feature: translate validation keys, related to #355

package.json

@@ -21,6 +21,7 @@
     "format": "prettier --write \"src/**/*.ts\" \"tests/**/*.ts\"",
     "test": "jest --config ./tests/jest-test.json",
     "test:cov": "jest --config ./tests/jest-test.json --coverage",
+    "test:watch": "jest --config ./tests/jest-test.json --watch",
     "coveralls": "npm run test:cov && cat ./coverage/lcov.info | coveralls",
     "lint": "eslint . --ext .ts",
     "lint:fix": "eslint . --ext .ts --fix",
@@ -111,4 +112,4 @@
       "last 1 safari version"
     ]
   }
-}
+}

src/filters/i18n-validation-exception.filter.ts

@@ -63,12 +63,34 @@ export class I18nValidationExceptionFilter implements ExceptionFilter {
       error.children = this.translateErrors(error.children ?? [], i18n);
       error.constraints = Object.keys(error.constraints).reduce(
         (result, key) => {
+          // separate translation key and args
           const [translationKey, argsString] =
             error.constraints[key].split('|');
+
+          // jsonify args
           const args = !!argsString ? JSON.parse(argsString) : {};
+
           result[key] = i18n.t(translationKey, {
             args: { property: error.property, ...args },
           });
+
+          // replace error.property with translated property
+          const errorPropertyInString = (result[key] as string).match(
+            error.property,
+          );
+          let replacementKey = error.property;
+          if (errorPropertyInString) {
+            const baseKey = translationKey.split('.')[0];
+            const replacementKeySub = i18n.t(
+              baseKey + '.' + errorPropertyInString[0],
+            ) as string;
+            if (!replacementKeySub.includes(baseKey)) {
+              replacementKey = replacementKeySub;
+            }
+          }
+
+          result[key] = result[key].replace(error.property, replacementKey);
+
           return result;
         },
         {},

src/i18n.context.ts

@@ -1,7 +1,7 @@
 import { I18nService, TranslateOptions } from './services/i18n.service';
 
 export class I18nContext {
-  constructor(readonly lang: string, private readonly service: I18nService) {}
+  constructor(readonly lang: string, private readonly service: I18nService) { }
 
   public translate<T = any>(key: string, options?: TranslateOptions): T {
     options = {

src/services/i18n.service.ts

@@ -173,7 +173,6 @@ export class I18nService {
       const pluralObject = this.getPluralObject(translation);
       if (pluralObject && args && args['count'] !== undefined) {
         const count = Number(args['count']);
-
         if (count == 0 && !!pluralObject.zero) {
           translation = pluralObject.zero;
         } else if (count == 1 && !!pluralObject.one) {

tests/app/controllers/hello.controller.ts

@@ -29,7 +29,7 @@ export class HelloController {
   constructor(
     private i18n: I18nService,
     private i18nRequestScope: I18nRequestScopeService,
-  ) {}
+  ) { }
 
   @Get()
   hello(@I18nLang() lang: string): any {
@@ -49,7 +49,7 @@ export class HelloController {
 
   @Get('/index2')
   @Render('index2')
-  index2(): any {}
+  index2(): any { }
 
   @Get('/short')
   helloShort(@I18nLang() lang: string): any {
@@ -162,6 +162,12 @@ export class HelloController {
     return 'This action adds a new user';
   }
 
+  @Post('/validation-with-keys')
+  @UseFilters(new I18nValidationExceptionFilter({ detailedErrors: false }))
+  validationWithKeys(@Body() createUserDto: CreateUserDto): any {
+    return 'This action adds a new user';
+  }
+
   @Post('/validation-with-custom-http-code')
   @UseFilters(new I18nValidationExceptionFilter({ errorHttpStatusCode: 422 }))
   validationWithCustomHttpCode(@Body() createUserDto: CreateUserDto): any {
@@ -178,6 +184,8 @@ export class HelloController {
     return 'This action adds a new user';
   }
 
+
+
   @GrpcMethod('HeroesService', 'FindOne')
   findOne(@Payload() data: HeroById, @I18n() i18n: I18nContext): Hero {
     const items = [

tests/i18n-dto.e2e.spec.ts

@@ -96,6 +96,21 @@ describe('i18n module e2e dto', () => {
     ],
   };
 
