Deploying Phoenix on Hop3¶

defmodule MyappWeb.HealthController do
  use MyappWeb, :controller

  def up(conn, _params) do
    text(conn, "OK")
  end

  def health(conn, _params) do
    json(conn, %{
      status: "ok",
      timestamp: DateTime.utc_now() |> DateTime.to_iso8601(),
      uptime: :erlang.statistics(:wall_clock) |> elem(0) |> div(1000),
      memory: %{
        total: :erlang.memory(:total) |> div(1024 * 1024),
        processes: :erlang.memory(:processes) |> div(1024 * 1024)
      }
    })
  end

  def info(conn, _params) do
    json(conn, %{
      name: "hop3-tuto-phoenix",
      version: "1.0.0",
      elixir_version: System.version(),
      otp_version: :erlang.system_info(:otp_release) |> to_string()
    })
  end
end

defmodule MyappWeb.Router do
  use MyappWeb, :router

  pipeline :browser do
    plug :accepts, ["html"]
    plug :fetch_session
    plug :fetch_live_flash
    plug :put_root_layout, html: {MyappWeb.Layouts, :root}
    plug :protect_from_forgery
    plug :put_secure_browser_headers
  end

  pipeline :api do
    plug :accepts, ["json"]
  end

  scope "/", MyappWeb do
    pipe_through :browser

    get "/", PageController, :home
  end

  # Health check endpoints (no CSRF protection)
  scope "/", MyappWeb do
    pipe_through :api

    get "/up", HealthController, :up
    get "/health", HealthController, :health
    get "/api/info", HealthController, :info
  end
end

defmodule MyappWeb.PageController do
  use MyappWeb, :controller

  def home(conn, _params) do
    render(conn, :home)
  end
end

import Config

if config_env() == :prod do
  # Get configuration from environment variables
  secret_key_base =
    System.get_env("SECRET_KEY_BASE") ||
      raise """
      environment variable SECRET_KEY_BASE is missing.
      You can generate one by calling: mix phx.gen.secret
      """

  host = System.get_env("PHX_HOST") || "localhost"
  port = String.to_integer(System.get_env("PORT") || "4000")

  config :hop3-tuto-phoenix, :dns_cluster_query, System.get_env("DNS_CLUSTER_QUERY")

  config :hop3-tuto-phoenix, MyappWeb.Endpoint,
    url: [host: host, port: 443, scheme: "https"],
    http: [
      ip: {0, 0, 0, 0},
      port: port
    ],
    secret_key_base: secret_key_base

  # Configure logging
  config :logger, level: :info
end

import Config

config :hop3-tuto-phoenix, MyappWeb.Endpoint,
  cache_static_manifest: "priv/static/cache_manifest.json",
  server: true

# Do not print debug messages in production
config :logger, level: :info

# config/runtime.exs
database_url =
  System.get_env("DATABASE_URL") ||
    raise "DATABASE_URL environment variable is missing"

config :hop3-tuto-phoenix, Myapp.Repo,
  url: database_url,
  pool_size: String.to_integer(System.get_env("POOL_SIZE") || "10")

# Already included by default in Phoenix 1.7+
# Create a LiveView:
defmodule MyappWeb.CounterLive do
  use MyappWeb, :live_view

  def mount(_params, _session, socket) do
    {:ok, assign(socket, count: 0)}
  end

  def handle_event("increment", _, socket) do
    {:noreply, update(socket, :count, &(&1 + 1))}
  end

  def render(assigns) do
    ~H"""
    <div>
      <h1>Count: <%= @count %></h1>
      <button phx-click="increment">+</button>
    </div>
    """
  end
end

# config/config.exs
config :hop3-tuto-phoenix, Oban,
  repo: Myapp.Repo,
  queues: [default: 10]

# config/runtime.exs
config :libcluster,
  topologies: [
    k8s: [
      strategy: Cluster.Strategy.DNSPoll,
      config: [
        query: System.get_env("DNS_CLUSTER_QUERY"),
        node_basename: "hop3-tuto-phoenix"
      ]
    ]
  ]