For due date: see the jpa03 entry on Canvas: https://ucsb.instructure.com/courses/21167/assignments/262241

Instructions for jpa03

If you run into problems, let us know on the #help-jpa03 channel on the slack.

This is an individual lab on the topic of deploying Java web apps that use OAuth and Databases, using Dokku.

You may cooperate with one or more pair partners from your team to help in debugging and understanding the lab, but each person should complete the lab separately for themselves.

Goal

By the end of this lab, you’ll have deployed your own copy of the starter code repo (https://github.com/ucsb-cs156-f24/STARTER-jpa03) on both localhost and Dokku.

This app is a full-stack web app with:

• A front-end built in React (under the directory ./frontend)
• A back-end built in Spring Boot (the code for this is under the directory ./src, plus the pom.xml at the top level
• OAuth integration; this allows the app to have a “login/logout” feature based on Google Accounts (e.g. your UCSB Google Account)
• A SQL database, which runs using H2 (an in-memory database) on localhost, and using Postgres when running on Dokku.
• Automatic generation of javadoc and Storybook/Chromatic web pages for both the production code (main branch) and all branches that have open pull requests targetting the main branch.

This app is not intended as a coherent app to solve a real-world problem, but as a code base that demonstrates many of the techniques you would need in such an app. The legacy code apps that we’ll work with in this course have a similar structure.

Here is an example of this app, up and running. Try logging in with your UCSB Google Credentials:

• https://jpa03-staff.dokku-00.cs.ucsb.edu/

If the menu looks like this, click on the hamburger icon (☰) to expose the Login button:

It should then look like this, and you should be able to login:

Once you are logged in, you’ll see a navigation bar like this one (though you will not see the Admin menu):

None of the menus will do much of anything. It turns out that the application is a shell of an application that:

• allows users to login and logout using a Google account
• allows the developer to configure some users as “admins”
• allows admin users to see who has logged in to the app in the past (by storing each login in a database)

However, we need those basic functions as a basis to build more complex functions, and every student in the class needs to know how to configure and deploy an app on Dokku. The configuration has several parts:

• Setting up SSL (https) for your dokku app
• Configuring Google OAuth (this can be tested on localhost first)
• Setting up the dokku app
• Connecting it to a Github repo
• Configuring https
• Configuring a postgres database on Dokku

So, let’s get started.

Step 1: Understanding what we are trying to do

What are we trying to accomplish in this lab?

This lab has little to no programming. The point of the lab is to walk you through the steps you need to take to deploy full-stack Spring Boot/React apps on Dokku, configuring them for Google OAuth (for logins) and a Postgres database.

There are quite a few configuration steps that are needed, and we want to get you used to those before we start introducing the coding challenges as well.

Step 2: Create your repo

There should already be a repo for you under the course organization with a name in this format:

• https://github.com/ucsb-cs156-f24/jpa03-githubid

where github is your github id.

If not, create one for yourself following that naming convention; it should initially be public, and empty (no README, license or .gitignore.)

Clone that repo somewhere and cd into it.

Click the triangle if you need a reminder on how to clone a repo

As in previous labs, you should have a directory somewhere, perhaps ~/cs156 in which you clone the repos you work on in this course.

cd into that directory, then use git clone followed by the url for your repo, e.g.

cd ~/cs156
git clone git@github.com:ucsb-cs156-f24/jpa03-yourGithubid.git
cd jpa03-yourGithubid

Then add this remote:

git remote add starter https://github.com/ucsb-cs156-f24/STARTER-jpa03

That sets up starter as a remote with the code from this github repo:

• https://github.com/ucsb-cs156-f24/STARTER-jpa03

Then do:

git checkout -b main
git pull starter main
git push origin main

Step 3: Configure Actions and Github Pages

In this step, we’ll:

• Set up Chromatic Project Token
• Enable Github Actions if not already enabled
• Set up Github Pages
• Check that Storybook/Chromatic are building properly

Step 3.1: Enable Chromatic

In this step, we are setting up Storybook, which is software that allows us to document and test the frontend of our application, one component at a time, without needing the backend at all.

As an example of Storybook, here is a link to the storybook for the starter code:

• https://6709627038191f269c9a870b-waqkeiwvio.chromatic.com/

Click the triangle to read more about why Storybook and Chromatic are useful when building a full-stack web applications.

