From d15543aec42be5892d1f2e99db06c84e055ba6a5 Mon Sep 17 00:00:00 2001
From: Joe Lanman <joelanman@gmail.com>
Date: Tue, 17 Jul 2018 16:50:48 +0100
Subject: [PATCH] create v6 app to serve old prototype files from app/v6

---
 lib/utils.js |  4 +--
 server.js    | 69 +++++++++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 67 insertions(+), 6 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index 2f78e5f8ec..8131c50b7a 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -195,13 +195,13 @@ exports.getLatestRelease = function () {
 // Try to match a request to a template, for example a request for /test
 // would look for /app/views/test.html
 // or /app/views/text/index.html
-exports.matchRoutes = function (req, res) {
+exports.matchRoutes = function (req, res, next) {
   var path = (req.params[0])
   res.render(path, function (err, html) {
     if (err) {
       res.render(path + '/index', function (err2, html) {
         if (err2) {
-          res.status(404).send(err + '<br>' + err2)
+          next()
         } else {
           res.end(html)
         }
diff --git a/server.js b/server.js
index 0dd22d3c22..1125c7e568 100644
--- a/server.js
+++ b/server.js
@@ -18,8 +18,24 @@ const packageJson = require('./package.json')
 const routes = require('./app/routes.js')
 const utils = require('./lib/utils.js')
 
+var useV6 = false
+var v6App
+var v6Routes
+
+try {
+  v6Routes = require('./app/v6/routes.js')
+  useV6 = true
+} catch (e) {
+  // No routes.js in app/v6 so we can continue with useV6 false
+}
+
 const app = express()
 const documentationApp = express()
+
+if (useV6) {
+  v6App = express()
+}
+
 dotenv.config()
 
 // Set cookies for use in cookie banner.
@@ -123,6 +139,32 @@ app.use(bodyParser.urlencoded({
   extended: true
 }))
 
+// Set up v6 app for backwards compatibility
+if (useV6) {
+  var v6Views = [
+    path.join(__dirname, '/node_modules/govuk_template_jinja/views/layouts'),
+    path.join(__dirname, '/app/v6/views/'),
+    path.join(__dirname, '/lib/')
+  ]
+
+  var nunjucksv6Env = nunjucks.configure(v6Views, {
+    autoescape: true,
+    express: v6App,
+    noCache: true,
+    watch: true
+  })
+  // Nunjucks filters
+  utils.addNunjucksFilters(nunjucksv6Env)
+
+  // Set views engine
+  v6App.set('view engine', 'html')
+
+  // Backward compatibility with GOV.UK Elements
+  app.use('/public/v6/', express.static(path.join(__dirname, '/node_modules/govuk_template_jinja/assets')))
+  app.use('/public/v6/', express.static(path.join(__dirname, '/node_modules/govuk_frontend_toolkit')))
+  app.use('/public/v6/javascripts/govuk/', express.static(path.join(__dirname, '/node_modules/govuk_frontend_toolkit/javascripts/govuk/')))
+}
+
 // Add global variable to determine if DoNotTrack is enabled.
 // This indicates a user has explicitly opted-out of tracking.
 // Therefore we can avoid injecting third-party scripts that do not respect this decision.
@@ -225,6 +267,18 @@ if (useDocumentation) {
   documentationApp.use('/', documentationRoutes)
 }
 
+if (useV6) {
+  // Clone app locals to v6 app locals
+  v6App.locals = Object.assign({}, app.locals)
+  v6App.locals.asset_path = '/public/v6/'
+
+  // Create separate router for v6
+  app.use('/', v6App)
+
+  // Docs under the /docs namespace
+  v6App.use('/', v6Routes)
+}
+
 // Strip .html and .htm if provided
 app.get(/\.html?$/i, function (req, res) {
   var path = req.path
@@ -237,19 +291,26 @@ app.get(/\.html?$/i, function (req, res) {
 // Auto render any view that exists
 
 // App folder routes get priority
-app.get(/^\/([^.]+)$/, function (req, res) {
-  utils.matchRoutes(req, res)
+app.get(/^\/([^.]+)$/, function (req, res, next) {
+  utils.matchRoutes(req, res, next)
 })
 
 if (useDocumentation) {
   // Documentation  routes
-  documentationApp.get(/^\/([^.]+)$/, function (req, res) {
+  documentationApp.get(/^\/([^.]+)$/, function (req, res, next) {
     if (!utils.matchMdRoutes(req, res)) {
-      utils.matchRoutes(req, res)
+      utils.matchRoutes(req, res, next)
     }
   })
 }
 
+if (useV6) {
+  // App folder routes get priority
+  v6App.get(/^\/([^.]+)$/, function (req, res, next) {
+    utils.matchRoutes(req, res, next)
+  })
+}
+
 // Redirect all POSTs to GETs - this allows users to use POST for autoStoreData
 app.post(/^\/([^.]+)$/, function (req, res) {
   res.redirect('/' + req.params[0])