before { host! "api.example.com" }
host! the method allows controlling host sent in RSpec tests.
Adding it to RSpec
# spec/support/subdomain_helpers.rb
module SubdomainHelper
def within_subdomain(subdomain)
before { host! "#{subdomain}.server.local" }
after { host! "www.server.local" }
yield
end
end
# spec/rails_spec.rb
config.extend SubdomainHelper, type: :request
Then using it in RSpec tests
RSpec.describe "API call", type: :request do
within_subdomain :api do
describe "method" do
it "checks request host" do
get api_path
expect(response.host).to eq("api.server.local")
end
end
end
end