Storybook is helpful for several reasons:

• You can develop frontend components without depending on whether the backend part is working yet. This is very helpful for team projects where you may want to have different team members working on the frontend and the backend. (Note, however, that it’s very important to agree in advance on the interface between the frontend and the backend!).
• You can test the frontend components separately from the backend. This is very helpful when debugging problems in the web app which are typically caused by one of three things (a) a problem in the backend, (b) a problem in the frontend (c) a error in communication between the front and backend. Having a way to isolate the frontend makes it much easier to identify the root causes of such problems.
• It serves as a way of documenting the collection of user interface elements that a present in the code base. This is helpful for being able to reuse user interface components, or identify the existing part of the user interface that’s closest to the one you intend to build.
• It helps to be able to identify opportunities for refactoring the user interface code to make it more consistent.

Chromatic.com, in addition to providing web hosting for Storybook sites, offers:

“… a visual testing & review tool that scans every possible UI state across browsers to catch visual and functional bugs. Assign reviewers and resolve discussions to streamline team sign-off.”

The idea is that the first time your Storybook is built, it takes a screenshot of each user element. On subsequent builds, it again takes those screenshots, and if/when any of them change, it asks whether the change should be approved or rejected. This is incorporated into the Github Action for Storybook which will remain marked with a yellow (i.e. unfinished, incomplete) until the developer reviews the changes in the user interface elements.

To configure your web app for Chromatic, you need to:

• Create a Chromatic.com account (using your Github login)
• Visit the page https://ucsb-cs156.github.io/topics/chromatic and follow the instructions to set up your repo as a Chromatic project.
• Once it is setup as a project, you’ll be able to obtain a value for the CHROMATIC_PROJECT_TOKEN
• Then, you can set up the CHROMATIC_PROJECT_TOKEN as a repository level secret, accessible to the Github Actions scripts.

Step 3.2: Enable Github Actions (if not already enabled)

Go to the webpage for your repo on Github. Find the Actions tab on your repo. It should look like one of the images below

If GitHub Actions are not yet enabled:	If GitHub Actions are already enabled:

If it looks like the one on the left, click the green button that says “Enable Actions on this Repository”.

Step 3.3: Enable Github Pages

Next, visit the file docs/github-pages.md on GitHub or in your repo and read what it says to do to configure the documentation for your repo on Github Pages.

When you’ve completed this step, on your main repo page on Github, the link at right under About should take you to the Github Pages for your repo; it should look like this:

The link will be of the form: https://ucsb-cs156-f24.github.io/jpa03-yourGithubId, where yourGithubId is replaced by your Github Id. Click on the link, and you should see a page like this one:

If you don’t:

• Look through the instructions again
• Try manually running the Github Action /02-gh-pages-rebuild-part-1.yml (note that it will automatically start 04-gh-pages-rebuild-part-2.yml when it is finished.
• If any steps in workflows 02 or 04 completed with errors, try running them again. It is not unusual for the “Deploy” step to fail; there are sometimes race conditions with multiple jobs trying to publish to the site at the same time, and we have not yet determined a way to prevent that (see the box below for instructions on how to re-run a failed Github Action).
• If the jobs fail repeatedly or on a step other than the “Deploy” step, you may need to ask the staff for help.

Click the triangle to read about how to re-run failed Github Actions

Here’s how to re-run failed Github Actions:

1. Go to the Github Actions tab of your repo

2. On the left side, in the list of workflows, if the one you are looking for is not listed, click Show More Workflows, as shown here:

   

3. On a failed workflow, if you click it, there should be a button like this to re-run the failed workflow:

   

   Alternatively, find the button upper left that says “Run Workflow”, click it, and then click the green Run Workflow button, as shown here:

   

Step 3.4: Check that Chromatic is building properly

Go to the Github Actions page for your repo and run the job 53-chromatic-main-branch.yml again; it may have failed on the first run for lack of a value for CHROMATIC_PROJECT_TOKEN.

When you’ve re-run the Github Action 53-chromatic-main-branch.yml, navigate to the Github Pages site for repo.

And the links for Storybook and build info should take you to pages that looks like these:

storybook	build info

Step 4: Configure your app for localhost as documented in the README.md

Before we start configuring your app, let’s take just a moment to learn what OAuth is.

