timdavidson2 / herokureadme

Deploying a Node Web Server to Heroku

This guide walks through the necessary steps to deploy your full stack Node.js application to Heroku!

Prerequisites

To begin with, you'll need a git repository initialized locally with your basic web server code working and committed.

There are a couple of ways to do this:

• If you cloned from a remote repository and then wrote/committed your code to the local clone, you should be set and can go straight to deploying.

• If you haven't set up a git repository for your files yet (or didn't clone), proceed with the following steps:

1. Run git init locally in the folder with your web server files.

   • If you want to also push to GitHub in addition to hosting on Heroku (recommended), you can follow the Adding Existing Projects to GitHub through the command line Guide

2. Commit all changes (if you haven't already with the above steps).

3. You may also want to create a .gitignore file if you don't have one already.

   • This file will allow you to tell git to not track certain files.

   • Inside of the .gitignore file, add node_modules/ as the first line and save the file. Now, git should no longer track node_modules files.

   • You can consult the GitHub gitignore Documentation or this node gitignore example for more information on how to do this.

If you haven't run into any errors at this point, you should be able to proceed to the next section.

Steps to Deploy

1. Log in to Heroku.

   • If you are a Windows user, open the Command Prompt (cmd.exe NOT Git Bash) and type heroku login in the command line. Enter your Heroku credentials. Keep this Command Prompt open in the background. Then, open Git Bash and navigate to the folder with your code.

   • If you are a Mac user, open the Terminal and type heroku login in the command line. Enter your Heroku credentials. Navigate to the folder with your code.

2. Run the command: git remote –v.

   • This is to show you that right now, you do not have heroku listed as a remote repository.

3. Run the command heroku create.

   • This will create an app instance on the Heroku server and will add heroku as a remote for your local git repository.

4. Run git remote –v again.

   • This isn't necessary, but helps to confirm that Heroku is now in your list of remotes. This time you should see the heroku remote.

5. Ensure that your package.json file is set up correctly. It must have a start script and all the project's dependencies defined. E.g.:

   {
     "name": "starwars",
     "version": "1.0.0",
     "description": "Helps you find the characters you are looking for",
     "main": "server.js",
     "dependencies": {
        "express": "^4.16.3"
     },
     "scripts": {
       "start": "node server.js"
     }
   }

6. Ensure your web server is starting with a dynamic port.

   • For an express app, the code for this would look like:

   var PORT = process.env.PORT || 3001;
   ...
   app.listen(PORT, function() {

   • This allows you to get the port from the bound environment variable (using process.env.PORT) if it exists, so that when your app starts on heroku's machine it will start listening on the appropriate port.

   • You app will still run on port 3001 locally if you haven't set an environment variable.

7. Ensure that you have at least one HTML page being served at the "/" route. Example:

   app.get("/", function(req, res) {
     res.json(path.join(__dirname, "public/index.html"));
   });

8. Make sure that the application actually works locally. If it doesn't work locally, it won't deploy.

9. Commit any changes you've made up until this point.

10. Run the command git push heroku main. A series of processes will be initiated. Once the process is complete, note the name of the app.

11. Log in to your Heroku account. You will see all of your hosted web applications. Click on the app that has the same name as the app you just created.

12. Click on settings. Then, scroll down until you see "Domains". Note the URL listed under Heroku Domain.

13. Navigate to that URL in your browser. If all went well, you should see your web application live online!

Troubleshooting

• If your Heroku app fails to deploy, run the command heroku logs in your command line

  • This should print all the logs produced by both Heroku and your application before the deployment failed.

  • Look for the first indication of an error in the logs. If the error message isn't clear, search on Google or ask the Instructional Staff for help.