Add configurable Lambda resources and Function URL support

[ncipollina]

Summary

This PR adds three new configurable properties to the Lambda construct to provide more flexibility and enable direct HTTP access:

• MemorySize (default: 1024 MB) - Configurable memory allocation instead of hardcoded 1024 MB
• TimeoutInSeconds (default: 6 seconds) - Configurable timeout instead of hardcoded 6 seconds
• GenerateUrl (default: false) - Optional Function URL generation for direct HTTP access without API Gateway

Key Features

🔧 Enhanced Lambda Configuration

• Memory and timeout are now customizable while maintaining backward compatibility
• Public readonly properties expose LambdaFunction and LiveAliasFunctionUrlDomain for advanced scenarios
• Function URLs provide direct HTTP access with automatic CloudFormation outputs

🧪 Comprehensive Testing Support

• Added 6 new assertion methods to LambdaFunctionConstructAssertions
• Enhanced test customization system with generateUrl parameter
• Updated fluent props builder with 4 new methods
• Added 9 comprehensive unit tests covering all new functionality

📖 Developer Experience

• Updated README with 3 new example sections showcasing the features
• Enhanced documentation with new configuration options and testing methods
• Backward compatibility maintained - all existing code continues to work

Examples

Custom Memory and Timeout

var lambda = new LambdaFunctionConstruct(this, "MyLambda", new LambdaFunctionConstructProps
{
    // ... existing props
    MemorySize = 2048,       // Custom memory (default: 1024 MB)
    TimeoutInSeconds = 30,   // Custom timeout (default: 6 seconds)
});

Function URL for Direct HTTP Access

var lambda = new LambdaFunctionConstruct(this, "MyApi", new LambdaFunctionConstructProps
{
    // ... existing props
    GenerateUrl = true,      // Enable Function URL
    MemorySize = 512,        // Optimized for lightweight API
    TimeoutInSeconds = 15,   // API timeout
});

// Access the function URL domain
string url = lambda.LiveAliasFunctionUrlDomain;

Enhanced Testing

// Fluent builder with new methods
var props = CdkTestHelper.CreatePropsBuilder("./lambda.zip")
    .WithMemorySize(2048)
    .WithTimeoutInSeconds(30)
    .WithGenerateUrl()
    .Build();

// New assertion helpers
template.ShouldHaveMemorySize(2048);
template.ShouldHaveTimeout(30);
template.ShouldHaveFunctionUrl();
template.ShouldHaveFunctionUrlOutput("stack", "construct");

Test Plan

• All 151 existing tests pass - backward compatibility verified
• 9 new comprehensive unit tests added covering:
  • Configurable memory size and timeout
  • Function URL generation (enabled/disabled scenarios)
  • Public properties exposure
  • Backward compatibility verification
  • Props builder functionality
  • Default value verification
• Test customization system enhanced with generateUrl parameter
• New assertion methods working correctly
• Build succeeds with no warnings or errors
• README examples verified and tested

Breaking Changes

None - this is a fully backward compatible enhancement. All existing functionality is preserved with sensible defaults.

🤖 Generated with Claude Code

[Copilot]

Pull Request Overview

This PR makes the Lambda construct’s memory size and timeout configurable and adds optional Function URL support, updating tests and documentation accordingly.

• Expose MemorySize, TimeoutInSeconds, and GenerateUrl in props and builder
• Wire through configuration into LambdaFunctionConstruct and add new function URL logic
• Update test fixtures, assertions, and README to cover and document the new options

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/.../LambdaFunctionConstructCustomization.cs	Pass new generateUrl flag into AutoFixture customizer
test/.../LambdaFunctionConstructAutoDataAttribute.cs	Accept generateUrl parameter for auto data attribute
test/LambdaFunctionConstructTests.cs	Add and update tests for memory, timeout, and URLs
src/.../LambdaFunctionConstructPropsBuilder.cs	Introduce WithMemorySize, WithTimeoutInSeconds, and WithGenerateUrl builder methods
src/.../LambdaFunctionConstructAssertions.cs	Add assertion helpers for memory, timeout, and URLs
src/.../Models/LambdaFunctionConstructProps.cs	Define new props with default memory, timeout, and URL flag
src/.../LambdaFunctionConstruct.cs	Apply configurable memory/timeout and conditional URL setup
README.md	Document new options and examples

Comments suppressed due to low confidence (2)

src/LayeredCraft.Cdk.Constructs/Models/LambdaFunctionConstructProps.cs:12

• MemorySize and TimeoutInSeconds are declared as double but AWS Lambda memory and timeout values must be integers. Consider using int types to improve type safety and prevent fractional values.

    double MemorySize { get; set; }

src/LayeredCraft.Cdk.Constructs/Testing/LambdaFunctionConstructPropsBuilder.cs:17

• The builder stores memory and timeout values as double. Consider using int to match the underlying integer-based AWS Lambda configuration and avoid fractional assignments.

    private double _memorySize = 1024;

[Copilot]

[nitpick] Throwing a generic Exception for assertion failures can obscure test failures. Consider using a more specific assertion helper or test framework assertion to deliver clearer error messages.