feat(currency): map directive args to a currency enum

Author: thuoe

src/directives/currency.ts

@@ -1,16 +1,35 @@
 import { fetchDirective } from '@src/utils'
 import { MapperKind, mapSchema } from '@graphql-tools/utils'
 import { GraphQLError, GraphQLSchema, defaultFieldResolver } from 'graphql'
+import { CurrencyCode } from '@src/types'
 import * as cheerio from 'cheerio'
 
 type CurrencyDirectiveArgs = {
   from: string
   to: string
 }
 
+const generateGraphQLEnum = (origin: Record<string, string>) => {
+  const formattedCodes = Object.keys(origin).map((code) => {
+    return `${code} \n`
+  }).join('')
+  const result = `enum CurrencyCode {\n${formattedCodes} }`
+  return result
+}
+
+const validateCodes = (...codes: string[]) => {
+  const validCodes = Object.keys(CurrencyCode)
+  const invalidCodes = codes.filter(code => !validCodes.includes(code))
+  if (invalidCodes.length > 0) {
+    throw new GraphQLError(`Currency codes: ${invalidCodes} are not valid!`)
+  }
+}
+
 const currencyDirective = (directiveName: string = 'currency') => {
   return {
-    currencyDirectiveTypeDefs: `directive @${directiveName}(from: String!, to: String!) on FIELD_DEFINITION`,
+    currencyDirectiveTypeDefs: `directive @${directiveName} (from: String!, to: String!) on FIELD_DEFINITION
+      ${generateGraphQLEnum(CurrencyCode)}
+  `,
     currencyDirectiveTransformer: (schema: GraphQLSchema) => mapSchema(schema, {
       [MapperKind.OBJECT_FIELD]: (fieldConfig) => {
         const currencyDirective = fetchDirective<CurrencyDirectiveArgs>(schema, fieldConfig, directiveName)
@@ -20,6 +39,7 @@ const currencyDirective = (directiveName: string = 'currency') => {
           return {
             ...fieldConfig,
             resolve: async (source, args, context, info) => {
+              validateCodes(from, to)
               const { fieldName, returnType } = info
               const type = returnType.toString()
               if (type !== 'String') {

