Phoenix uses wrong port


I created a new Phoenix umbrella application. I am trying to configure it to use different port, but the port does not change.

$ mix test --umbrella --no-ecto

In test_umbrella/config/prod.exs:

I uncommented this line:

config :test_web, TestWeb.Endpoint, server: true

and configured the ip and the port:

config :test_web, TestWeb.Endpoint,
  url: [ip: [0,0,0,0], port: 1234],
  cache_static_manifest: "priv/static/cache_manifest.json"

Then I ran:

$ cd test_umbrella/
$ SECRET_KEY_BASE=$(mix phx.gen.secret) MIX_ENV=prod mix phx.server

The server starts, but cowboy listens on port 4000 instead of 1234.

08:14:34.496 [info] Running TestWeb.Endpoint with cowboy 2.6.3 at :::4000 (http)
08:14:34.498 [info] Access TestWeb.Endpoint at http://localhost:1234
08:15:13.928 request_id=Fa1_NZgFyPdDboEAACYH [info] GET /
08:15:13.929 request_id=Fa1_NZgFyPdDboEAACYH [info] Sent 200 in 1ms

$ curl
curl: (7) Failed to connect to port 1234: Connection refused
$ curl
curl: (7) Failed to connect to port 1234: Connection refused
$ curl
<!DOCTYPE html>
<html lang="en">
    <meta charset="utf-8"/>

Some additional information:

$ elixir --version
Erlang/OTP 22 [erts-10.4.3] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [hipe] [dtrace]
Elixir 1.9.0 (compiled with Erlang/OTP 22)

$ mix --version
Phoenix v1.4.8

$ uname -a
Darwin MBPro.local 18.6.0 Darwin Kernel Version 18.6.0: Thu Apr 25 23:16:27 PDT 2019; root:xnu- 
4903.261.4~2/RELEASE_X86_64 x86_64

Ah yes. I have to use the PORT environment variable:

$ PORT=1234 SECRET_KEY_BASE=$(mix phx.gen.secret) MIX_ENV=prod mix phx.server

Is this a bug? What happens if I use different port in the configuration file?

Just changing prod.exs might not necessarily help. Especially in an umbrella project you need to be very sure about when to edit which file.

This though is dependant on you overall config structure.

Just open your umbrellas root config/config.exs and try to play through the load_config calls and see if you end up in your applications config/prod.exs.

1 Like

You must have somewhere something like System.get_env("PORT") or {:system, "PORT"}. Try finding it in your project, you will learn where it’s being set and apparently it overwrites your configuration of prod.exs

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Thanks! I found this in test_umbrella/config/prod.secret.exs.

config :test_web, TestWeb.Endpoint,
  http: [:inet6, port: String.to_integer(System.get_env("PORT") || "4000")],
  secret_key_base: secret_key_base

Changing the port here works. I think I will configure my application to use the environment variable everywhere.


Glad I could help.

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In short: The :http config is for listening part, while the :url config is for the url/link generation.