Redirect old CSV preview URLs

After the new /csv-preview URL is in place, we need to redirect
asset URLs with /media/…/prefix to the new URL.

Author: catalinailie

app/controllers/csv_preview_controller.rb

@@ -8,8 +8,8 @@ def show
     @asset = GdsApi.asset_manager.asset(params[:id]).to_hash
 
     return error_410 if @asset["deleted"] || @asset["redirect_url"].present?
-    if draft_asset? && served_from_asset_host?
-      redirect_to(Plek.find("draft-assets") + request.path, allow_other_host: true) and return
+    if draft_asset? && served_from_origin_host?
+      redirect_to(Plek.find("draft-origin", external: true) + request.path, allow_other_host: true) and return
     end
 
     parent_document_uri = @asset["parent_document_url"]
@@ -52,7 +52,7 @@ def draft_asset?
     @asset["draft"] == true
   end
 
-  def served_from_asset_host?
-    request.hostname == URI.parse(Plek.find("assets")).hostname
+  def served_from_origin_host?
+    request.hostname == URI.parse(Plek.find("www", external: true)).hostname
   end
 end

app/controllers/csv_preview_redirect_controller.rb

@@ -0,0 +1,18 @@
+class CsvPreviewRedirectController < ApplicationController
+  before_action { expires_in(1.day, public: true) }
+
+  def redirect
+    csv_preview_path = "/csv-preview/#{params[:id]}/#{params[:filename]}"
+    host = served_from_draft_asset_host? ? Plek.find("draft-origin", external: true) : Plek.find("www", external: true)
+
+    redirect_to(host + csv_preview_path,
+                status: :moved_permanently,
+                allow_other_host: true)
+  end
+
+private
+
+  def served_from_draft_asset_host?
+    request.hostname == URI.parse(Plek.find("draft-assets")).hostname
+  end
+end

config/routes.rb

@@ -78,7 +78,7 @@
   get "/find-licences/:slug/:authority_slug/:interaction", to: "licence_transaction#authority_interaction", as: "licence_transaction_authority_interaction"
 
   # Old style media previews (compatible with preview_url)
-  get "/media/:id/:filename/preview", to: "csv_preview#show", filename: /[^\/]+/
+  get "/media/:id/:filename/preview", to: "csv_preview_redirect#redirect", filename: /[^\/]+/
   # New style CSV previews (using a different path to avoid the special routing for preview_url)
   get "/csv-preview/:id/:filename", to: "csv_preview#show", filename: /[^\/]+/, defaults: { format: "html" }
 

spec/requests/csv_preview_spec.rb

@@ -16,7 +16,7 @@
     end
 
     it "redirects to parent" do
-      get "/#{path_from_filename(asset_manager_filename)}/preview"
+      get "/csv-preview/#{asset_manager_id}/#{asset_manager_filename}.csv"
 
       expect(response).to redirect_to(parent_document_url)
     end
@@ -29,7 +29,7 @@
     end
 
     it "redirects to parent" do
-      get "/#{path_from_filename(asset_manager_filename)}/preview"
+      get "/csv-preview/#{asset_manager_id}/#{asset_manager_filename}.csv"
 
       expect(response).to have_http_status(:not_found)
     end

spec/routing/csv_previews_spec.rb

@@ -1,8 +1,8 @@
 RSpec.describe "CSV previews" do
   it "routes old style paths to the CsvPreviewController" do
     expect(get("/media/000000000000000000000000/some-file.csv/preview")).to route_to(
-      controller: "csv_preview",
-      action: "show",
+      controller: "csv_preview_redirect",
+      action: "redirect",
       id: "000000000000000000000000",
       filename: "some-file.csv",
     )

spec/system/csv_preview_spec.rb

@@ -135,11 +135,11 @@
     before do
       asset_manager_response = { id: "https://asset-manager.dev.gov.uk/assets/foo", parent_document_url:, draft: true }
       stub_asset_manager_has_an_asset(asset_manager_id, asset_manager_response, "/#{filename}.csv")
-      visit "http://assets.dev.gov.uk//#{asset_media_url_path}/preview"
+      visit "http://assets.dev.gov.uk/#{asset_media_url_path}/preview"
     end
 
     it "redirects to the draft assets host" do
-      expect(current_url).to eq("http://draft-assets.dev.gov.uk/#{asset_media_url_path}/preview")
+      expect(current_url).to eq("http://draft-origin.dev.gov.uk/csv-preview/#{asset_manager_id}/#{filename}.csv")
     end
   end