URL confusion caused by Caddyfile configuration

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1

1. The problem I’m having:

I’m trying to correctly setup an steam openid login implementation but after putting the realm as my domain and the returnUrl as the domain/callback, not localhost it is apparently putting https://https://arenadota.com/callback Why is it doing that? Is it something in my Caddyfile causing that confusion?

For context, the implementation for these two variables are:

this.steamAuth = new SteamAuth({
      realm: `https://arenadota.com`,
      returnUrl: `https://arenadota.com/callback`,
      apiKey: process.env.STEAM_WEB_API_KEY,
    });

2. Error messages and/or full log output:

There are no error messages, thankfully, just that url mixup that is popping up

3. Caddy version:

Caddy v2.9.1

4. How I installed and ran Caddy:

Followed the installation guide for the stable version of caddy for Ubuntu.

a. System environment:

Ubuntu 24.04.2 LTS server

b. Command:

sudo systemctl start caddy

d. My complete Caddy config:

arenadota.com {
        reverse_proxy localhost:5173

        # Set this path to your site's directory.
        # root * /web/frontend/dist

        # Enable the static file server.
        # file_server

        reverse_proxy /callback* localhost:8081
        reverse_proxy /health-check localhost:8081
        reverse_proxy /steam_auth localhost:8081
        reverse_proxy /api/v1* localhost:8081
        # TODO: Bot
}

5. Links to relevant resources:

I’m not using the passport steam strategy, instead, I used the node-steam-openid library since it was easier to implement and didn’t require extensive documentation.

2

It’s not Caddy doing it. Caddy is not the one creating the URLs, so it cannot be the one doing it.