Handle referrers so edit flows return users to where they came from (#86)

Author: edwardhorsford

app.js

@@ -1,6 +1,7 @@
 // Core dependencies
 const path = require('path');
 const fs = require('fs');
+const url = require('url')
 
 // External dependencies
 const bodyParser = require('body-parser');
@@ -105,7 +106,7 @@ if (useCookieSessionStore === 'true' && !onlyDocumentation) {
   // Somewhat similar file store to GOV.UK
   const FileStore = require('session-file-store')(sessionInMemory)
   const sessionPath = path.join(__dirname, '.tmp/sessions')
-  
+
   // Make sure the sessions directory exists
   if (!fs.existsSync(sessionPath)) {
     fs.mkdirSync(sessionPath, { recursive: true })
@@ -260,7 +261,11 @@ app.use('/prototype-admin', prototypeAdminRoutes);
 
 // Redirect all POSTs to GETs - this allows users to use POST for autoStoreData
 app.post(/^\/([^.]+)$/, (req, res) => {
-  res.redirect(`/${req.params[0]}`);
+  res.redirect(url.format({
+    pathname: '/' + req.params[0],
+    query: req.query
+  })
+  )
 });
 
 // Catch 404 and forward to error handler

app/lib/utils/referrers.js

@@ -8,29 +8,29 @@
 /**
  * Parse referrer string into array of URLs
  * @private
- * @param {string|Array} referrer - Referrer string or array
+ * @param {string|Array} referrerChain - Referrer string or array
  * @returns {Array} Array of referrer URLs
  */
-const parseReferrerChain = (referrer) => {
-  if (!referrer) return []
-  if (Array.isArray(referrer)) return referrer
-  return referrer.split(',').filter(Boolean)
+const parseReferrerChain = (referrerChain) => {
+  if (!referrerChain) return []
+  if (Array.isArray(referrerChain)) return referrerChain
+  return referrerChain.split(',').filter(Boolean)
 }
 
 /**
  * Get destination from referrer chain, falling back to provided URL if no referrer
  * @param {string} url - Default URL to use if no referrer
- * @param {string} referrer - Referrer chain
+ * @param {string} referrerChain - Referrer chain
  * @returns {string} URL to use for back link
  * @example
  * // In templates:
- * <a href="{{ '/default-path' | orReferrer(referrer) }}">Back</a>
+ * <a href="{{ '/default-path' | getReturnUrl(referrerChain) }}">Back</a>
  */
-const orReferrer = function(url, referrer) {
+const getReturnUrl = function(url, referrerChain) {
   // Get currentUrl from context if available
   const currentUrl = this?.ctx?.currentUrl
 
-  const chain = parseReferrerChain(referrer)
+  const chain = parseReferrerChain(referrerChain)
     .filter(ref => ref !== currentUrl)
 
   if (!chain.length) return url
@@ -42,43 +42,43 @@ const orReferrer = function(url, referrer) {
   const remainingChain = chain.slice(0, -1)
   const destination = chain[chain.length - 1]
 
-  return `${destination}?referrer=${remainingChain.join(',')}`
+  return `${destination}?referrerChain=${remainingChain.join(',')}`
 }
 
 /**
  * Add referrer to URL as query parameter
  * @param {string} url - Base URL
- * @param {string} referrer - Referrer to append
+ * @param {string} referrerChain - Referrer to append
  * @returns {string} URL with referrer query param
  * @example
  * // In templates:
- * <a href="{{ '/next-page' | withReferrer(referrer) }}">Continue</a>
+ * <a href="{{ '/next-page' | urlWithReferrer(referrer) }}">Continue</a>
  */
-const withReferrer = (url, referrer) => {
-  if (!referrer) return url
-  return `${url}?referrer=${referrer}`
+const urlWithReferrer = (url, referrerChain) => {
+  if (!referrerChain) return url
+  return `${url}?referrerChain=${referrerChain}`
 }
 
 /**
  * Append a URL to an existing referrer chain
- * @param {string|Array} existingReferrer - Existing referrer chain
+ * @param {string|Array} existingReferrerChain - Existing referrer chain
  * @param {string} newUrl - URL to append
  * @returns {string} Combined referrer chain
  * @example
  * // In templates:
- * {% set updatedReferrer = referrer | appendReferrer(currentUrl) %}
+ * {% set updatedReferrer = referrerChain | appendReferrer(currentUrl) %}
  */
-const appendReferrer = (existingReferrer, newUrl) => {
-  if (!newUrl) return existingReferrer
-  if (!existingReferrer) return newUrl
+const appendReferrer = (existingReferrerChain, newUrl) => {
+  if (!newUrl) return existingReferrerChain
+  if (!existingReferrerChain) return newUrl
 
   const chain = parseReferrerChain(existingReferrer)
   chain.push(newUrl)
   return chain.join(',')
 }
 
 module.exports = {
-  orReferrer,
-  withReferrer,
+  getReturnUrl,
+  urlWithReferrer,
   appendReferrer,
 }

app/locals.js

@@ -7,7 +7,7 @@ module.exports = (config) => (req, res, next) => {
     currentUrl: req.path,
     flash: req.flash(),
     query: req.query,
-    referrer: req.query.referrer
+    referrerChain: req.query.referrerChain
   }
 
