Merge pull request #675 from DEFRA/feature/services-strategy-pattern

Feature/services strategy pattern

src/server/plugins/engine/configureEnginePlugin.ts

@@ -12,20 +12,21 @@ import { type RouteConfig } from '~/src/server/types.js'
 
 export const configureEnginePlugin = async ({
   formFileName,
-  formFilePath
+  formFilePath,
+  services
 }: RouteConfig = {}): Promise<ServerRegisterPluginObject<PluginOptions>> => {
   let model: FormModel | undefined
 
   if (formFileName && formFilePath) {
     const definition = await getForm(join(formFilePath, formFileName))
     const { name } = parse(formFileName)
 
-    model = new FormModel(definition, { basePath: name })
+    model = new FormModel(definition, { basePath: name }, services)
   }
 
   return {
     plugin,
-    options: { model }
+    options: { model, services }
   }
 }
 

src/server/plugins/engine/models/FormModel.ts

@@ -26,6 +26,7 @@ import {
   type PageControllerClass
 } from '~/src/server/plugins/engine/pageControllers/helpers.js'
 import { validationOptions as opts } from '~/src/server/plugins/engine/pageControllers/validationOptions.js'
+import * as defaultServices from '~/src/server/plugins/engine/services/index.js'
 import {
   type FormContext,
   type FormContextRequest,
@@ -34,10 +35,8 @@ import {
 } from '~/src/server/plugins/engine/types.js'
 import { FormAction } from '~/src/server/routes/types.js'
 import { merge } from '~/src/server/services/cacheService.js'
+import { type Services } from '~/src/server/types.js'
 
-/**
- * Responsible for instantiating the {@link PageControllerClass} and condition context from a form JSON
- */
 export class FormModel {
   /** The runtime engine that should be used */
   engine?: Engine
@@ -52,8 +51,13 @@ export class FormModel {
   basePath: string
   conditions: Partial<Record<string, ExecutableCondition>>
   pages: PageControllerClass[]
+  services: Services
 
-  constructor(def: typeof this.def, options: { basePath: string }) {
+  constructor(
+    def: typeof this.def,
+    options: { basePath: string },
+    services: Services = defaultServices
+  ) {
     const result = formDefinitionSchema.validate(def, { abortEarly: false })
 
     if (result.error) {
@@ -89,6 +93,7 @@ export class FormModel {
     this.values = result.value
     this.basePath = options.basePath
     this.conditions = {}
+    this.services = services
 
     def.conditions.forEach((conditionDef) => {
       const condition = this.makeCondition(conditionDef)

src/server/plugins/engine/pageControllers/QuestionPageController.ts

@@ -21,7 +21,6 @@ import {
 } from '~/src/server/plugins/engine/helpers.js'
 import { type FormModel } from '~/src/server/plugins/engine/models/index.js'
 import { PageController } from '~/src/server/plugins/engine/pageControllers/PageController.js'
-import { getFormMetadata } from '~/src/server/plugins/engine/services/formsService.js'
 import {
   type FormContext,
   type FormContextRequest,
@@ -398,6 +397,8 @@ export class QuestionPageController extends PageController {
 
     const startPath = this.getStartPath()
     const summaryPath = this.getSummaryPath()
+    const { formsService } = this.model.services
+    const { getFormMetadata } = formsService
 
     // Warn the user if the form has no notification email set only on start page and summary page
     if ([startPath, summaryPath].includes(path) && !isForceAccess) {

src/server/plugins/engine/pageControllers/StatusPageController.ts

@@ -3,7 +3,6 @@ import { type ResponseToolkit } from '@hapi/hapi'
 
 import { type FormModel } from '~/src/server/plugins/engine/models/index.js'
 import { QuestionPageController } from '~/src/server/plugins/engine/pageControllers/QuestionPageController.js'
-import { getFormMetadata } from '~/src/server/plugins/engine/services/formsService.js'
 import { type FormContext } from '~/src/server/plugins/engine/types.js'
 import { type FormRequest } from '~/src/server/routes/types.js'
 
@@ -37,6 +36,9 @@ export class StatusPageController extends QuestionPageController {
       }
 
       const slug = request.params.slug
+      const { formsService } = this.model.services
+      const { getFormMetadata } = formsService
+
       const { submissionGuidance } = await getFormMetadata(slug)
 
       return h.view(viewName, {

src/server/plugins/engine/pageControllers/SummaryPageController.ts

@@ -26,11 +26,6 @@ import {
   type DetailItem
 } from '~/src/server/plugins/engine/models/types.js'
 import { QuestionPageController } from '~/src/server/plugins/engine/pageControllers/QuestionPageController.js'
-import {
-  persistFiles,
-  submit
-} from '~/src/server/plugins/engine/services/formSubmissionService.js'
-import { getFormMetadata } from '~/src/server/plugins/engine/services/formsService.js'
 import {
   type FormContext,
   type FormContextRequest,
@@ -108,6 +103,8 @@ export class SummaryPageController extends QuestionPageController {
       const { state } = context
 
       const { cacheService } = request.services([])
+      const { formsService } = this.model.services
+      const { getFormMetadata } = formsService
 
