Phoenix: Phoenix 1.3.0-rc3 mix phx.server hangs with MIX_ENV=prod

Created on 24 Jul 2017 · 10Comments · Source: phoenixframework/phoenix

Environment

Elixir version (elixir -v): 1.4.4
Phoenix version (mix deps): 1.3.0-rc3
NodeJS version (node -v): 7.7.4
NPM version (npm -v): 4.1.2
Operating system: MacOS Sierra 10.12.4

Expected behavior

MIX_ENV=prod mix phx.server starts the server.

Actual behavior

MIX_ENV=prod mix phx.server hangs and never starts up.

Reproduced in current project locally and on production (Heroku), as well as a brand new project.

open for guidance

Source

johnmosesman

Most helpful comment

It is actually a backwards incompatible change between the release candidates. This configuration is no longer supported: https://github.com/johnmosesman/phoenix_1.3.0-rc3_bug/blob/master/config/prod.exs#L17

Instead of on_init, do this in your config:

load_from_system_env: true,

and then in your endpoint:

@doc """
  Callback invoked for dynamically configuring the endpoint.

  It receives the endpoint configuration and checks if
  configuration should be loaded from the system environment.
  """
  def init(_key, config) do
    if config[:load_from_system_env] do
      port = System.get_env("PORT") || raise "expected the PORT environment variable to be set"
      {:ok, Keyword.put(config, :http, [:inet6, port: port])}
    else
      {:ok, config}
    end
  end

@chrismccord can you please make sure this is in the release announcements?

josevalim on 25 Jul 2017

👍3

All 10 comments

Seconding - I paired on this. Seems like something broke since the last rc.

nathanl on 24 Jul 2017

👍1

We couldn't see anything in the logs that told us why it was hanging; we just saw that it timed out before binding to the port and was restarted (this is on Heroku).

nathanl on 24 Jul 2017

Instead of on_init, do this in your config:

load_from_system_env: true,

and then in your endpoint:

@doc """
  Callback invoked for dynamically configuring the endpoint.

  It receives the endpoint configuration and checks if
  configuration should be loaded from the system environment.
  """
  def init(_key, config) do
    if config[:load_from_system_env] do
      port = System.get_env("PORT") || raise "expected the PORT environment variable to be set"
      {:ok, Keyword.put(config, :http, [:inet6, port: port])}
    else
      {:ok, config}
    end
  end

@chrismccord can you please make sure this is in the release announcements?

josevalim on 25 Jul 2017

👍3

Let's leave this open for guidance.

josevalim on 25 Jul 2017

Done

chrismccord on 25 Jul 2017

@chrismccord @josevalim thanks!

Is this something that could be changed in mix phx.new to set it up correctly?

johnmosesman on 25 Jul 2017

rc.3 does not generate that code. So you either have two archives installed or you generated the app using rc.2 and Hex picked up rc.3. :) I have also added a warning to master that will hopefully aid future migrations.

josevalim on 25 Jul 2017

Is this issue still relevant now that 1.3.0 has been released? to help you guys clean the list of issues :)