   // Assign all local variables at once

app/routes/clinics.js

@@ -3,6 +3,8 @@
 const dayjs = require('dayjs')
 const { getFilteredClinics, getClinicEvents } = require('../lib/utils/clinics')
 const { filterEventsByStatus } = require('../lib/utils/status')
+const { getReturnUrl, urlWithReferrer, appendReferrer } = require('../lib/utils/referrers')
+
 
 /**
  * Get clinic and its related data from id
@@ -210,7 +212,7 @@ module.exports = router => {
     const data = req.session.data
 
     // Get current filter from query param, or default to the current page's filter
-    const currentFilter = req.query.filter || req.query.currentFilter || 'all'
+    const currentFilter = req.query.filter || req.query.currentFilter || 'remaining'
 
     // Find the event
     const eventIndex = data.events.findIndex(e => e.id === eventId && e.clinicId === clinicId)
@@ -257,13 +259,9 @@ module.exports = router => {
       })
     }
 
-    // If there's a returnTo path, use that, otherwise go back to the filter view
-    const referrer = req.query.referrer
-    if (referrer) {
-      res.redirect(referrer)
-    } else {
-      res.redirect(`/clinics/${clinicId}/${currentFilter}`)
-    }
+    const returnUrl = getReturnUrl(`/clinics/${clinicId}/${currentFilter}`, req.query.referrerChain)
+    res.redirect(returnUrl)
+
   })
 
 
@@ -273,6 +271,12 @@ module.exports = router => {
   // Support both /clinics/:id and /clinics/:id/:filter
   router.get(['/clinics/:id', '/clinics/:id/:filter'], (req, res, next) => {
 
+    // Remaining is our default, so we can redirect to /clinics/:id
+    if (req.params.filter == 'remaining'){
+      res.redirect(`/clinics/${req.params.id}`)
+      return
+    }
+
     // Check filter from either URL param or query string
     let defaultFilter = 'remaining'
     const filter = req.params.filter || req.query.filter || defaultFilter

app/routes/events.js

@@ -5,6 +5,7 @@ const { getFullName } = require('../lib/utils/participants')
 const { generateMammogramImages } = require('../lib/generators/mammogram-generator')
 const { getEvent, saveTempEventToEvent, updateEventStatus } = require('../lib/utils/event-data')
 const generateId = require('../lib/utils/id-generator')
+const { getReturnUrl, urlWithReferrer, appendReferrer } = require('../lib/utils/referrers')
 
 /**
  * Get single event and its related data
@@ -282,7 +283,7 @@ module.exports = router => {
     const { clinicId, eventId } = req.params
     const data = req.session.data
     const action = req.body.action // 'save' or 'save-and-add'
-    const referrer = req.query.referrer
+    const referrerChain = req.query.referrerChain
 
     // Save temp symptom to array
     if (data.event?.symptomTemp) {
@@ -384,13 +385,10 @@ module.exports = router => {
 
     // Redirect based on action
     if (action === 'save-and-add') {
-      res.redirect(`/clinics/${clinicId}/events/${eventId}/medical-information/symptoms/add`)
+      res.redirect(urlWithReferrer(`/clinics/${clinicId}/events/${eventId}/medical-information/symptoms/add`, referrerChain))
     } else {
-      if (referrer) {
-        res.redirect(referrer)
-        return;
-      }
-      res.redirect(`/clinics/${clinicId}/events/${eventId}/record-medical-information`)
+      const returnUrl = getReturnUrl(`/clinics/${clinicId}/events/${eventId}/record-medical-information`, referrerChain)
+      res.redirect(returnUrl)
     }
   })
 
@@ -417,7 +415,7 @@ module.exports = router => {
     }
 
     // Go directly to details page since we already know the type
-    res.redirect(`/clinics/${clinicId}/events/${eventId}/medical-information/symptoms/details`)
+    res.redirect(urlWithReferrer(`/clinics/${clinicId}/events/${eventId}/medical-information/symptoms/details`, req.query.referrerChain))
   })
 
