = require("express");
  const app = express();
  
  const graphqlHTTP = require("express-graphql");
  const schema = require("./schema");
  const cors = require("cors"); 
  const path = require("path");
  
  app.use(cors());
  
  app.use(
    "/graphql",
    graphqlHTTP({
      schema,
      pretty: true,
      graphiql: true
    })
  );
  app.use(express.static(path.join(__dirname, "build")));
  
  app.get("/*", (req, res) =&gt; {
    res.sendFile(path.join(__dirname, "build", "index.html"));
  });
  
  const port = process.env.PORT || 8081;
  app.listen(port, () =&gt;
    console.log(`✅  Example app listening on port ${port}!`)
  );
  </code></pre>
  
  <p><strong>This is my react's app file. Where I use Apollo boost to connect with react app and node js app. I think the error comes from here, dont know how to fix it</strong></p>
  
  <pre><code>import React from "react";
  import { ApolloClient, HttpLink, InMemoryCache } from "apollo-boost";
  import { ApolloProvider } from "react-apollo";
  const client = new ApolloClient({
    link: new HttpLink({
      uri: "http://localhost:8081/graphql"
    }),
    cache: new InMemoryCache()
  });
  </code></pre>
  
  <p><strong>This is my heroku app</strong></p>
  
  <p><a href="https://databaseapp2020.herokuapp.com/" rel="nofollow noreferrer">https://databaseapp2020.herokuapp.com/</a></p>