Make handler field support only snake_case in configuration

[Copilot]

This PR implements a breaking change to make the handler field in endpoint configuration files support only snake_case naming, matching the same enforcements of the auth.type field.

Changes Made

Before this change:

# endpoint.yml
path: /webhook
handler: GitHubHandler  # PascalCase required

After this change:

# endpoint.yml  
path: /webhook
handler: github_handler  # snake_case required

Implementation Details

• Updated ConfigValidator: Changed validation pattern from /\A[A-Z][a-zA-Z0-9_]*\z/ to /\A[a-z][a-z0-9_]*\z/ to only accept snake_case handler names
• Updated PluginLoader: Modified get_handler_plugin method to convert snake_case configuration values to PascalCase for internal class lookup
• Maintained Internal Structure: File naming (github_handler.rb) and class names (GithubHandler) remain unchanged - only configuration references use snake_case
• Security Validation: Updated dangerous class validation to convert snake_case to PascalCase before checking against the security blacklist

Example Usage

If you have a handler file handlers/github_handler.rb with contents:

class GithubHandler < Hooks::Plugins::Handlers::Base
  def call(payload:, headers:, env:, config:)
    # Process GitHub webhook
    { status: "success" }
  end
end

It should now be referenced as handler: github_handler in endpoint configurations (previously handler: GithubHandler).

Breaking Change Notice

This is an intentional breaking change with no backwards compatibility. All existing endpoint configurations using PascalCase handler names must be updated to use snake_case.

Testing

• All existing tests updated to use snake_case handler names
• Added comprehensive validation for snake_case patterns
• Maintained 100% test coverage (562 examples, 0 failures)
• All linting checks pass

Fixes #53.

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[Copilot]

Pull Request Overview

This PR enforces snake_case naming for the handler field in endpoint configurations, updating validation, loading, and tests to match the new convention.

• Updated ConfigValidator to only accept snake_case handler names and convert them to PascalCase for security checks
• Modified PluginLoader to transform snake_case config values into PascalCase for internal class lookup
• Revised tests and helper methods to use snake_case everywhere and maintain 100% coverage

Reviewed Changes

Copilot reviewed 48 out of 14 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
lib/hooks/core/config_validator.rb	Changed handler-name regex to snake_case and adjusted dangerous-class check
lib/hooks/core/plugin_loader.rb	Added snake_case → PascalCase conversion for lookup
lib/hooks/app/helpers.rb	Updated docstring to reflect snake_case parameter
spec/unit/lib/hooks/handlers/base_spec.rb	Updated test expectations from PascalCase to snake_case
spec/unit/lib/hooks/core/config_validator_spec.rb	Switched handler fixtures to snake_case
spec/unit/lib/hooks/core/config_validator_security_spec.rb	Updated security tests for snake_case and PascalCase failures
spec/unit/lib/hooks/core/plugin_loader_spec.rb	Adjusted plugin lookup tests to use snake_case
spec/unit/lib/hooks/app/helpers_spec.rb	Updated helper load expectations
spec/unit/lib/hooks/app/helpers_security_spec.rb	Updated helper security tests to snake_case
spec/unit/app/rack_env_builder_spec.rb	Switched handler in rack env to snake_case
spec/integration/hooks_integration_spec.rb	Updated integration YAML fixture to snake_case
spec/integration/global_lifecycle_hooks_spec.rb	Updated global-lifecycle YAML fixture to snake_case
.bundle/config	Bundler path updates (unrelated to handler change)

Comments suppressed due to low confidence (2)

spec/unit/lib/hooks/core/plugin_loader_spec.rb:166

• We only test default_handler → DefaultHandler; consider adding a test case for a handler name containing a number (e.g. team_1_handler) to verify the snake_case→PascalCase conversion handles digits correctly.

      expect(described_class.get_handler_plugin("default_handler")).to eq(DefaultHandler)

.bundle/config:3

• [nitpick] This CI/deployment configuration change is unrelated to the handler naming change and pollutes the PR; consider removing or splitting it into its own commit.

BUNDLE_PATH: "/home/runner/work/hooks/hooks/vendor/bundle"