Finished task 5

[DamirSt]

Module 5: Import Service Implementation

What was done?

Core Import Service Implementation

✅ Complete import service infrastructure with S3 integration and CSV processing capabilities

CDK Stack and S3 Infrastructure

• Created ImportServiceStack with proper repository structure following ProductServiceStack pattern
• Implemented S3 bucket import-service-bucket-719484290433 with versioning and encryption
• Configured IAM policies for Lambda functions with least-privilege access
• Added uploaded/ folder structure for file imports

Lambda Function: importProductsFile (50/50 points)

• Implemented Lambda function with API Gateway integration at GET /import endpoint
• Function generates signed URLs for CSV file uploads with 5-minute expiration
• Returns structured JSON response: {signedUrl, fileName, s3Key, expiresIn}
• Integrated with frontend environment configuration
• Used async/await patterns throughout implementation
• Covered by unit tests using aws-sdk-mock for S3 method mocking

Lambda Function: importFileParser (40/40 points)

• Created Lambda function triggered by S3 events for uploaded/ folder objects
• Implemented CSV parsing using readable streams with csv-parser package
• Added file management: moves processed files from uploaded/ to parsed/ folder
• Configured proper error handling without S3 event retry failures
• Used async/await patterns for all AWS SDK operations

Frontend Integration

• Updated environment.ts with import API endpoint configuration
• Fixed managed products table to display product titles correctly (name field instead of title)
• Enabled import functionality in production environment
• Deployed frontend changes to AWS CloudFront distribution

Additional Scope - Infrastructure and Testing

• Repository Structure: Maintained consistent folder organization across services
• Error Handling: Implemented comprehensive error handling with structured logging
• Security: Configured proper CORS headers and S3 bucket security policies
• Testing: Verified end-to-end functionality with test CSV files
• Deployment: Successfully deployed all changes to AWS infrastructure

Link to Import Service API

Base URL: https://i6nl249ace.execute-api.us-east-1.amazonaws.com/prod
Import Endpoint: https://i6nl249ace.execute-api.us-east-1.amazonaws.com/prod/import

API Usage Example

# Get signed URL for CSV upload
curl "https://i6nl249ace.execute-api.us-east-1.amazonaws.com/prod/import?fileName=products.csv"

# Response format
{
  "signedUrl": "https://import-service-bucket-719484290433.s3.us-east-1.amazonaws.com/uploaded/products.csv?X-Amz-Algorithm=...",
  "fileName": "products.csv",
  "s3Key": "uploaded/products.csv",
  "expiresIn": 300
}

Product Schema

CSV Import Format

The import service expects CSV files with the following product schema:

title,description,price,artist,category,genre,year,imageUrl
"Album Name","Album description",29.99,"Artist Name","Category","Genre",2021,"https://example.com/album.jpg"

Product Object Structure (API Response)

{
  "id": "uuid-generated",
  "name": "Album Name",
  "description": "Album description", 
  "price": 29.99,
  "artist": "Artist Name",
  "category": "Category",
  "genre": "Genre",
  "year": 2021,
  "imageUrl": "https://example.com/album.jpg",
  "count": 0,
  "inStock": false
}

Database Tables

• Products Table: products (partition key: id)
• Stock Table: stock (partition key: product_id)

Technical Implementation Details

AWS Services Used

• AWS Lambda: Node.js 20.x runtime for serverless functions
• Amazon S3: Object storage for CSV files with folder structure
• API Gateway: REST API endpoint for signed URL generation
• Amazon CloudFront: CDN for frontend application
• AWS CDK: Infrastructure as Code deployment
• AWS IAM: Role-based access control

Key Features Implemented

• Signed URL Generation: Secure file upload with temporary credentials
• CSV Parsing: Stream-based processing for memory efficiency
• File Management: Automated file organization (uploaded → parsed)
• Error Handling: Comprehensive error responses and logging
• Frontend Integration: Seamless import workflow in admin interface
• Security: Proper CORS configuration and S3 bucket policies

Testing and Verification

Test Results

• ✅ Signed URL generation working correctly
• ✅ CSV file upload successful
• ✅ File parsing and processing functional
• ✅ File movement from uploaded to parsed folder verified
• ✅ Frontend integration complete
• ✅ Managed products table displaying titles correctly

Files Modified/Created

infra/
├── lib/import-service/
│   ├── import-service-stack.ts     # CDK stack with S3 and Lambda configuration
│   ├── handler.ts                # Lambda functions (importProductsFile, importFileParser)
│   └── package.json              # Dependencies (csv-parser, AWS SDK)
└── bin/infra.ts                   # Updated with ImportServiceStack instantiation

FE/src/
├── environments/environment.ts        # Import API configuration
└── app/admin/manage-products/
    └── manage-products.component.html  # Fixed title display issue

Deployment Status

• Backend: All Lambda functions deployed and operational
• Frontend: Angular application deployed with latest changes
• Infrastructure: All CloudFormation stacks updated successfully
• API Endpoints: Live and tested
• S3 Bucket: Configured with proper event triggers

The import service is now fully operational and ready for the next module where SQS-based product creation will be implemented.