defmodule Mix.Tasks.Phx.Gen.Release do
@shortdoc "Generates release files and optional Dockerfile for release-based deployments"
@moduledoc """
Generates release files and optional Dockerfile for release-based deployments.
The following release files are created:
* `lib/app_name/release.ex` - A release module containing tasks for running
migrations inside a release
* `rel/overlays/bin/migrate` - A migrate script for conveniently invoking
the release system migrations
* `rel/overlays/bin/server` - A server script for conveniently invoking
the release system with environment variables to start the phoenix web server
Note, the `rel/overlays` directory is copied into the release build by default when
running `mix release`.
To skip generating the migration-related files, use the `--no-ecto` flag. To
force these migration-related files to be generated, the use `--ecto` flag.
## Docker
When the `--docker` flag is passed, the following docker files are generated:
* `Dockerfile` - The Dockerfile for use in any standard docker deployment
* `.dockerignore` - A docker ignore file with standard elixir defaults
For extended release configuration, the `mix release.init`task can be used
in addition to this task. See the `Mix.Release` docs for more details.
"""
use Mix.Task
require Logger
@doc false
def run(args) do
opts = parse_args(args)
if Mix.Project.umbrella?() do
Mix.raise("""
mix phx.gen.release is not supported in umbrella applications.
Run this task in your web application instead.
""")
end
app = Mix.Phoenix.otp_app()
app_namespace = Mix.Phoenix.base()
web_namespace = app_namespace |> Mix.Phoenix.web_module() |> inspect()
binding = [
app_namespace: app_namespace,
otp_app: app,
assets_dir_exists?: File.dir?("assets")
]
Mix.Phoenix.copy_from(paths(), "priv/templates/phx.gen.release", binding, [
{:eex, "rel/server.sh.eex", "rel/overlays/bin/server"},
{:eex, "rel/server.bat.eex", "rel/overlays/bin/server.bat"}
])
if opts.ecto do
Mix.Phoenix.copy_from(paths(), "priv/templates/phx.gen.release", binding, [
{:eex, "rel/migrate.sh.eex", "rel/overlays/bin/migrate"},
{:eex, "rel/migrate.bat.eex", "rel/overlays/bin/migrate.bat"},
{:eex, "release.ex", Mix.Phoenix.context_lib_path(app, "release.ex")}
])
end
if opts.docker do
gen_docker(binding)
end
File.chmod!("rel/overlays/bin/server", 0o755)
File.chmod!("rel/overlays/bin/server.bat", 0o755)
if opts.ecto do
File.chmod!("rel/overlays/bin/migrate", 0o755)
File.chmod!("rel/overlays/bin/migrate.bat", 0o755)
end
Mix.shell().info("""
Your application is ready to be deployed in a release!
See https://hexdocs.pm/mix/Mix.Tasks.Release.html for more information about Elixir releases.
#{if opts.docker, do: docker_instructions()}
Here are some useful release commands you can run in any release environment:
# To build a release
mix release
# To start your system with the Phoenix server running
_build/dev/rel/#{app}/bin/server
#{if opts.ecto, do: ecto_instructions(app)}
Once the release is running you can connect to it remotely:
_build/dev/rel/#{app}/bin/#{app} remote
To list all commands:
_build/dev/rel/#{app}/bin/#{app}
""")
if opts.ecto do
post_install_instructions("config/runtime.exs", ~r/ECTO_IPV6/, """
[warn] Conditional IPV6 support missing from runtime configuration.
Add the following to your config/runtime.exs:
maybe_ipv6 = if System.get_env("ECTO_IPV6"), do: [:inet6], else: []
config :#{app}, #{app_namespace}.Repo,
...,
socket_options: maybe_ipv6
""")
end
post_install_instructions("config/runtime.exs", ~r/PHX_SERVER/, """
[warn] Conditional server startup is missing from runtime configuration.
Add the following to the top of your config/runtime.exs:
if System.get_env("PHX_SERVER") do
config :#{app}, #{web_namespace}.Endpoint, server: true
end
""")
post_install_instructions("config/runtime.exs", ~r/PHX_HOST/, """
[warn] Environment based URL export is missing from runtime configuration.
