chore: add dnsutils

.github/workflows/release.yml

@@ -90,7 +90,6 @@ jobs:
     needs: push-images
     uses: ./.github/workflows/docker.yml
 
-  # direct use ghcr or docker-hub image?
   fly-deploy:
     name: Deploy fly app
     runs-on: ubuntu-latest

Dockerfile

@@ -69,7 +69,7 @@ FROM ${RUNNER_IMAGE} as runner
 #   apt-get install -y libstdc++6 openssl libncurses5 locales ca-certificates \
 #   && apt-get clean && rm -f /var/lib/apt/lists/*_*
 RUN apt-get update -y && \
-  apt-get install -y locales curl iputils-ping \
+  apt-get install -y locales curl iputils-ping dnsutils\
   && apt-get clean && rm -f /var/lib/apt/lists/*_*
 
 RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && locale-gen

Taskfile-fly-io.yml

@@ -16,7 +16,6 @@ tasks:
   st: fly status
   # deploy new app version
   up: fly deploy --build-arg GIT_COMMIT_ID=$(git log -1 --format="%H") --build-arg GIT_COMMIT_TIME=$(git log -1 --format="%ct")
-
   reup: fly app restart
   log: fly logs
   open: fly open

lib/hello_api.ex

@@ -16,7 +16,8 @@ defmodule HelloApi do
       build_mode: build_mode(),
       build_time: build_time(),
       system: System.build_info(),
-      commit: commit()
+      commit: commit(),
+      node: Node.self()
     }
   end
 

lib/my_plug.ex

@@ -0,0 +1,14 @@
+defmodule MyPlug do
+  import Plug.Conn
+
+  def init(options) do
+    # initialize options
+    options
+  end
+
+  def call(conn, _opts) do
+    conn
+    |> put_resp_content_type("text/plain")
+    |> send_resp(200, "Hello world")
+  end
+end

run/bandit-websocket.exs

@@ -0,0 +1,51 @@
+#!/usr/bin/env elixir
+
+Mix.install([:plug, :bandit, :websock_adapter])
+
+defmodule EchoServer do
+  def init(options) do
+    {:ok, options}
+  end
+
+  def handle_in({"ping", [opcode: :text]}, state) do
+    {:reply, :ok, {:text, "pong"}, state}
+  end
+
+  def terminate(:timeout, state) do
+    {:ok, state}
+  end
+end
+
+defmodule Router do
+  use Plug.Router
+
+  plug Plug.Logger
+  plug :match
+  plug :dispatch
+
+  get "/" do
+    send_resp(conn, 200, """
+    Use the JavaScript console to interact using websockets
+
+    sock  = new WebSocket("ws://localhost:4000/websocket")
+    sock.addEventListener("message", console.log)
+    sock.addEventListener("open", () => sock.send("ping"))
+    """)
+  end
+
+  get "/websocket" do
+    conn
+    |> WebSockAdapter.upgrade(EchoServer, [], timeout: 60_000)
+    |> halt()
+  end
+
+  match _ do
+    send_resp(conn, 404, "not found")
+  end
+end
+
+require Logger
+webserver = {Bandit, plug: Router, scheme: :http, port: 4000}
+{:ok, _} = Supervisor.start_link([webserver], strategy: :one_for_one)
+Logger.info("Plug now running on http://localhost:4000")
+Process.sleep(:infinity)

