Fail gracefully on DFC product import errors

app/controllers/admin/dfc_product_imports_controller.rb

@@ -38,6 +38,11 @@ module Admin
       end
 
       @count = imported.compact.count
+    rescue Faraday::Error,
+           Addressable::URI::InvalidURIError,
+           ActionController::ParameterMissing => e
+      flash[:error] = e.message
+      redirect_to admin_product_import_path
     end
 
     private

spec/system/admin/dfc_product_import_spec.rb

@@ -76,4 +76,31 @@ RSpec.describe "DFC Product Import" do
     expect(product.variants[0].semantic_links).to be_present
     expect(product.image).to be_present
   end
+
+  it "fails gracefully" do
+    user.oidc_account.update!(
+      uid: "anonymous@example.net",
+      updated_at: 1.minute.ago,
+    )
+    url = "https://example.net/unauthorized"
+    stub_request(:get, url).to_return(status: [401, "Unauthorized"])
+
+    visit admin_product_import_path
+    select enterprise.name, from: "Enterprise"
+    fill_in "catalog_url", with: url
+
+    expect { click_button "Import" }.not_to change { Spree::Variant.count }
+
+    expect(page).to have_content "the server responded with status 401"
+
+    select enterprise.name, from: "Enterprise"
+    fill_in "catalog_url", with: "badurl"
+    click_button "Import"
+    expect(page).to have_content "Absolute URI missing hierarchical segment: 'http://:80'"
+
+    select enterprise.name, from: "Enterprise"
+    fill_in "catalog_url", with: ""
+    click_button "Import"
+    expect(page).to have_content "param is missing or the value is empty: catalog_url"
+  end
 end