IMPLEMENTATION_SUMMARY.md

targetPlatforms Validation Implementation

Issue Description

targetPlatforms JSON field accepted any input, causing potential downstream posting failures.

Solution Implemented

✅ Acceptance Criteria Met

1. Custom Validator @IsValidPlatforms()

   • Created in src/videos/validators/is-valid-platforms.validator.ts
   • Validates array of supported platforms
   • Provides detailed error messages

2. Supported Platforms

   • tiktok
   • instagram
   • youtube-shorts
   • youtube
   • facebook
   • twitter
   • snapchat

3. Automatic Normalization

   • Converts to lowercase using @Transform decorator
   • Deduplicates using Set
   • Applied in both CreateVideoDto and UpdateVideoDto

4. Returns 400 on Invalid Values

   • Validation integrated with class-validator
   • NestJS automatically returns 400 Bad Request
   • Includes detailed error messages listing invalid platforms

Files Created

Core Implementation

• src/videos/validators/is-valid-platforms.validator.ts - Validator constraint
• src/videos/validators/decorators.ts - @IsValidPlatforms() decorator
• src/videos/dto/create-video.dto.ts - Create video DTO with validation
• src/videos/dto/update-video.dto.ts - Update video DTO with validation

Supporting Files

• src/videos/validators/index.ts - Exports for validators
• src/videos/dto/index.ts - Exports for DTOs

Tests

• src/videos/validators/is-valid-platforms.validator.spec.ts - Validator unit tests
• src/videos/dto/create-video.dto.spec.ts - DTO integration tests

Documentation

• src/videos/README.md - Complete usage guide

Usage Example

Before (Unsafe)

// Any value accepted - could cause failures
{
  targetPlatforms: "invalid" // ❌ String instead of array
}
{
  targetPlatforms: ["TIKTOK", "reddit"] // ❌ Invalid platform
}

After (Safe)

// Valid request
{
  targetPlatforms: ["TikTok", "Instagram", "TIKTOK"]
}

// Automatically normalized to:
{
  targetPlatforms: ["tiktok", "instagram"] // ✅ Lowercase + deduplicated
}

// Invalid request returns 400
{
  targetPlatforms: ["tiktok", "reddit"]
}
// Response: 400 Bad Request
// "Invalid platform(s): reddit. Supported platforms: tiktok, instagram, ..."

Integration Steps

To integrate this into your video endpoints:

1. Import the DTO in your controller:

import { CreateVideoDto, UpdateVideoDto } from './dto';

2. Use in controller methods:

@Post()
create(@Body() createVideoDto: CreateVideoDto) {
  // targetPlatforms is now validated and normalized
  return this.videosService.create(createVideoDto);
}

@Patch(':id')
update(@Param('id') id: string, @Body() updateVideoDto: UpdateVideoDto) {
  // targetPlatforms is validated and normalized
  return this.videosService.update(id, updateVideoDto);
}

3. Enable global validation pipe (if not already enabled):

// In main.ts
app.useGlobalPipes(new ValidationPipe({
  transform: true, // Enable transformation
  whitelist: true,
}));

Testing

Run tests after installing dependencies:

# Install dependencies
npm install

# Run validator tests
npm test -- --testPathPattern=is-valid-platforms.validator.spec

# Run DTO tests
npm test -- --testPathPattern=create-video.dto.spec

# Run all tests
npm test

Benefits

1. Type Safety - TypeScript types ensure compile-time safety
2. Runtime Validation - Prevents invalid data from entering the system
3. Automatic Normalization - Consistent data format in database
4. Clear Error Messages - Developers know exactly what went wrong
5. Extensible - Easy to add new platforms to the supported list
6. Well Tested - Comprehensive unit and integration tests

Next Steps

1. Install dependencies: npm install
2. Run tests to verify: npm test
3. Create a videos controller if it doesn't exist
4. Apply the DTOs to your video endpoints
5. Ensure global validation pipe is enabled in main.ts