About OAuth

OAuth is a protocol that allows you to delegate the login/logout functionality (user authentication) to a third party such as Google, Facebook, GitHub, Twitter, etc. If you’ve ever used a website that allows you to “Login with Google”, “Login With Facebook”, or “Login with Github” then chances are good that app was built using OAuth.

Indeed, you’ve already encountered an examples of GitHub OAuth earlier in the course when you used your GitHub account to log into the https://ucsb-cs-github-linker.herokuapp.com

When implementing a website that can store information and making it available on the public internet it’s important to secure the site; otherwise, bad actors may fill your database with unsavory material.

One choice is to implement our own username/password authentication, but I want to strongly caution you: if you take on the responsibility of storing passwords, you are assuming a lot of risk. The problem is that people reuse passwords, so even if you think that your site isn’t that important, the problem is that the passwords you are storing might be the same ones folks are using for other sensitive apps.

Using OAuth sidesteps this issue:

• Your app never actually sees the password the user enters; it is entered on a page that is hosted by Google (or Facebook, or Github, or whoever is providing the OAuth service.)
• The user doesn’t need to come up with a new username or password; they can use one they already have.

Implementing OAuth can be tricky at first, but once you get the hang of it, it’s far easier than everything you would need to do to really work with usernames/passwords securely and safely.

Steps to Configure your app

The next step is to read through the README.md and configure your app as indicated there.

As shown in the README.md, these steps include the following. Each of these is documented in files linked to from the README.md file so we won’t repeat those here; we’ll just link to them.

1. Configuring GitHub Pages for the documentation
2. Getting Started on localhost, which includes:
   • Setting up Google OAuth credentials
   • Entering those credential in the .env file
   • Learning how to run the backend and frontend in separate windows

The .env file should not be committed to GitHub

I already made this point, but I really, really want to emphasize it.

One of the values in the .env file is called a client secret for a reason.

If it leaks, it can be used for nefarious purposes to compromise the security of your account; so don’t let it leak!

Never, ever, commit those to GitHub, and try to only share them in DMs on Slack (not in public channels).

Security starts with making smart choices about how to handle credentials and tokens. The stakes get higher when you start being trusted with credentials and tokens at an employer, so learning how to handle these with care now is a part of developing good developer habits.

The staff reserve the right to deduct points if we find that you have committed your .env file to GitHub.

Green check ✅, not red X ❌

Once you’ve completed your setup, GitHub Actions should be running on the main branch with a green check, not a red X. If there are problems there, address those as best you can before submitting.

Explaning the H2-Console and Swagger links.

You may have noticed two extra links on your localhost version of the app:

• H2-Console is a link that is typically only available when running on localhost. It provides access to database features for the database that is used when we run on localhost, which uses software called H2. This link can be used to bring up H2 and look directly into the database tables that are present in the application.
• Swagger is a link that takes you to a special page that is automatically generated from the backend controller code. This page allows you to interact directly with backend api endpoint, endpoints that often (though not always) take inputs, and typically (though not always) return their responses in JSON format.

You are encourged to take a look at each of these. We’ll be using them extensively later in the course.

Note that when we run our application on Dokku, we typically do not use H2, but a different database called Postgres, so we don’t use the H2-Console there; it’s typically only for when we are running on localhost. We will, however, sometimes enable swagger access when running on dokku. We’ll discuss this more at a later step in the lab.

Step 5: Configure your app to run on Dokku

The steps to get your app up and running on Dokku are documented here:

• https://ucsb-cs156.github.io/topics/dokku/deploying_an_app.html

Note that there are are more steps than in the previous labs, since this app is more complex:

• It requires configuration variables
• It requires a Postgres database
• It requires a special dokku git setting (to keep the .git directory)

Once you’ve followed these instructions, try logging in to your app. It should be available at this url:

https://jpa03-yourGithubId.dokku-xx.cs.ucsb.edu

Where:

• yourGithubId is your Github Id
• yourGithubId is your two-digit team/dokku number

You should test the following features:

• You should see be able to login with your UCSB Google account
• You should see an Admin menu, where you can see the names of everyone that has logged in

What if it doesn’t work?

