Update links to n8n server

spec/migrations/20240502035220_update_n8n_url_spec.rb

@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require_relative '../../db/migrate/20240502035220_update_n8n_url'
+
+describe UpdateN8nUrl do
+  # We may want to move this to a support file if this syntax is useful in
+  # other places. Reference:
+  # - https://stackoverflow.com/a/34969429/3377535
+  RSpec::Matchers.define_negated_matcher :not_change, :change
+
+  let(:enterprise) { create(:enterprise) }
+  let(:old_data) {
+    {
+      link: "https://link-to-form",
+      destroy: "https://n8n.openfoodnetwork.org.uk/webhook/remove-enterprise?key=abc&id=123",
+    }
+  }
+  let(:new_data) {
+    {
+      link: "https://link-to-form",
+      destroy: "https://n8n.openfoodnetwork.org/webhook/remove-enterprise?key=abc&id=123",
+    }
+  }
+
+  it "updates old connected app links" do
+    app = ConnectedApp.create!(enterprise:, data: old_data,)
+
+    expect {
+      subject.up
+      app.reload
+    }.to change {
+      app.data["destroy"]
+    }.to("https://n8n.openfoodnetwork.org/webhook/remove-enterprise?key=abc&id=123")
+      .and not_change {
+        app.data["link"]
+      }
+  end
+
+  it "keeps new connected app links" do
+    app = ConnectedApp.create!(enterprise:, data: new_data,)
+
+    expect {
+      subject.up
+      app.reload
+    }.not_to change {
+      app.data
+    }
+  end
+end