src/types.ts

@@ -0,0 +1,160 @@
+export enum CurrencyCode {
+  AED = 'AED',
+  AFN = 'AFN',
+  ALL = 'ALL',
+  AMD = 'AMD',
+  ANG = 'ANG',
+  AOA = 'AOA',
+  ARS = 'ARS',
+  AUD = 'AUD',
+  AWG = 'AWG',
+  AZN = 'AZN',
+  BAM = 'BAM',
+  BBD = 'BBD',
+  BDT = 'BDT',
+  BGN = 'BGN',
+  BHD = 'BHD',
+  BIF = 'BIF',
+  BMD = 'BMD',
+  BND = 'BND',
+  BOB = 'BOB',
+  BRL = 'BRL',
+  BSD = 'BSD',
+  BTN = 'BTN',
+  BWP = 'BWP',
+  BYN = 'BYN',
+  BZD = 'BZD',
+  CAD = 'CAD',
+  CDF = 'CDF',
+  CHF = 'CHF',
+  CLP = 'CLP',
+  CNY = 'CNY',
+  COP = 'COP',
+  CRC = 'CRC',
+  CUC = 'CUC',
+  CUP = 'CUP',
+  CVE = 'CVE',
+  CZK = 'CZK',
+  DJF = 'DJF',
+  DKK = 'DKK',
+  DOP = 'DOP',
+  DZD = 'DZD',
+  EGP = 'EGP',
+  ERN = 'ERN',
+  ETB = 'ETB',
+  EUR = 'EUR',
+  FJD = 'FJD',
+  FKP = 'FKP',
+  GBP = 'GBP',
+  GEL = 'GEL',
+  GHS = 'GHS',
+  GIP = 'GIP',
+  GMD = 'GMD',
+  GNF = 'GNF',
+  GTQ = 'GTQ',
+  GYD = 'GYD',
+  HKD = 'HKD',
+  HNL = 'HNL',
+  HRK = 'HRK',
+  HTG = 'HTG',
+  HUF = 'HUF',
+  IDR = 'IDR',
+  ILS = 'ILS',
+  INR = 'INR',
+  IQD = 'IQD',
+  IRR = 'IRR',
+  ISK = 'ISK',
+  JMD = 'JMD',
+  JOD = 'JOD',
+  JPY = 'JPY',
+  KES = 'KES',
+  KGS = 'KGS',
+  KHR = 'KHR',
+  KMF = 'KMF',
+  KPW = 'KPW',
+  KRW = 'KRW',
+  KWD = 'KWD',
+  KYD = 'KYD',
+  KZT = 'KZT',
+  LAK = 'LAK',
+  LBP = 'LBP',
+  LKR = 'LKR',
+  LRD = 'LRD',
+  LSL = 'LSL',
+  LYD = 'LYD',
+  MAD = 'MAD',
+  MDL = 'MDL',
+  MGA = 'MGA',
+  MKD = 'MKD',
+  MMK = 'MMK',
+  MNT = 'MNT',
+  MOP = 'MOP',
+  MRU = 'MRU',
+  MUR = 'MUR',
+  MVR = 'MVR',
+  MWK = 'MWK',
+  MXN = 'MXN',
+  MYR = 'MYR',
+  MZN = 'MZN',
+  NAD = 'NAD',
+  NGN = 'NGN',
+  NIO = 'NIO',
+  NOK = 'NOK',
+  NPR = 'NPR',
+  NZD = 'NZD',
+  OMR = 'OMR',
+  PAB = 'PAB',
+  PEN = 'PEN',
+  PGK = 'PGK',
+  PHP = 'PHP',
+  PKR = 'PKR',
+  PLN = 'PLN',
+  PYG = 'PYG',
+  QAR = 'QAR',
+  RON = 'RON',
+  RSD = 'RSD',
+  RUB = 'RUB',
+  RWF = 'RWF',
+  SAR = 'SAR',
+  SBD = 'SBD',
+  SCR = 'SCR',
+  SDG = 'SDG',
+  SEK = 'SEK',
+  SGD = 'SGD',
+  SHP = 'SHP',
+  SLL = 'SLL',
+  SOS = 'SOS',
+  SRD = 'SRD',
+  SSP = 'SSP',
+  STN = 'STN',
+  SVC = 'SVC',
+  SYP = 'SYP',
+  SZL = 'SZL',
+  THB = 'THB',
+  TJS = 'TJS',
+  TMT = 'TMT',
+  TND = 'TND',
+  TOP = 'TOP',
+  TRY = 'TRY',
+  TTD = 'TTD',
+  TWD = 'TWD',
+  TZS = 'TZS',
+  UAH = 'UAH',
+  UGX = 'UGX',
+  USD = 'USD',
+  UYU = 'UYU',
+  UZS = 'UZS',
+  VES = 'VES',
+  VND = 'VND',
+  VUV = 'VUV',
+  WST = 'WST',
+  XAF = 'XAF',
+  XCD = 'XCD',
+  XOF = 'XOF',
+  XPF = 'XPF',
+  YER = 'YER',
+  ZAR = 'ZAR',
+  ZMW = 'ZMW',
+  ZWL = 'ZWL',
+}
+

test/currency.test.ts

@@ -63,7 +63,39 @@ describe('@currency directive', () => {
     expect(fetchSpy).toHaveBeenCalled()
     expect(fetchSpy).toHaveBeenCalledWith(`https://www.google.com/search?q=${amount}+${from}+to+${to}+&hl=en`)
   })
+
   it.todo('will convert from one currency to another and return a integer')
   it.todo('will convert from one currency to another and format with a seperator')
-  it.todo('will throw an error if currency code is not recognized')
+
+  it('will throw an error if currency code(s) are not recognized', async () => {
+    const fetchSpy = jest.spyOn(global, 'fetch')
+    const from = 'BLAH'
+    const to = 'HMMMM'
+    const schema = buildSchema({
+      typeDefs: [
+        `type User {
+          amount: String @currency(from: "${from}", to: "${to}")
+        }
+
+        type Query {
+          user: User
+        }
+        `,
+        currencyDirectiveTypeDefs
+      ],
+      resolvers,
+      transformers: [currencyDirectiveTransformer]
+    })
+
+    testServer = new ApolloServer({ schema })
+
+    const response = await testServer.executeOperation<{ user: { amount: string } }>({
+      query: testQuery
+    })
+
+    assert(response.body.kind === 'single')
+    expect(response.body.singleResult.errors).toBeDefined();
+    expect(response.body.singleResult.errors[0].message).toBe(`Currency codes: ${from},${to} are not valid!`);
+    expect(fetchSpy).not.toHaveBeenCalled()
+  })
 })