Advanced Usage

Azu provides advanced features for building sophisticated web applications. This section covers file uploads, content negotiation, environment management, and performance tuning techniques.

Overview

Advanced features in Azu are designed for:

• File handling with streaming and validation

• Content negotiation for multi-format APIs

• Environment management for different deployment scenarios

• Performance optimization for high-traffic applications

• Security hardening for production deployments

Architecture

Key Features

1. File Uploads

• Streaming file uploads with progress tracking

• File type validation and virus scanning

• Image processing and optimization

• Secure file storage with access controls

2. Content Negotiation

• Automatic format detection based on Accept headers

• Multi-format API responses (JSON, XML, HTML)

• Custom content type handlers

• Version-aware API responses

3. Environment Management

• Environment-specific configuration

• Feature flags and toggles

• Database connection pooling

• Logging and monitoring setup

4. Performance Tuning

• Response caching strategies

• Database query optimization

• Background job processing

• CDN integration

Quick Start

File Upload Endpoint

struct FileUploadEndpoint
  include Endpoint(FileUploadRequest, FileUploadResponse)

  post "/upload"

  def call : FileUploadResponse
    # Validate file
    unless request.file.valid?
      return FileUploadResponse.error("Invalid file")
    end

    # Process file
    file_info = process_upload(request.file)

    FileUploadResponse.success(file_info)
  end

  private def process_upload(file : UploadedFile) : FileInfo
    # Generate unique filename
    filename = "#{UUID.random}_#{file.filename}"

    # Save to storage
    File.write("uploads/#{filename}", file.content)

    # Process if image
    if file.image?
      process_image(filename)
    end

    FileInfo.new(
      id: UUID.random,
      filename: filename,
      size: file.size,
      content_type: file.content_type
    )
  end
end

Content Negotiation

struct UserEndpoint
  include Endpoint(UserRequest, UserResponse)

  get "/users/:id"

  def call : UserResponse
    user = find_user(params["id"])

    case content_type
    when "application/json"
      UserResponse.json(user)
    when "application/xml"
      UserResponse.xml(user)
    when "text/html"
      UserResponse.html(user)
    else
      UserResponse.json(user) # Default
    end
  end
end

Environment Configuration

# config/environments/development.cr
Azu::Environment.configure :development do |config|
  config.log_level = :debug
  config.database_url = "postgresql://localhost/azu_dev"
  config.cache_enabled = false
  config.hot_reload = true
end

# config/environments/production.cr
Azu::Environment.configure :production do |config|
  config.log_level = :info
  config.database_url = ENV["DATABASE_URL"]
  config.cache_enabled = true
  config.cdn_url = ENV["CDN_URL"]
  config.ssl_redirect = true
end

File Uploads

Azu provides comprehensive file upload capabilities with:

• Streaming uploads for large files

• File validation and security checks

• Image processing and optimization

• Progress tracking and resumable uploads

Learn more about File Uploads →

Content Negotiation

Content negotiation allows your API to serve multiple formats:

• Automatic format detection based on Accept headers

• Custom content type handlers

• Version-aware responses

• Multi-format serialization

Learn more about Content Negotiation →

Environment Management

Environment management helps you configure your application for different deployment scenarios:

• Environment-specific settings

• Feature flags and toggles

• Database and cache configuration

• Security and performance settings

Learn more about Environment Management →

Performance Tuning

Performance tuning techniques for high-traffic applications:

• Response caching strategies

• Database optimization

• Background job processing

• CDN and asset optimization

Learn more about Performance Tuning →

Security Best Practices

1. File Upload Security

• Validate file types and content

• Scan for malware and viruses

• Use secure file storage

• Implement access controls

2. API Security

• Use HTTPS in production

• Implement rate limiting

• Validate all input data

• Use proper authentication

3. Environment Security

• Use environment variables for secrets

• Implement proper logging

• Monitor for security issues

• Regular security updates

Performance Optimization

1. Caching Strategies

• Response caching for static content

• Database query caching

• Template fragment caching

• CDN integration for assets

2. Database Optimization

• Connection pooling

• Query optimization

• Index management

• Read replicas for scaling

3. Background Processing

• Async job processing

• File processing queues

• Email sending queues

• Data import/export jobs

Monitoring and Debugging

1. Application Monitoring

• Request/response logging

• Performance metrics

• Error tracking

• Health checks

2. Development Tools

• Hot reloading

• Debug logging

• Performance profiling

• Memory usage tracking

Next Steps

• File Uploads Deep Dive - Handle file uploads securely

• Content Negotiation Guide - Build multi-format APIs

• Environment Management - Configure for different environments

• Performance Tuning - Optimize your application

Examples

Check out the playground examples for complete working examples of:

• File upload with progress tracking

• Multi-format API responses

• Environment-specific configuration

• Performance optimization techniques

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Ready to build advanced features? Start with File Uploads to handle user file uploads, then explore Content Negotiation for building flexible APIs.