Given the following configuration of a phoenix application :
use Mix.Config
config :sitecc, Sitecc.Endpoint,
http: [port: {:system, "PORT"}],
url: [host: "foo", port: {:system, "PORT"}],
cache_static_manifest: "priv/static/manifest.json",
server: true,
root: '.',
version: Mix.Project.config[:version]
My /etc/hosts file aliases “foo” to localhost
// From /etc/hosts
127.0.0.1 localhost foo
When I release a prod version of the application, and start the app with a POST from environment variable (eg 4000), I can connect with a browser using websockets with url "http://foo:4000/".
However, my application will be deployed several time in different production environments, with different hostname.
So I’d like to use an environment variable.
It seems like Phoenix supports that, so I tried as documented here:
config :sitecc, Sitecc.Endpoint,
http: [port: {:system, "PORT"}],
url: [host: {:system, "HOST"}, port: {:system, "PORT"}],
cache_static_manifest: "priv/static/manifest.json",
server: true,
root: '.',
version: Mix.Project.config[:version]
However, when I start the server this way, Websockets connections are refused.
HOST=foo PORT=4000 _build/prod/rel/site/bin/site console
...
16:04:06.295 [error] Could not check origin for Phoenix.Socket transport.
This happens when you are attempting a socket connection to
a different host than the one configured in your config/
files. For example, in development the host is configured
to "localhost" but you may be trying to access it from
"127.0.0.1". To fix this issue, you may either:
1. update [url: [host: ...]] to your actual host in the
config file for your current environment (recommended)
2. pass the :check_origin option when configuring your
endpoint or when configuring the transport in your
UserSocket module, explicitly outlining which origins
are allowed:
check_origin: ["https://example.com",
"//another.com:888", "//other.com"]
Am I missing something ? Is it a bug in elixir ?
The suggested solution (explicitely setting check_origin) has roughly the same issue ; it seems like it is expanded at compile time, and I can not use a function to read the System’s env at startup.
Any idea on how to tackle that ?
