refactor: convert CsvMergedHeadersGenerator to typescript (#2080)

* refactor: convert response classes to typescript and change response to abstract class

* refactor: rearrange types

* refactor: convert CsvMergedHeadersGenerator to typescript

* refactor: edit export and import statements for CsvMergedHeadersGenerator

* fix: edit import statement of  generator in submissions.client.factory

* refactor: edit response types

* refactor: remove typing in jsdocs and edit types

* refactor: export response subclasses input types

* refactor: add ErrorResponse as default for response types

* refactor: shift hasProps to shared

* refactor: athrow error instead of returning ErrorResponse and edited typeguards

* refactor: change interface to type

* fix: fix incorrect import statement

* test: remove single header row test

* fix: fix bug caused by fieldtype guard and if else condition

* refactor: remove console.log

* refactor: convert extractAnswer to private function

* docs: add jsdocs for response factory

* docs: edit jsdocs for addRecord

* refactor: extract acheck for answer array

* refactor: revert extractAnswer to non-private function

* refactor: remove repeated check for type Array

* refactor: create SubmissionRecord type

* refactor: rename ccsv generator in submissions client factory

* refactor: make _data field private

* test: rrestore deleted test and edit expected unprocessed record

* test: remove repeated test

* refactor: use private modifier in typescript classes

* test: add tests for error cases

* refactor: add private modifier to date comparator

* refactor: remove underscore from private field

* refactor: extract type in csvmhgenerator

* refactor: replace strings with basic field enums

* fix: fix import statement

src/app/modules/bounce/bounce.service.ts

@@ -10,6 +10,7 @@ import {
   ResultAsync,
 } from 'neverthrow'
 
+import { hasProp } from '../../../shared/util/has-prop'
 import {
   BounceType,
   IBounceSchema,
@@ -25,7 +26,6 @@ import { EMAIL_HEADERS, EmailType } from '../../services/mail/mail.constants'
 import MailService from '../../services/mail/mail.service'
 import { SmsFactory } from '../../services/sms/sms.factory'
 import { transformMongoError } from '../../utils/handle-mongo-error'
-import { hasProp } from '../../utils/has-prop'
 import { PossibleDatabaseError } from '../core/core.errors'
 import { getCollabEmailsWithPermission } from '../form/form.utils'
 import * as UserService from '../user/user.service'

src/app/modules/myinfo/myinfo.util.ts

@@ -6,6 +6,7 @@ import { err, ok, Result } from 'neverthrow'
 import { v4 as uuidv4, validate as validateUUID } from 'uuid'
 
 import { types as myInfoTypes } from '../../../shared/resources/myinfo'
+import { hasProp } from '../../../shared/util/has-prop'
 import {
   AuthType,
   BasicField,
@@ -16,7 +17,6 @@ import {
   MapRouteError,
 } from '../../../types'
 import { createLoggerWithLabel } from '../../config/logger'
-import { hasProp } from '../../utils/has-prop'
 import { DatabaseError, MissingFeatureError } from '../core/core.errors'
 import {
   AuthTypeMismatchError,

src/app/modules/spcp/spcp.util.ts

@@ -3,6 +3,7 @@ import crypto from 'crypto'
 import { StatusCodes } from 'http-status-codes'
 import { err, ok, Result } from 'neverthrow'
 
+import { hasProp } from '../../../shared/util/has-prop'
 import {
   AuthType,
   BasicField,
@@ -11,7 +12,6 @@ import {
   SPCPFieldTitle,
 } from '../../../types'
 import { createLoggerWithLabel } from '../../config/logger'
-import { hasProp } from '../../utils/has-prop'
 import { MissingFeatureError } from '../core/core.errors'
 import {
   AuthTypeMismatchError,

src/public/modules/forms/helpers/CsvMergedHeadersGenerator.js → src/public/modules/forms/helpers/CsvMergedHeadersGenerator.ts

