Deploy

Goal

This snapshot advances Junction Almanac by teaching you to package and deploy Junction Almanac to Fly.io.

Every numbered folder is a complete Rails application. Run this stage independently, then compare it with the previous snapshot to isolate the new responsibility.

Prerequisites

Use Ruby 3.1 or newer, Bundler, PostgreSQL through Docker, and a terminal. Basic Ruby, HTML, and SQL vocabulary will make the framework conventions easier to recognize.

The app listens on port 3000. PostgreSQL is exposed on host port 5434, and every snapshot names a different database so lesson data never leaks between stages.

• Ruby and Bundler
• Docker with Compose
• A code editor and terminal

Concepts

Fly Machines run the multi-stage Docker image, route HTTPS traffic to internal port 3000, and execute database preparation as a release command.

Keep the Rails request path visible: the router selects a controller action, Active Record handles data rules, and an ERB view renders the response inside the shared layout.

Walkthrough

Review the Dockerfile and fly.toml, choose a unique app name, attach PostgreSQL or set DATABASE_URL, provide Rails secrets, and deploy.

Read the focused example, then inspect the matching repository snapshot for the surrounding configuration, validation, failure paths, and accessible markup.

fly launch --no-deploy
fly secrets set SECRET_KEY_BASE="$(bin/rails secret)"
fly deploy

Run and verify

Enter 12-Deploy, install its bundle, prepare its database when this stage uses one, and start Rails on port 3000.

Open http://localhost:3000. Keep the server log visible so you can connect each browser action to its route, SQL query, rendered view, redirect, or validation error.

git clone https://github.com/michaeldunga1/fcc-rails-blog.git
cd fcc-rails-blog/12-Deploy
docker compose -f ../docker-compose.yml up -d
bundle install
bin/rails db:prepare db:seed
bin/rails server -p 3000

Troubleshooting

A build that succeeds but will not boot usually lacks DATABASE_URL or SECRET_KEY_BASE. Use fly logs and confirm the service internal port is 3000.

If Rails reports a missing table, run bin/rails db:prepare db:seed in the current snapshot. Connection failures usually mean PostgreSQL is stopped or port 5434 is already occupied.

• Read the first exception first
• Confirm the current numbered folder
• Never commit secrets or config/master.key

Try this

Deploy, check /up, sign in from a private browser window, publish one post, and complete a password reset.

Test one successful request and one invalid or unauthorized request. A production-minded Rails app must preserve data rules even when someone bypasses the visible links and submits a direct request.

• Make one focused change
• Verify it in the browser
• Move on only after the checkpoint works