+  it('should return translation of keys too', async () => {
+    const response = await request(app.getHttpServer())
+      .post('/hello/validation-with-keys')
+      .set('x-custom-lang', 'fa')
+      .set('Accept', 'application/json')
+      .send({
+        email: '',
+        password: '',
+        extra: { subscribeToEmail: true, min: 1, max: 100 },
+      });
+
+    expect(response.status).toBe(400);
+    expect(response.body.errors[1]).toEqual("ایمیل نباید خالی باشد");
+  })
+
   it(`should translate validation messages in a custom format if specified`, async () => {
     await request(app.getHttpServer())
       .post('/hello/validation-custom-formatter')
@@ -167,7 +182,7 @@ describe('i18n module e2e dto', () => {
           statusCode: 400,
           message: 'Bad Request',
           errors: {
-            email: ['email is ongeldig', 'e-mail adres mag niet leeg zijn'],
+            email: ['e-mail adres is ongeldig', 'e-mail adres mag niet leeg zijn'],
             password: ['wachtwoord mag niet leeg zijn'],
             subscribeToEmail: ['extra.subscribeToEmail is geen boolean'],
             min: [
@@ -246,7 +261,7 @@ describe('i18n module e2e dto', () => {
           statusCode: 400,
           message: 'Bad Request',
           errors: [
-            'email is ongeldig',
+            'e-mail adres is ongeldig',
             'e-mail adres mag niet leeg zijn',
             'wachtwoord mag niet leeg zijn',
             'extra.subscribeToEmail is geen boolean',
@@ -397,7 +412,7 @@ describe('i18n module e2e dto', () => {
               property: 'email',
               children: [],
               constraints: {
-                isEmail: 'email is ongeldig',
+                isEmail: 'e-mail adres is ongeldig',
                 isNotEmpty: 'e-mail adres mag niet leeg zijn',
               },
             },

tests/i18n.spec.ts

@@ -94,6 +94,7 @@ describe('i18n module', () => {
   it('i18n service should return supported languages', () => {
     expect(i18nService.getSupportedLanguages()).toEqual([
       'en',
+      'fa',
       'fr',
       'nl',
       'pt-BR',
@@ -365,6 +366,7 @@ describe('i18n module with fallbacks', () => {
             'en-*': 'en',
             'fr-*': 'fr',
             pt: 'pt-BR',
+            'fa': 'fa',
           },
           loaderOptions: {
             path: path.join(__dirname, '/i18n'),
@@ -386,6 +388,7 @@ describe('i18n module with fallbacks', () => {
     expect(i18nService.translate('test.HELLO', { lang: 'en-US' })).toBe(
       'Hello',
     );
+    expect(i18nService.translate('test.HELLO', { lang: 'fa' })).toBe('سلام');
   });
 
   it('i18n service should return dutch translation', () => {
@@ -407,6 +410,10 @@ describe('i18n module with fallbacks', () => {
     expect(i18nService.translate('test.HELLO', { lang: 'pt-BR' })).toBe('Olá');
   });
 
+  it('i18n service should return farsi translation', () => {
+    expect(i18nService.translate('test.HELLO', { lang: 'fa' })).toBe('سلام');
+  });
+
   it('i18n service should return translation with . in key', () => {
     expect(i18nService.translate('test.dot.test')).toBe('test');
   });

tests/i18n/fa/test.json

@@ -0,0 +1,31 @@
+{
+    "HELLO": "سلام",
+    "PRODUCT": {
+      "NEW": "New Product: {name}"
+    },
+    "ENGLISH": "English",
+    "ARRAY": ["ONE", "TWO", "THREE"],
+    "cat": "Cat",
+    "ONLY_EN_KEY": "this key only exists in en lang",
+    "cat_name": "Cat: {name}",
+    "set-up-password": {
+      "heading": "Hello, {username}",
+      "title": "Forgot password",
+      "followLink": "Please follow the link to set up your password"
+    },
+    "dot.test": "test",
+    "day_interval": {
+      "one": "Every day",
+      "other": "Every {count} days",
+      "zero": "Never"
+    },
+    "nested": "Message: $t(test.set-up-password.heading, {{\"username\":  \"{username}\" }})",
+    "nested-no-args": "We go shopping: $t(test.dot.test)",
+    "nest1": {
+      "nest2": {
+        "nest3": "We go shopping: $t(test.day_interval, {{\"count\": {count} }})"
+      }
+    },
+    "CURRENT_LANGUAGE": "Current language: {lang}"
+  }
+

tests/i18n/fa/validation-key.json

@@ -0,0 +1,4 @@
+{
+    "email": "ایمیل",
+    "password": "رمز عبور"
+}

tests/i18n/fa/validation.json

@@ -0,0 +1,9 @@
+{
+    "email": "ایمیل",
+    "password": "رمز عبور",
+    "NOT_EMPTY": "{property} نباید خالی باشد",
+    "INVALID_EMAIL": "ایمیل نامعتبر است",
+    "INVALID_BOOLEAN": "{property} باید بله یا خیر باشد",
+    "MIN": "{property} با مقادیر: \"{value}\" باید کمتر از {constraints.0}, یا {message}",
+    "MAX": "{property} با مقادیر: \"{value}\" باید کمتر از {constraints.0}, یا {message}"
+}