Added IsFirstLetterUppercase decorator

Author: WISNIOM

apps/car-rental-backend/src/main.ts

@@ -1,4 +1,4 @@
-import { Logger } from '@nestjs/common';
+import { Logger, ValidationPipe } from '@nestjs/common';
 import { NestFactory } from '@nestjs/core';
 import { SwaggerModule, DocumentBuilder } from '@nestjs/swagger';
 import { AppModule } from './app/app.module';
@@ -8,6 +8,7 @@ async function bootstrap() {
   const config = new DocumentBuilder().setTitle('Car Rental API').build();
   const documentFactory = () => SwaggerModule.createDocument(app, config);
   const globalPrefix = 'api';
+  app.useGlobalPipes(new ValidationPipe());
   app.setGlobalPrefix(globalPrefix);
   const port = process.env.PORT || 3000;
   SwaggerModule.setup('api', app, documentFactory);

apps/car-rental-backend/src/validators/is-first-letter-uppercase.decorator.ts

@@ -0,0 +1,32 @@
+import {
+    registerDecorator,
+  ValidationOptions,
+  ValidatorConstraint,
+  ValidatorConstraintInterface,
+} from 'class-validator';
+
+@ValidatorConstraint({ name: 'isFirstLetterUppercase', async: false })
+export class IsFirstLetterUppercaseConstraint
+  implements ValidatorConstraintInterface
+{
+  validate(text: string) {
+    return /^[A-Z]/.test(text);
+  }
+
+  defaultMessage() {
+    return 'The first letter of the text must be uppercase';
+  }
+}
+
+
+export function IsFirstLetterUppercase(validationOptions?: ValidationOptions) {
+  return function (object: object, propertyName: string) {
+    registerDecorator({
+      target: object.constructor,
+      propertyName: propertyName,
+      options: validationOptions,
+      constraints: [],
+      validator: IsFirstLetterUppercaseConstraint,
+    });
+  };
+}

apps/car-rental-backend/src/vehicle-brands/dto/create-vehicle-brand.dto.ts

@@ -1,6 +1,14 @@
-import { ApiProperty } from "@nestjs/swagger";
-
+import { ApiProperty } from '@nestjs/swagger';
+import { IsString, Length } from 'class-validator';
+import { IsFirstLetterUppercase } from '../../validators/is-first-letter-uppercase.decorator';
 export class CreateVehicleBrandDto {
-    @ApiProperty({ example: 'Toyota', description: 'The name of the vehicle brand', type: 'string' })
-    name: string;
+  @IsString()
+  @Length(1, 50)
+  @IsFirstLetterUppercase()
+  @ApiProperty({
+    example: 'Toyota',
+    description: 'The name of the vehicle brand. The first character must be uppercase. Allowed length is 1-50 characters.',
+    type: 'string',
+  })
+  name: string;
 }