       // Get the form metadata using the `slug` param
       const { notificationEmail } = await getFormMetadata(params.slug)
@@ -160,6 +157,8 @@ async function extendFileRetention(
   state: FormSubmissionState,
   updatedRetrievalKey: string
 ) {
+  const { formSubmissionService } = model.services
+  const { persistFiles } = formSubmissionService
   const files: { fileId: string; initiatedRetrievalKey: string }[] = []
 
   // For each file upload component with files in
@@ -190,10 +189,14 @@ async function extendFileRetention(
 }
 
 function submitData(
+  model: FormModel,
   items: DetailItem[],
   retrievalKey: string,
   sessionId: string
 ) {
+  const { formSubmissionService } = model.services
+  const { submit } = formSubmissionService
+
   const payload: SubmitPayload = {
     sessionId,
     retrievalKey,
@@ -248,7 +251,12 @@ async function sendEmail(
 
   // Submit data
   request.logger.info(logTags, 'Submitting data')
-  const submitResponse = await submitData(items, emailAddress, request.yar.id)
+  const submitResponse = await submitData(
+    model,
+    items,
+    emailAddress,
+    request.yar.id
+  )
 
   if (submitResponse === undefined) {
     throw Boom.badRequest('Unexpected empty response from submit api')

src/server/plugins/engine/plugin.ts

@@ -24,10 +24,7 @@ import { FormModel } from '~/src/server/plugins/engine/models/index.js'
 import { FileUploadPageController } from '~/src/server/plugins/engine/pageControllers/FileUploadPageController.js'
 import { RepeatPageController } from '~/src/server/plugins/engine/pageControllers/RepeatPageController.js'
 import { type PageControllerClass } from '~/src/server/plugins/engine/pageControllers/helpers.js'
-import {
-  getFormDefinition,
-  getFormMetadata
-} from '~/src/server/plugins/engine/services/formsService.js'
+import * as defaultServices from '~/src/server/plugins/engine/services/index.js'
 import { type FormContext } from '~/src/server/plugins/engine/types.js'
 import {
   type FormRequest,
@@ -43,17 +40,20 @@ import {
   pathSchema,
   stateSchema
 } from '~/src/server/schemas/index.js'
+import { type Services } from '~/src/server/types.js'
 
 export interface PluginOptions {
   model?: FormModel
+  services?: Services
 }
 
 export const plugin = {
   name: '@defra/forms-runner/engine',
   dependencies: '@hapi/vision',
   multiple: true,
   register(server, options) {
-    const { model } = options
+    const { model, services = defaultServices } = options
+    const { formsService } = services
 
     server.app.model = model
 
@@ -77,7 +77,7 @@ export const plugin = {
       const { isPreview, state: formState } = checkFormStatus(path)
 
       // Get the form metadata using the `slug` param
-      const metadata = await getFormMetadata(slug)
+      const metadata = await formsService.getFormMetadata(slug)
 
       const { id, [formState]: state } = metadata
 
@@ -101,7 +101,7 @@ export const plugin = {
         )
 
         // Get the form definition using the `id` from the metadata
-        const definition = await getFormDefinition(id, formState)
+        const definition = await formsService.getFormDefinition(id, formState)
 
         if (!definition) {
           throw Boom.notFound(
@@ -125,7 +125,7 @@ export const plugin = {
           : slug
 
         // Construct the form model
-        const model = new FormModel(definition, { basePath })
+        const model = new FormModel(definition, { basePath }, services)
 
         // Create new item and add it to the item cache
         item = { model, updatedAt: state.updatedAt }

src/server/plugins/engine/services/formSubmissionService.js

@@ -9,7 +9,7 @@ const submissionUrl = config.get('submissionUrl')
  * @param {string} persistedRetrievalKey - final retrieval key when submitting
  */
 export async function persistFiles(files, persistedRetrievalKey) {
-  const postJsonByType = /** @type {typeof postJson} */ (postJson)
+  const postJsonByType = /** @type {typeof postJson<object>} */ (postJson)
 
   const payload = {
     files,

src/server/plugins/engine/services/index.js

@@ -0,0 +1,2 @@
+export * as formsService from '~/src/server/plugins/engine/services/formsService.js'
+export * as formSubmissionService from '~/src/server/plugins/engine/services/formSubmissionService.js'

src/server/types.ts

@@ -1,5 +1,36 @@
+import {
+  type FormDefinition,
+  type FormMetadata,
+  type SubmitPayload,
+  type SubmitResponsePayload
+} from '@defra/forms-model'
+
+import { type FormStatus } from '~/src/server/routes/types.js'
+
+export interface FormsService {
+  getFormMetadata: (slug: string) => Promise<FormMetadata>
+  getFormDefinition: (
+    id: string,
+    state: FormStatus
+  ) => Promise<FormDefinition | undefined>
+}
+
+export interface FormSubmissionService {
+  persistFiles: (
+    files: { fileId: string; initiatedRetrievalKey: string }[],
+    persistedRetrievalKey: string
+  ) => Promise<object>
+  submit: (data: SubmitPayload) => Promise<SubmitResponsePayload | undefined>
+}
+
+export interface Services {
+  formsService: FormsService
+  formSubmissionService: FormSubmissionService
+}
+
 export interface RouteConfig {
   formFileName?: string
   formFilePath?: string
   enforceCsrf?: boolean
+  services?: Services
 }