@@ -1,21 +1,40 @@
-const moment = require('moment-timezone')
-const keyBy = require('lodash/keyBy')
-const { CsvGenerator } = require('./CsvGenerator')
-const { getResponseInstance } = require('./response-factory')
-
-/**
- * @typedef {{
- *    _id: string,
- *    question: string,
- *    answer?: string,
- *    answerArray?: string[],
- *    fieldType: string,
- *    isHeader?: boolean,
- * }} DisplayedResponse
- */
-
-class CsvMergedHeadersGenerator extends CsvGenerator {
-  constructor(expectedNumberOfRecords, numOfMetaDataRows) {
+import keyBy from 'lodash/keyBy'
+import moment from 'moment-timezone'
+
+import { DisplayedResponseWithoutAnswer } from '../../../../types/response'
+
+import { Response } from './csv-response-classes'
+import { CsvGenerator } from './CsvGenerator'
+import { getResponseInstance } from './response-factory'
+
+type KeyedResponse = { [fieldId: string]: Response }
+
+type UnprocessedRecord = {
+  created: string
+  submissionId: string
+  record: KeyedResponse
+}
+
+type SubmissionRecord = {
+  record: DisplayedResponseWithoutAnswer[]
+  created: string
+  submissionId: string
+}
+
+export class CsvMergedHeadersGenerator extends CsvGenerator {
+  hasBeenProcessed: boolean
+  hasBeenSorted: boolean
+  fieldIdToQuestion: Map<
+    string,
+    {
+      created: string
+      question: string
+    }
+  >
+  fieldIdToNumCols: Record<string, number>
+  unprocessed: UnprocessedRecord[]
+
+  constructor(expectedNumberOfRecords: number, numOfMetaDataRows: number) {
     super(expectedNumberOfRecords, numOfMetaDataRows)
 
     this.hasBeenProcessed = false
@@ -28,25 +47,25 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
   /**
    * Returns current length of CSV file excluding header and meta-data
    */
-  length() {
+  length(): number {
     return this.unprocessed.length
   }
 
   /**
-   *
-   * @param {Object} decryptedContent
-   * @param {DisplayedResponse[]} decryptedContent.record
-   * @param {string} decryptedContent.created
-   * @param {string} decryptedContent.submissionId
+   * Extracts information from input record, rearranges record and then adds an UnprocessedRecord to this.unprocessed
+   * @param decryptedContent
+   * @param decryptedContent.record
+   * @param decryptedContent.created
+   * @param decryptedContent.submissionId
+   * @throws Error when trying to convert record into a response instance. Should be caught in submissions client factory.
    */
-  addRecord({ record, created, submissionId }) {
+  addRecord({ record, created, submissionId }: SubmissionRecord): void {
     // First pass, create object with { [fieldId]: question } from
     // decryptedContent to get all the questions.
     const fieldRecords = record.map((content) => {
       const fieldRecord = getResponseInstance(content)
       if (!fieldRecord.isHeader) {
         const currentMapping = this.fieldIdToQuestion.get(fieldRecord.id)
-
         // Only set new mapping if it does not exist or this record is a later
         // submission.
         // Might need to differentiate the question headers if we allow
@@ -77,28 +96,16 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
     })
   }
 
-  /**
-   * Extracts the string representation from an unprocessed record.
-   * @param {Object} unprocessedRecord
-   * @param {string} fieldId
-   * @returns {string}
-   */
-  _extractAnswer(unprocessedRecord, fieldId, colIndex) {
-    const fieldRecord = unprocessedRecord[fieldId]
-    if (!fieldRecord) return ''
-    return fieldRecord.getAnswer(colIndex)
-  }
-
   /**
    * Process the unprocessed records by creating the correct headers and
    * assigning each answer to their respective locations in each response row in
    * the csv data.
    */
-  process() {
+  process(): void {
     if (this.hasBeenProcessed) return
 
     // Create a header row in CSV using the fieldIdToQuestion map.
-    let headers = ['Reference number', 'Timestamp']
+    const headers = ['Reference number', 'Timestamp']
     this.fieldIdToQuestion.forEach((value, fieldId) => {
       for (let i = 0; i < this.fieldIdToNumCols[fieldId]; i++) {
         headers.push(value.question)
@@ -109,26 +116,44 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
     // Craft a new csv row for each unprocessed record
     // O(qn), where q = number of unique questions, n = number of submissions.
     this.unprocessed.forEach((up) => {
-      let createdAt = moment(up.created).tz('Asia/Singapore')
-      createdAt = createdAt.isValid()
+      const createdAt = moment(up.created).tz('Asia/Singapore')
+      const formattedDate = createdAt.isValid()
         ? createdAt.format('DD MMM YYYY hh:mm:ss A')
-        : createdAt
-      let row = [up.submissionId, createdAt]
-      for (let [fieldId] of this.fieldIdToQuestion) {
+        : createdAt.toString() // just convert to string if given date is not valid
+      const row = [up.submissionId, formattedDate]
+
+      this.fieldIdToQuestion.forEach((_question, fieldId) => {
         const numCols = this.fieldIdToNumCols[fieldId]
         for (let colIndex = 0; colIndex < numCols; colIndex++) {
           row.push(this._extractAnswer(up.record, fieldId, colIndex))
         }
-      }
+      })
       this.addLine(row)
     })
     this.hasBeenProcessed = true
   }
 