Add the following to your config/runtime.exs:
host = System.get_env("PHX_HOST") || "example.com"
config :#{app}, #{web_namespace}.Endpoint,
...,
url: [host: host, port: 443]
""")
end
defp parse_args(args) do
args
|> OptionParser.parse!(strict: [ecto: :boolean, docker: :boolean])
|> elem(0)
|> Keyword.put_new_lazy(:ecto, &ecto_sql_installed?/0)
|> Keyword.put_new(:docker, false)
|> Map.new()
end
defp ecto_instructions(app) do
"""
# To run migrations
_build/dev/rel/#{app}/bin/migrate
"""
end
defp docker_instructions do
"""
Using the generated Dockerfile, your release will be bundled into
a Docker image, ready for deployment on platforms that support Docker.
For more information about deploying with Docker see
https://hexdocs.pm/phoenix/releases.html#containers
"""
end
defp paths do
[".", :phoenix]
end
defp post_install_instructions(path, matching, msg) do
case File.read(path) do
{:ok, content} ->
unless content =~ matching, do: Mix.shell().info(msg)
{:error, _} ->
Mix.shell().info(msg)
end
end
defp ecto_sql_installed?, do: Mix.Project.deps_paths() |> Map.has_key?(:ecto_sql)
@debian "bullseye"
defp gen_docker(binding) do
elixir_vsn = System.version()
otp_vsn = otp_vsn()
url =
"https://hub.docker.com/v2/namespaces/hexpm/repositories/elixir/tags?name=#{elixir_vsn}-erlang-#{otp_vsn}-debian-#{@debian}-"
debian_vsn =
fetch_body!(url)
|> Phoenix.json_library().decode!()
|> Map.fetch!("results")
|> Enum.find_value(:error, fn %{"name" => name} ->
if String.ends_with?(name, "-slim") do
%{"vsn" => vsn} = Regex.named_captures(~r/.*debian-#{@debian}-(?<vsn>.*)-slim/, name)
{:ok, vsn}
end
end)
case debian_vsn do
{:ok, debian_vsn} ->
binding =
Keyword.merge(binding,
debian: @debian,
debian_vsn: debian_vsn,
elixir_vsn: elixir_vsn,
otp_vsn: otp_vsn
)
Mix.Phoenix.copy_from(paths(), "priv/templates/phx.gen.release", binding, [
{:eex, "Dockerfile.eex", "Dockerfile"},
{:eex, "dockerignore.eex", ".dockerignore"}
])
:error ->
raise "unable to fetch supported Docker image for Elixir #{elixir_vsn} and Erlang #{otp_vsn}"
end
end
defp fetch_body!(url) do
url = String.to_charlist(url)
Logger.debug("Fetching latest image information from #{url}")
{:ok, _} = Application.ensure_all_started(:inets)
{:ok, _} = Application.ensure_all_started(:ssl)
if proxy = System.get_env("HTTP_PROXY") || System.get_env("http_proxy") do
Logger.debug("Using HTTP_PROXY: #{proxy}")
%{host: host, port: port} = URI.parse(proxy)
:httpc.set_options([{:proxy, {{String.to_charlist(host), port}, []}}])
end
if proxy = System.get_env("HTTPS_PROXY") || System.get_env("https_proxy") do
Logger.debug("Using HTTPS_PROXY: #{proxy}")
%{host: host, port: port} = URI.parse(proxy)
:httpc.set_options([{:https_proxy, {{String.to_charlist(host), port}, []}}])
end
# https://erlef.github.io/security-wg/secure_coding_and_deployment_hardening/inets
http_options = [
ssl: [
verify: :verify_peer,
cacertfile: String.to_charlist(CAStore.file_path()),
depth: 3,
customize_hostname_check: [
match_fun: :public_key.pkix_verify_hostname_match_fun(:https)
],
versions: protocol_versions()
]
]
case :httpc.request(:get, {url, []}, http_options, body_format: :binary) do
{:ok, {{_, 200, _}, _headers, body}} -> body
other -> raise "couldn't fetch #{url}: #{inspect(other)}"
end
end
defp protocol_versions do
otp_major_vsn = :erlang.system_info(:otp_release) |> List.to_integer()
if otp_major_vsn < 25, do: [:"tlsv1.2"], else: [:"tlsv1.2", :"tlsv1.3"]
end
def otp_vsn do
major = to_string(:erlang.system_info(:otp_release))
path = Path.join([:code.root_dir(), "releases", major, "OTP_VERSION"])
case File.read(path) do
{:ok, content} ->
String.trim(content)
{:error, _} ->
IO.warn("unable to read OTP minor version at #{path}. Falling back to #{major}.0")
"#{major}.0"
end
end
end
