azu dev

The azu dev command provides an enhanced development environment with additional tools and features for productive development. It's an alternative to azu serve with extra development capabilities.

Overview

azu dev [options]

Basic Usage

Start Development Environment

# Start development environment
azu dev

# Start with custom port
azu dev --port 4000

# Start with specific environment
azu dev --env development

Development with Hot Reloading

# Start development server with enhanced features
azu dev

# Output:
# 🚀 Starting Azu development environment...
# 📦 Compiling application...
# ✅ Compilation successful!
# 🌐 Server running at: http://localhost:4000
# 🔥 Hot reloading enabled
# 👀 Watching for file changes...
# 📊 Development dashboard at: http://localhost:4000/dev
# 🧪 Test runner available
# 📝 Code formatter active
#
# Press Ctrl+C to stop the server

Command Options

Option	Description	Default
--port <port>	Server port	4000
--host <host>	Server host	localhost
--env <environment>	Environment name	development
--debug	Enable debug mode	true
--dashboard	Enable development dashboard	true
--tests	Enable test runner	true
--format	Enable code formatting	true
--lint	Enable linting	true
--coverage	Enable code coverage	false
--workers <number>	Number of worker processes	1

Development Features

Development Dashboard

Access the development dashboard at http://localhost:4000/dev:

# Dashboard features:
# - Application status
# - Database information
# - Route listing
# - Performance metrics
# - Error logs
# - Test results
# - Code coverage

Enhanced File Watching

# Watches additional file types
src/
├── *.cr                    # Crystal source files
├── endpoints/              # Endpoint files
├── models/                 # Model files
├── services/               # Service files
├── middleware/             # Middleware files
├── initializers/           # Initializer files
└── pages/                  # Page components

public/
├── assets/                 # Static assets
├── templates/              # Template files
└── *.css, *.js, *.html     # Static files

config/
├── *.yml                   # Configuration files
└── environments/           # Environment configs

spec/
├── *_spec.cr               # Test files
└── factories/              # Test factories

Automatic Code Formatting

# Automatically format code on save
# Uses crystal tool format

# Format specific files
crystal tool format src/models/user.cr

# Format entire project
crystal tool format src/

Linting and Code Quality

# Run Ameba linter automatically
# Checks for code quality issues

# Manual linting
ameba src/

# Fix auto-fixable issues
ameba --fix src/

Test Runner Integration

# Run tests automatically on file changes
# Tests run in background

# Manual test execution
crystal spec

# Run specific test files
crystal spec spec/models/user_spec.cr

# Run with coverage
crystal spec --coverage

Development Dashboard

Dashboard Features

Application Status:

• Server uptime

• Memory usage

• CPU usage

• Request count

• Error rate

Database Information:

• Connection status

• Migration status

• Table count

• Query performance

Route Listing:

• All registered routes

• HTTP methods

• Endpoint classes

• Route parameters

Performance Metrics:

• Response times

• Throughput

• Memory allocation

• Garbage collection

Error Logs:

• Recent errors

• Stack traces

• Error frequency

• Error categories

Test Results:

• Test status

• Coverage reports

• Failed tests

• Test performance

Accessing Dashboard

# Start development server
azu dev

# Access dashboard
# http://localhost:4000/dev

# Dashboard sections:
# /dev/status      - Application status
# /dev/database    - Database information
# /dev/routes      - Route listing
# /dev/performance - Performance metrics
# /dev/errors      - Error logs
# /dev/tests       - Test results
# /dev/coverage    - Code coverage