+  /**
+   * Extracts the string representation from a field response
+   * @param unprocessedRecord
+   * @param fieldId
+   * @param colIndex
+   * @returns string representation of unprocessed record
+   */
+  private _extractAnswer(
+    unprocessedRecord: KeyedResponse,
+    fieldId: string,
+    colIndex: number,
+  ): string {
+    const fieldRecord = unprocessedRecord[fieldId]
+    if (!fieldRecord) return ''
+    return fieldRecord.getAnswer(colIndex)
+  }
+
   /**
    * Sorts unprocessed records from oldest to newest
    */
-  sort() {
+  sort(): void {
     if (this.hasBeenSorted) return
     this.unprocessed.sort((a, b) => this._dateComparator(a.created, b.created))
     this.hasBeenSorted = true
@@ -138,8 +163,8 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
    * Add meta-data as first three rows of the CSV. If there is already meta-data
    * added, it will be replaced by the latest counts.
    */
-  addMetaDataFromSubmission(errorCount, unverifiedCount) {
-    let metaDataRows = [
+  addMetaDataFromSubmission(errorCount: number, unverifiedCount: number): void {
+    const metaDataRows = [
       ['Expected total responses', this.expectedNumberOfRecords],
       ['Success count', this.length()],
       ['Error count', errorCount],
@@ -151,20 +176,20 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
 
   /**
    * Main method to call to retrieve a downloadable csv.
-   * @param {string} filename
+   * @param filename name of csv file
    */
-  downloadCsv(filename) {
+  downloadCsv(filename: string): void {
     this.sort()
     this.process()
     this.triggerFileDownload(filename)
   }
 
   /**
    * Comparator for dates
-   * @param string firstDate
-   * @param string secondDate
+   * @param firstDate
+   * @param secondDate
    */
-  _dateComparator(firstDate, secondDate) {
+  private _dateComparator(firstDate: string, secondDate: string): number {
     // cast to Asia/Singapore to ensure both dates are of the same timezone
     const first = moment(firstDate).tz('Asia/Singapore')
     const second = moment(secondDate).tz('Asia/Singapore')
@@ -178,5 +203,3 @@ class CsvMergedHeadersGenerator extends CsvGenerator {
     }
   }
 }
-
-module.exports = CsvMergedHeadersGenerator

src/public/modules/forms/helpers/csv-response-classes/ArrayAnswerResponse.class.ts

@@ -0,0 +1,20 @@
+import { ArrayResponse } from '../../../../../types/response'
+
+import { Response } from './Response.class'
+
+export class ArrayAnswerResponse extends Response {
+  private response: ArrayResponse
+
+  constructor(responseData: ArrayResponse) {
+    super(responseData)
+    this.response = responseData
+  }
+
+  getAnswer(): string {
+    return this.response.answerArray.join(';')
+  }
+
+  get numCols(): number {
+    return 1
+  }
+}

src/public/modules/forms/helpers/csv-response-classes/Response.class.ts

@@ -0,0 +1,29 @@
+import { DisplayedResponseWithoutAnswer } from '../../../../../types/response'
+
+export abstract class Response {
+  private data: DisplayedResponseWithoutAnswer
+
+  constructor(responseData: DisplayedResponseWithoutAnswer) {
+    this.data = responseData
+  }
+
+  get id(): string {
+    return this.data._id
+  }
+
+  /**
+   * Gets the CSV header.
+   * @returns {string}
+   */
+  get question(): string {
+    return this.data.question
+  }
+
+  get isHeader(): boolean {
+    return this.data.isHeader ?? false
+  }
+
+  abstract get numCols(): number
+
+  abstract getAnswer(colIndex?: number): string
+}

src/public/modules/forms/helpers/csv-response-classes/SingleAnswerResponse.class.ts

@@ -0,0 +1,20 @@
+import { SingleResponse } from '../../../../../types/response'
+
+import { Response } from './Response.class'
+
+export class SingleAnswerResponse extends Response {
+  private response: SingleResponse
+
+  constructor(responseData: SingleResponse) {
+    super(responseData)
+    this.response = responseData
+  }
+
+  getAnswer(): string {
+    return this.response.answer
+  }
+
+  get numCols(): number {
+    return 1
+  }
+}