Fix duplicate purposes in return reqs. set up (#1180)

https://eaflood.atlassian.net/browse/WATER-4592

> Part of the return requirements set up work

During the return requirements set up journey, users need to select at least one purpose for each return requirement they are setting up. The purposes they can choose from are only those linked to the current version of the licence.

The issue found is that if a licence is linked to a purpose and then to a point, then the same purpose again but to a different point (perhaps because it has condition or different abstraction properties), it causes our logic to return the same purpose twice. More if things are really complicated!

This change fixes it so that the user only sees a distinct list of applicable purposes on the 'Select the purpose for the requirements for returns' page.

app/services/return-requirements/fetch-licence-purposes.service.js → app/services/return-requirements/fetch-purposes.service.js

@@ -12,7 +12,7 @@ const PurposeModel = require('../../models/purpose.model.js')
  *
  * @param {string} licenceId - The UUID for the licence to fetch
  *
- * @returns {Promise<Object>} The purposes for the matching licenceId
+ * @returns {Promise<Object>} The distinct purposes for the matching licence's current version
  */
 async function go (licenceId) {
   return _fetch(licenceId)
@@ -24,10 +24,12 @@ async function _fetch (licenceId) {
       'purposes.id',
       'purposes.description'
     ])
-    .innerJoin('licenceVersionPurposes', 'purposes.id', 'licenceVersionPurposes.purposeId')
-    .innerJoin('licenceVersions', 'licenceVersionPurposes.licenceVersionId', 'licenceVersions.id')
-    .where('licenceVersions.licenceId', licenceId)
-    .where('licenceVersions.status', 'current')
+    .whereExists(
+      PurposeModel.relatedQuery('licenceVersionPurposes')
+        .innerJoin('licenceVersions', 'licenceVersions.id', 'licenceVersionPurposes.licenceVersionId')
+        .where('licenceVersions.licenceId', licenceId)
+        .where('licenceVersions.status', 'current')
+    )
     .orderBy([
       { column: 'purposes.description', order: 'asc' }
     ])

app/services/return-requirements/purpose.service.js

@@ -5,7 +5,7 @@
  * @module PurposeService
  */
 
-const FetchLicencePurposesService = require('./fetch-licence-purposes.service.js')
+const FetchPurposesService = require('./fetch-purposes.service.js')
 const SelectPurposePresenter = require('../../presenters/return-requirements/purpose.presenter.js')
 const SessionModel = require('../../models/session.model.js')
 
@@ -22,7 +22,7 @@ const SessionModel = require('../../models/session.model.js')
 */
 async function go (sessionId, requirementIndex) {
   const session = await SessionModel.query().findById(sessionId)
-  const purposesData = await FetchLicencePurposesService.go(session.licence.id)
+  const purposesData = await FetchPurposesService.go(session.licence.id)
 
   const formattedData = SelectPurposePresenter.go(session, requirementIndex, purposesData)
 

app/services/return-requirements/submit-purpose.service.js

@@ -5,7 +5,7 @@
  * @module SubmitPurposeService
  */
 
-const FetchLicencePurposesService = require('./fetch-licence-purposes.service.js')
+const FetchPurposesService = require('./fetch-purposes.service.js')
 const GeneralLib = require('../../lib/general.lib.js')
 const PurposePresenter = require('../../presenters/return-requirements/purpose.presenter.js')
 const PurposeValidation = require('../../validators/return-requirements/purpose.validator.js')
@@ -30,7 +30,7 @@ const SessionModel = require('../../models/session.model.js')
  */
 async function go (sessionId, requirementIndex, payload, yar) {
   const session = await SessionModel.query().findById(sessionId)
-  const licencePurposes = await FetchLicencePurposesService.go(session.licence.id)
+  const licencePurposes = await FetchPurposesService.go(session.licence.id)
 
   _handleOneOptionSelected(payload)
 

