README.md

Tests

This directory contains tests for the Docker Graceful Shutdown utility.

Test Categories

1. Basic Functionality Tests (Test-DockerGracefulShutdown.ps1)

   • Core script functionality
   • Docker environment checks
   • Container management operations
   • Error handling
   • Progress display formatting

2. Dependency Tests (Test-Dependencies.ps1)

   • Network dependency detection
     • Basic network dependencies
     • Multi-network container relationships
     • Custom network isolation
   • Docker Compose dependency resolution
     • Direct dependencies via depends_on
     • Network-based implicit dependencies
   • Complex multi-tier scenarios
     • Microservices architecture simulation
     • Frontend/Backend separation
     • Database tier isolation
   • Dependency graph validation
   • Shutdown order verification
   • Circular dependency detection
   • Intelligent dependency resolution

Test Safety

All tests are designed to be safe and isolated:

• Test containers use unique prefixed names (e.g., test-graceful-)
• Automatic cleanup after each test run
• No interference with existing containers
• Separate test networks and resources
• Validation checks to prevent interaction with non-test containers
• Error handling for container startup/shutdown
• Timeout mechanisms for container operations

Running Tests

Prerequisites

# Requires PowerShell 5.1 or later
#Requires -Version 5.1
#Requires -Modules @{ ModuleName="Pester"; ModuleVersion="5.0.0" }

# Install required modules
Install-Module -Name Pester -MinimumVersion 5.0.0 -Force -SkipPublisherCheck

Local Testing

# Run all tests with detailed output
Invoke-Pester ./tests/*.ps1 -Output Detailed

# Run specific test categories
Invoke-Pester ./tests/Test-DockerGracefulShutdown.ps1 -Output Detailed
Invoke-Pester ./tests/Test-Dependencies.ps1 -Output Detailed

Test Structure

The tests follow PowerShell best practices:

• Comment-based help for all test files
• Proper function documentation
• Type declarations for parameters
• Error handling with try-catch blocks
• Cleanup in finally blocks
• Helper functions for common operations
• Descriptive test contexts and names

Test Scenarios

Network Dependencies Test

Describe "Container Dependency Tests" {
    Context "When testing network dependencies" {
        It "Should detect containers in the same network" {
            # Tests basic network dependency detection
        }
    }
}

Docker Compose Dependencies Test

Context "When testing Docker Compose style dependencies" {
    It "Should detect network-based dependencies" {
        # Tests compose-style dependency resolution
    }
}

Complex Multi-Tier Test

Context "When testing complex multi-tier dependencies" {
    It "Should handle multiple network dependencies" {
        # Tests complex microservices scenarios
    }
}

Test Coverage

The dependency tests cover:

1. Network Dependencies

   • Basic container networking
   • Network isolation
   • Cross-network communication
   • Default bridge network handling

2. Docker Compose Scenarios

   • Multi-container applications
   • Service dependencies
   • Network-based service discovery
   • Container startup order

3. Complex Dependencies

   • Microservices architectures
   • Multi-tier applications
   • Database dependencies
   • Circular dependency detection
   • Load balancer scenarios
   • Shared resource management

Helper Functions

The test suite includes several helper functions:

• Wait-ContainerStart: Smart container startup detection
• New-TestContainer: Creates containers for testing
• Remove-TestContainers: Cleans up test containers
• Test-ContainerNetwork: Validates network connectivity
• Get-ContainerDependencies: Analyzes container dependencies

Error Handling

Tests include comprehensive error handling:

• Container startup failures
• Network creation issues
• Timeout scenarios
• Resource cleanup
• Invalid configurations
• Network connectivity problems