   // Delete symptom
@@ -437,13 +435,14 @@ module.exports = router => {
 
     req.flash('success', 'Symptom deleted')
 
-    res.redirect(`/clinics/${clinicId}/events/${eventId}/record-medical-information`)
+    const returnUrl = getReturnUrl(`/clinics/${clinicId}/events/${eventId}/record-medical-information`, req.query.referrerChain)
+    res.redirect(returnUrl)
   })
 
   // Main route in to starting an event - used to clear any temp data
   router.get('/clinics/:clinicId/events/:eventId/medical-information/symptoms/add', (req, res) => {
     delete req.session.data.event.symptomTemp
-    res.redirect(`/clinics/${req.params.clinicId}/events/${req.params.eventId}/medical-information/symptoms/type`)
+    res.redirect(urlWithReferrer(`/clinics/${req.params.clinicId}/events/${req.params.eventId}/medical-information/symptoms/type`, req.query.referrerChain))
   })
 
   const MAMMOGRAPHY_VIEWS = [

app/views/_components/event-status/template.njk

@@ -16,10 +16,11 @@
 
   {# Build href with optional referrer #}
   {% set href -%}
-  /clinics/{{ params.clinicId }}/check-in/{{ params.event.id }}
-  {%- if params.referrer %}?referrer={{ params.referrer }}{% endif %}
+    /clinics/{{ params.clinicId }}/check-in/{{ params.event.id }}
   {%- endset %}
 
+  {% set href = href | trim | urlWithReferrer(params.referrerChain) %}
+
   {% if params.event.status === 'event_scheduled' %}
     <p class="nhsuk-u-margin-top-2 nhsuk-u-margin-bottom-0">
       <a href="{{ href | trim }}" class="nhsuk-link nhsuk-link--no-visited-state js-check-in-link" data-clinic-id="{{ params.clinicId }}"

app/views/_includes/cards/medical-information/other-information.njk

@@ -93,7 +93,7 @@
       actions: {
         items: [
           {
-            href: "./medical-information/hormone-replacement-therapy",
+            href: "./medical-information/hormone-replacement-therapy" | urlWithReferrer(currentUrl),
             text: "Change",
             visuallyHiddenText: "hormone replacement therapy (HRT)"
           }
@@ -110,7 +110,7 @@
       actions: {
         items: [
           {
-            href: "./medical-information/pregnancy-and-breastfeeding",
+            href: "./medical-information/pregnancy-and-breastfeeding" | urlWithReferrer(currentUrl),
             text: "Change",
             visuallyHiddenText: "pregnancy and breastfeeding"
           }

app/views/_includes/cards/medical-information/symptoms.njk

@@ -14,8 +14,12 @@
     }) }}
   {% endif %}
 
+  {% set linkHref %}
+    {{ "./medical-information/symptoms/add" | urlWithReferrer(currentUrl) }}
+  {% endset %}
+
   <p class="nhsuk-u-margin-top-4 nhsuk-u-margin-bottom-0">
-    <a href="./medical-information/symptoms/add" class="nhsuk-link">{{ "Add another symptom" if hasSymptoms else "Add a symptom" }}</a>
+    <a href="{{ linkHref }}" class="nhsuk-link">{{ "Add another symptom" if hasSymptoms else "Add a symptom" }}</a>
   </p>
 {% endset %}
 

app/views/_includes/event-header.njk

@@ -5,7 +5,7 @@
 {{ eventStatus({
   clinicId: clinicId,
   event: event,
-  referrer: currentUrl
+  referrerChain: currentUrl
 })}}
 {% endset %}
 
@@ -29,5 +29,5 @@
 
 <p>{{ event.timing.startTime | formatTimeString }} ({{ event.timing.duration }} minutes) - {{ clinic.date | formatDate }} ({{ clinic.date | formatRelativeDate }})<span class="nhsuk-u-margin-left-3"><a href="#">Reschedule appointment</a></span></p>
 
-<p class="nhsuk-u-margin-bottom-4"><a href="{{ '/participants/' + participant.id | withReferrer(currentUrl) }}">View participant record</a></p>
+<p class="nhsuk-u-margin-bottom-4"><a href="{{ '/participants/' + participant.id | urlWithReferrer(currentUrl) }}">View participant record</a></p>
 

app/views/_includes/screening-cannot-proceed-link.njk

@@ -1 +1,4 @@
-<p class="nhsuk-u-margin-top-x9"><a class="nhsuk-link nhsuk-link--no-visited-state" href="./attended-not-screened-reason">Appointment cannot proceed</a></p>
+<p class="">
+  <a class="nhsuk-link nhsuk-link--no-visited-state" href="./attended-not-screened-reason">Appointment cannot proceed
+  </a>
+</p>