If it doesn’t work:

• Check on the Slack channel #help- to see if there are any known issues.
• Ask folks on your own team for help first on your team’s slack channel.
• Post a specific question on the #help- slack channel—note what you were trying to do, what you expected, and what happened instead. Screenshots or copy/pasted console output is helpful!
• Come to office hours (posted here: <>)
• Ask during class on #help-lecture-discussion

Step 6: Enable Link to Swagger

For a production dokku deployment of a real, user-facing app, we would normally not want a link to the Swagger tool to appear. This is not functionality that a normal end user would be interacting with.

However, for developers, it is often convenient to enable this link on deployments of our app that are being used for quality assurance (QA), demos, etc.

You can enable this link by setting the following configuration variable on dokku:

dokku config:set appname SHOW_SWAGGER_UI_LINK=true

Where appname in this case is jpa03-yourGithubId.

Type that command, and when it finishes, you should be able to refresh the web page for your dokku deployment of the app and see the Swagger link in the menu bar.

Step 7: Add link to running app to your README.md file

At the top of your README.md, you’ll find this:

Follow these instructions; i.e. put in the link to your running app on Dokku, and remove the comment so that afterwards it looks something like this (but with your actual Dokku link, not the example value shown here).

Step 8: Submit on Canvas

Before submitting on Canvas, check all of the items in the grading rubric below; make sure you are in compliance with all of them.

If so, then you are ready to submit on Canvas.

Remember to submit a link to your repo, not a link to your running app.

Grading Rubric:

• (10 pts) README in your repo has a link to your running web app.
• (10 pts) There is a running web app at https://-githubid.dokku-xx.cs.ucsb.edu
• (10 pts) Running web app has the ability to login with OAuth through a Google Account.
• (10 pts) The ADMIN_EMAILS variable is set to include all staff emails (see list below) plus your own email.
  • The correct setting is shown below, except with your email in place of youremail
  • ADMIN_EMAILS=youremail@ucsb.edu,phtcon@ucsb.edu,sangitakunapuli@ucsb.edu,amey@ucsb.edu,jenilrajeshkumar@ucsb.edu,djensen@ucsb.edu,gracefeng@ucsb.edu,hongrui_su@ucsb.edu
• (10 pts) The link on your main repo page is set your Github Pages page (i.e. https://ucsb-cs156-f24.github.io/-yourGithubId, where yourGithubId is replaced by your Github Id. )
• (10 pts) The Github Pages page shows a web page that looks like the example in the lab instructions and has the correct content.
• (10 pts) Chromatic is configured correctly, and the Github Pages site has a Storybook configured properly.
• (10 pts) GitHub Actions runs correctly and there is a green check (not a red X) on your main branch
• (10 pts) On dokku, the Swagger link appears in the menu bar.
• (10 pts) There is a post on Canvas for this assignment that has the correct content (i.e. a link to the repo, not the running app on Dokku)

Note that the Rubric above is subject to change, but if it does:

• You’ll be notified during a class meeting
• You’ll have an additional week from the date of the announced change to get your repo in shape with the new requirements.

Instructor Resources

Click the triangle for a list of tasks the instructor should do prior releasing this lab.

• Create repos using the https://ucsb-cs-github-linker.herokuapp.com
• Set up starter code in the course organization, and update links
• Create a Canvas assignment for

• Make sure the app https://jpa03-staff.dokku-00.cs.ucsb.edu/ is up and running, and is sync’d with the starter code:

  i.e, on dokku-00 for example, do:

  dokku git:sync jpa03-staff https://github.com/ucsb-cs156-f24/STARTER-jpa03 main
  dokku ps:rebuild jpa03-staff
  

• Remove older users from the database, e.g.

  dokku postgres:connect jpa03-staff-db
  select * from users;
  delete from users where id>2;
  \q
  

• Proofread the instructions in this file, and request that the staff (TAs/LAs do also)
• Consider assigning at least one TA/LA (preferably the one with the least prior experience with the course) to complete the lab in it’s entirety to debug the starter code and instructions

• Be sure that the organization settings are set like this, in, for example, https://github.com/organizations/ucsb-cs156-s24/settings/actions

  This is needed so that the github actions scripts have write access to the directory.

  

  This setting is probabaly also a good idea: