From 8deb142ebc15873c3a8c6853ad215882e0ed6cf9 Mon Sep 17 00:00:00 2001
From: Daniel Flanagan <daniel@lyte.dev>
Date: Thu, 17 Dec 2020 15:23:16 -0600
Subject: [PATCH] Startup-time configuration

---
 mix.exs             | 15 +++++++++++++++
 readme.md           | 13 +++++++++++++
 src/config.exs      |  3 ++-
 src/rel/env.sh.eex  | 18 ++++++++++++++++++
 src/rel/vm.args.eex | 11 +++++++++++
 src/release.exs     |  4 ++++
 6 files changed, 63 insertions(+), 1 deletion(-)
 create mode 100644 src/rel/env.sh.eex
 create mode 100644 src/rel/vm.args.eex
 create mode 100644 src/release.exs

diff --git a/mix.exs b/mix.exs
index 16727b9..c93de77 100644
--- a/mix.exs
+++ b/mix.exs
@@ -29,10 +29,25 @@ defmodule Lytedev.MixProject do
     deps_path: @deps_path,
     deps: deps(),
     docs: docs(),
+    releases: releases(),
   ]
 
   def application, do: [
     mod: {Lytedev.Application, []},
     extra_applications: [:logger],
   ]
+
+  def releases, do: [
+    lytedev: [
+      include_executables_for: [:unix],
+      applications: [runtime_tools: :permanent],
+      strip_beams: true,
+      path: Path.join(@build_path, "rel"),
+      include_erts: true,
+      rel_templates_path: Path.join(@src_path, "rel"),
+      # overlays: ["src/static"],
+      steps: [:assemble],
+      runtime_config_path: Path.join(@src_path, "release.exs"),
+    ],
+  ]
 end
diff --git a/readme.md b/readme.md
index fe33dc7..67891b2 100644
--- a/readme.md
+++ b/readme.md
@@ -13,3 +13,16 @@ iex -S mix
 ```bash
 mix test
 ```
+
+## Generate Release
+
+```bash
+MIX_ENV=prod mix release
+```
+
+## Deploy
+
+```bash
+rsync -r ./build/rel/ $YOUR_HOST:~/my-app
+ssh $YOUR_HOST ~/my-app/bin/lytedev daemon
+```
diff --git a/src/config.exs b/src/config.exs
index 951e5cc..94bb01b 100644
--- a/src/config.exs
+++ b/src/config.exs
@@ -1,6 +1,7 @@
 use Mix.Config
 
-config :lytedev, Lytedev.HttpServer, port: 3000
+{port, ""} = Integer.parse(System.get_env("PORT", "3000"))
+config :lytedev, Lytedev.HttpServer, port: port
 
 config :logger, level: :debug
 
diff --git a/src/rel/env.sh.eex b/src/rel/env.sh.eex
new file mode 100644
index 0000000..382cd83
--- /dev/null
+++ b/src/rel/env.sh.eex
@@ -0,0 +1,18 @@
+#!/bin/sh
+
+# Sets and enables heart (recommended only in daemon mode)
+# case $RELEASE_COMMAND in
+#   daemon*)
+#     HEART_COMMAND="$RELEASE_ROOT/bin/$RELEASE_NAME $RELEASE_COMMAND"
+#     export HEART_COMMAND
+#     export ELIXIR_ERL_OPTIONS="-heart"
+#     ;;
+#   *)
+#     ;;
+# esac
+
+# Set the release to work across nodes. If using the long name format like
+# the one below (my_app@127.0.0.1), you need to also uncomment the
+# RELEASE_DISTRIBUTION variable below. Must be "sname", "name" or "none".
+# export RELEASE_DISTRIBUTION=name
+# export RELEASE_NODE=<%= @release.name %>@127.0.0.1
diff --git a/src/rel/vm.args.eex b/src/rel/vm.args.eex
new file mode 100644
index 0000000..957d983
--- /dev/null
+++ b/src/rel/vm.args.eex
@@ -0,0 +1,11 @@
+## Customize flags given to the VM: http://erlang.org/doc/man/erl.html
+## -mode/-name/-sname/-setcookie are configured via env vars, do not set them here
+
+## Number of dirty schedulers doing IO work (file, sockets, and others)
+##+SDio 5
+
+## Increase number of concurrent ports/sockets
+##+Q 65536
+
+## Tweak GC to run more often
+##-env ERL_FULLSWEEP_AFTER 10
diff --git a/src/release.exs b/src/release.exs
new file mode 100644
index 0000000..8c8ae42
--- /dev/null
+++ b/src/release.exs
@@ -0,0 +1,4 @@
+import Config
+
+{port, ""} = Integer.parse(System.get_env("PORT", "3000"))
+config :lytedev, Lytedev.HttpServer, port: port