run/observer.sh

@@ -0,0 +1,68 @@
+#!/bin/bash
+
+# After opening a Wireguard connection to your Fly network, run this script to
+# open a BEAM Observer from your local machine to the remote server. This creates
+# a local node that is clustered to a machine running on Fly.
+
+# In order for it to work:
+# - Your wireguard connection must be up.
+# - The COOKIE value must be the same as the cookie value used for your project.
+# - Observer needs to be working in your local environment. That requires WxWidget support in your Erlang install.
+
+# When done, close Observer. It leaves you with an open IEx shell that is connected to the remote server. You can safely CTRL+C, CTRL+C to exit it.
+
+# COOKIE NOTE:
+# ============
+# You can explicitly set the COOKIE value in the script if you prefer. That would look like this.
+#
+# COOKIE=YOUR-COOKIE-VALUE
+
+set -e
+
+if [ -z "$COOKIE" ]; then
+    echo "Set the COOKIE your project uses in the COOKIE ENV value before running this script."
+    exit 1
+fi
+
+if ! command -v jq &> /dev/null; then
+    echo "jq is not installed. Please install it before running this script. It is a command-line JSON processor."
+    exit 1
+fi
+
+# Get the data we need in JSON format
+json_data=$(fly status --json)
+
+# Extract app name
+app_name=$(echo "$json_data" | jq -r '.Name')
+
+# Extract private_ip for the first started machine
+private_ip=$(echo "$json_data" | jq -r '.Machines[] | select(.state == "started") | .private_ip' | head -n 1)
+
+# Extract image_ref tag hash for the first started machine
+image_tags=$(echo "$json_data" | jq -r '.Machines[] | select(.state == "started") | .image_ref.tag | sub("deployment-"; "")' | head -n 1)
+
+if [ -z "$private_ip" ]; then
+    echo "No instances appear to be running at this time."
+    exit 1
+fi
+
+# Assemble the full node name
+FULL_NODE_NAME="${app_name}-${image_tags}@${private_ip}"
+echo Attempting to connect to $FULL_NODE_NAME
+
+# IMPORTANT:
+# ==========
+# Fly.io uses an IPv6 network internally for private IPs. The BEAM needs IPv6
+# support to be enabled explicitly.
+#
+# The issue is, if it's enabled globally like in a `.bashrc` file, then setting
+# it here essentially flips it OFF. If not set globally, then it should be set
+# here. Choose the version that fits your situation.
+#
+# It's the `--erl "-proto_dist inet6_tcp"` portion.
+
+# Toggles on IPv6 support for the local node being started.
+iex --erl "-proto_dist inet6_tcp" --sname my_remote --cookie ${COOKIE} -e "IO.inspect(Node.connect(:'${FULL_NODE_NAME}'), label: \"Node Connected?\"); IO.inspect(Node.list(), label: \"Connected Nodes\"); :observer.start"
+
+# Does NOT toggle on IPv6 support, assuming it is enabled some other way.
+# iex --sname my_remote --cookie ${COOKIE} -e "IO.inspect(Node.connect(:'${FULL_NODE_NAME}'), label: \"Node Connected?\"); IO.inspect(Node.list(), label: \"Connected Nodes\"); :observer.start"

run/plug-cowboy.exs

@@ -0,0 +1,24 @@
+#!/usr/bin/env elixir
+
+Mix.install([:plug, :plug_cowboy])
+
+defmodule MyPlug do
+  import Plug.Conn
+
+  def init(options) do
+    # initialize options
+    options
+  end
+
+  def call(conn, _opts) do
+    conn
+    |> put_resp_content_type("text/plain")
+    |> send_resp(200, "Hello world")
+  end
+end
+
+require Logger
+webserver = {Plug.Cowboy, plug: MyPlug, scheme: :http, options: [port: 4000]}
+{:ok, _} = Supervisor.start_link([webserver], strategy: :one_for_one)
+Logger.info("Plug now running on localhost:4000")
+Process.sleep(:infinity)

test/my_plug_test.exs

@@ -0,0 +1,19 @@
+defmodule MyPlugTest do
+  use ExUnit.Case, async: true
+  use Plug.Test
+
+  @opts MyPlug.init([])
+
+  test "returns hello world" do
+    # Create a test connection
+    conn = conn(:get, "/hello")
+
+    # Invoke the plug
+    conn = MyPlug.call(conn, @opts)
+
+    # Assert the response and status
+    assert conn.state == :sent
+    assert conn.status == 200
+    assert conn.resp_body == "Hello world"
+  end
+end