test/services/return-requirements/fetch-purposes.service.test.js

@@ -0,0 +1,74 @@
+'use strict'
+
+// Test framework dependencies
+const Lab = require('@hapi/lab')
+const Code = require('@hapi/code')
+
+const { describe, it, beforeEach } = exports.lab = Lab.script()
+const { expect } = Code
+
+// Test helpers
+const LicenceVersionHelper = require('../../support/helpers/licence-version.helper.js')
+const LicenceVersionPurposeHelper = require('../../support/helpers/licence-version-purpose.helper.js')
+const PurposeHelper = require('../../support/helpers/purpose.helper.js')
+
+// Thing under test
+const FetchPurposesService = require('../../../app/services/return-requirements/fetch-purposes.service.js')
+
+describe('Return Requirements - Fetch Purposes service', () => {
+  let licenceVersion
+  let purposes
+
+  beforeEach(async () => {
+    // Create the initial licenceVersion
+    licenceVersion = await LicenceVersionHelper.add()
+
+    // Create 3 purposes. Note - we purposefully don't add them in alphabetical order so we can test they get sorted
+    // by the service
+    purposes = await Promise.all([
+      PurposeHelper.add({ description: 'Large Garden Watering' }),
+      PurposeHelper.add({ description: 'Heat Pump' }),
+      PurposeHelper.add({ description: 'Horticultural Watering' })
+    ])
+
+    // Create the licenceVersionPurposes. Note - two of them are for the same purpose. This is common in the service
+    // where, for example, a licence might abstract water from 2 different points for the same purpose, but they were
+    // set up separately (rather than the licence version purpose being linked to multiple points) because the details
+    // and/or conditions are different at the 2 points.
+    const licenceVersionId = licenceVersion.id
+
+    await Promise.all([
+      LicenceVersionPurposeHelper.add({ licenceVersionId, purposeId: purposes[0].id }),
+      LicenceVersionPurposeHelper.add({ licenceVersionId, purposeId: purposes[1].id }),
+      LicenceVersionPurposeHelper.add({ licenceVersionId, purposeId: purposes[1].id }),
+      LicenceVersionPurposeHelper.add({ licenceVersionId, purposeId: purposes[2].id })
+    ])
+  })
+
+  describe('when called with a valid licenceId', () => {
+    it('fetches the data', async () => {
+      const result = await FetchPurposesService.go(licenceVersion.licenceId)
+
+      expect(result[0]).to.equal({
+        id: purposes[1].id,
+        description: 'Heat Pump'
+      })
+      expect(result[1]).to.equal({
+        id: purposes[2].id,
+        description: 'Horticultural Watering'
+      })
+      expect(result[2]).to.equal({
+        id: purposes[0].id,
+        description: 'Large Garden Watering'
+      })
+    })
+  })
+
+  describe('when called with an invalid licenceId', () => {
+    it('returns an empty result', async () => {
+      const result = await FetchPurposesService.go('5505ca34-270a-4dfb-894c-168c8a4d6e23')
+
+      expect(result).to.be.empty()
+    })
+  })
+})

test/services/return-requirements/purpose.service.test.js

@@ -13,7 +13,7 @@ const DatabaseSupport = require('../../support/database.js')
 const SessionHelper = require('../../support/helpers/session.helper.js')
 
 // Things we need to stub
-const FetchLicencePurposesService = require('../../../app/services/return-requirements/fetch-licence-purposes.service.js')
+const FetchPurposesService = require('../../../app/services/return-requirements/fetch-purposes.service.js')
 
 // Thing under test
 const PurposeService = require('../../../app/services/return-requirements/purpose.service.js')
@@ -26,7 +26,7 @@ describe('Return Requirements - Purpose service', () => {
   beforeEach(async () => {
     await DatabaseSupport.clean()
 
-    Sinon.stub(FetchLicencePurposesService, 'go').resolves([
+    Sinon.stub(FetchPurposesService, 'go').resolves([
       { id: '14794d57-1acf-4c91-8b48-4b1ec68bfd6f', description: 'Heat Pump' },
       { id: '49088608-ee9f-491a-8070-6831240945ac', description: 'Horticultural Watering' }
     ])

test/services/return-requirements/submit-purpose.service.test.js

@@ -12,7 +12,7 @@ const { expect } = Code
 const SessionHelper = require('../../support/helpers/session.helper.js')
 
 // Things we need to stub
-const FetchLicencePurposesService = require('../../../app/services/return-requirements/fetch-licence-purposes.service.js')
+const FetchPurposesService = require('../../../app/services/return-requirements/fetch-purposes.service.js')
 
 // Thing under test
 const SubmitPurposeService = require('../../../app/services/return-requirements/submit-purpose.service.js')
@@ -48,7 +48,7 @@ describe('Return Requirements - Submit Purpose service', () => {
 
     yarStub = { flash: Sinon.stub() }
 
-    Sinon.stub(FetchLicencePurposesService, 'go').resolves([
+    Sinon.stub(FetchPurposesService, 'go').resolves([
       { id: '14794d57-1acf-4c91-8b48-4b1ec68bfd6f', description: 'Heat Pump' },
       { id: '49088608-ee9f-491a-8070-6831240945ac', description: 'Horticultural Watering' }
     ])