Using (multiple) subdomains; change base URL like Cypress’ Config API (ish) …?

[cabgfx]

First of all, thank you for putting this out in the world 🙏

What I'm trying to do:
Run specs across two different subdomains, eg.

// app_area_1.spec.js
context('Trying', () => {
  it('tries', () => {
    cy.visit("http://subdomain1.lvh.me")
    …
  });
});

// app_area_2.spec.js
   …
   cy.visit("http://subdomain2.lvh.me")
   …

My app has two routing constraints, based on subdomain. They are distinct parts of the app, ie. different controllers, views, etc. Somewhat similar to multi-tenancy, or admin/public namespaced apps, so I'd suspect this use case of testing across subdomains might come up for others?

What I've tried:
I've tried this option , continuing from the example above:

// app_area_1.spec.js
Cypress.config("baseUrl", "http://subdomain1.lvh.me")

context('Trying', () => {
  it('tries', () => { …

// app_area_2.spec.js
Cypress.config("baseUrl", "http://subdomain2.lvh.me")

context('Trying', () => {
   …

The base URL is changed alright, but Cypress isn't going anywhere, since Puma was booted on default 127.0.0.1.

(To be clear, the spec runs correctly whenever ENV['CYPRESS_RAILS_HOST'] matches config.baseUrl.)

Where I'm stuck:

1. Is ENV['CYPRESS_RAILS_HOST'] the only way to set config.host ? I realize this gem says on the tin, “The cypress-rails gem is configured entirely via environment variables.”, so I could see how it would be?
2. What would be necessary to support (some of) Cypress’ options to override eg. baseUrl?

Thanks in advance for considering my issue!

---

Background/paper trail:

• I've read up on configuration for this gem, env vars specifically
• Tried combinations of CYPRESS_RAILS_HOST and baseUrl, omitting one, the other, then both, etc. 👯‍♂️
• Then read up on config.rb, and on how puma starts up to support Cypress
• Familiarized myself with Cypress' general restrictions on changing hosts, eg. across multiple visit‘s in one example
• And finally looked at the options for overriding config in Cypress

Also, I've seen #25 and its follow-up #26 — seems related? You mention this in a closing remark:

(By the way, it occurred to me if you set Cypress.config('baseUrl', '/blah') in a support file instead of Cypress.json, you shouldn't need this option since it'll win over either cypress.json or the ENV flag)

Is that similar to my issue here?

[searls]

Hey thanks for posting this. I haven't gotten a chance to formulate a response yet because issues of domain-level routing logic are complex enough (is it client-side or server-side routing? what kind of request is being made to the domain?) that it's not super clear what fixes I could propose that would fix you.

Can you try to reproduce the scenario you're describing in a minimal repo for me to look at?

[yagudaev]

@cabgfx don't you just need to boot it on -b 0.0.0.0 so the websocket can receive requests from any IP address?

[cabgfx]

boot it on -b 0.0.0.0

Seems possible, @yagudaev and thanks for that! Just so I'm clear, does it here refer to booting Cypres-rails' puma server on 0.0.0.0, or did you mean something else?

And thanks @searls I'll try to elaborate with a repo to show my issue.
FWIW, I mean server side routing, with this in my routes.rb:

Rails.application.routes.draw do
  def subdomain_for(env_var)
    # in development, I have eg. subdomain1.myapp.test (using puma-dev),
    # so when I use subdomain1.lvh.me in specs,
    # the lvh.me domain points back to localhost
    # and Rails will match subdomain1 or subdomain2, with these constraints below
    ActionDispatch::Http::URL.extract_subdomain(ENV[env_var], 1)
  end

  constraints subdomain: subdomain_for("PreshopDomain") do
     # app routing
  end

  constraints subdomain: subdomain_for("WebshopDomain") do
     # app routing
  end

  constraints subdomain: "" do
    get "/", to: redirect(domain: ENV["WebshopDomain"])
  end
end

[yagudaev]

Yeah I did mean the puma server on 0.0.0.0.

What was the 500 error in the server logs?