Examples

Basic Development

# Start development environment
azu dev

# Visit application
# http://localhost:4000

# Visit dashboard
# http://localhost:4000/dev

Custom Configuration

# Development with custom settings
azu dev --port 4000 --host 0.0.0.0 --debug

# Development without dashboard
azu dev --dashboard=false

# Development with coverage
azu dev --coverage

Team Development

# Share development server
azu dev --host 0.0.0.0 --port 4000

# Multiple developers can access:
# http://your-ip:4000
# http://your-ip:4000/dev

Development Workflow

1. Start Development

# Start development environment
azu dev

# In another terminal, run additional tools
crystal spec --watch
ameba --watch src/

2. Make Changes

# Edit files in src/
# Changes are automatically detected

# Server recompiles and restarts
# Tests run automatically
# Code is formatted
# Linting runs

3. Monitor Progress

# Check dashboard for:
# - Compilation status
# - Test results
# - Performance metrics
# - Error logs

# Visit: http://localhost:4000/dev

4. Debug Issues

# Check error logs in dashboard
# http://localhost:4000/dev/errors

# Check test failures
# http://localhost:4000/dev/tests

# Check performance issues
# http://localhost:4000/dev/performance

Advanced Features

Code Coverage

# Enable coverage tracking
azu dev --coverage

# View coverage in dashboard
# http://localhost:4000/dev/coverage

# Coverage includes:
# - Line coverage
# - Branch coverage
# - Function coverage
# - File coverage

Performance Profiling

# Enable performance profiling
azu dev --profile

# Profile information available in dashboard
# http://localhost:4000/dev/performance

# Profile data includes:
# - Request timing
# - Database queries
# - Memory usage
# - CPU usage

Database Monitoring

# Database monitoring in dashboard
# http://localhost:4000/dev/database

# Database information includes:
# - Connection status
# - Migration status
# - Query count
# - Query timing
# - Table sizes

Error Tracking

# Error tracking in dashboard
# http://localhost:4000/dev/errors

# Error information includes:
# - Error count
# - Error types
# - Stack traces
# - Error frequency
# - Error context

Configuration

Development Configuration

# config/environments/development.cr
Azu.configure do |config|
  config.debug = true
  config.log_level = :debug
  config.host = "localhost"
  config.port = 4000

  # Development-specific settings
  config.development.dashboard = true
  config.development.auto_format = true
  config.development.auto_lint = true
  config.development.test_runner = true
  config.development.coverage = false
end

Dashboard Configuration

# azu.yml
development:
  dashboard:
    enabled: true
    port: 4000
    host: localhost
    auth: false
    metrics:
      enabled: true
      interval: 5s
    tests:
      enabled: true
      auto_run: true
    coverage:
      enabled: false
      threshold: 80

Troubleshooting

Dashboard Not Accessible

# Check if dashboard is enabled
azu dev --dashboard=true

# Check dashboard port
# Default: http://localhost:4000/dev

# Check firewall settings
# Ensure port is accessible

Tests Not Running

# Check test configuration
azu dev --tests=true

# Run tests manually
crystal spec

# Check test files exist
ls -la spec/

Code Formatting Issues

# Check Crystal installation
crystal --version

# Run formatter manually
crystal tool format src/

# Check for syntax errors
crystal build src/main.cr

Performance Issues

# Reduce worker processes
azu dev --workers 1

# Disable features
azu dev --coverage=false --profile=false

# Check system resources
top
htop

Best Practices

1. Development Workflow

# Use azu dev for development
azu dev

# Use azu serve for simple testing
azu serve

# Use production build for performance testing
crystal build src/main.cr --release

2. Dashboard Usage

# Monitor dashboard regularly
# http://localhost:4000/dev

# Check for:
# - Compilation errors
# - Test failures
# - Performance issues
# - Database problems

3. Code Quality

# Keep code formatted
# crystal tool format runs automatically

# Fix linting issues
# ameba runs automatically

# Maintain test coverage
# Tests run automatically

4. Performance Monitoring

# Monitor performance in dashboard
# http://localhost:4000/dev/performance

# Watch for:
# - Slow requests
# - High memory usage
# - Database bottlenecks
# - Error spikes

Integration with IDEs

VS Code Integration

// .vscode/launch.json
{
  "version": "0.2.0",
  "configurations": [
    {
      "name": "Azu Dev",
      "type": "crystal",
      "request": "launch",
      "program": "${workspaceFolder}/src/main.cr",
      "args": ["dev", "--port", "4000"]
    }
  ]
}

JetBrains Integration

# Run configuration
# Program: src/main.cr
# Arguments: dev --port 4000
# Working directory: project root

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The azu dev command provides an enhanced development environment with dashboard, testing, formatting, and monitoring capabilities.

Next Steps:

• Development Workflows - Learn development patterns

• Testing Your Application - Comprehensive testing

• Database Commands - Manage your database