drapergem/draper
Draper
Draper is a presentation layer framework and decorator library for Ruby on Rails that implements the view-model pattern. It serves as a proxy-based system to separate presentation logic from business models, allowing view-specific data transformations to be isolated from the underlying data.
The framework provides specialized capabilities for managing how data is displayed, including the ability to wrap single objects or entire collections. It supports recursive decoration for associated models and the injection of view context and request state into decorators to allow for conditional presentation.
Additional functionality includes the delegation of methods and class-level finders to the wrapped model, integration with view helpers for data formatting, and the use of global identifiers to maintain decoration state during background job serialization.
A command line tool is provided to generate decorator files.
Features
- Object Decoration - Wrap a model instance in a decorator to provide specialized presentation methods for a single record.
- Logic and Presentation Separation - Isolates view-specific formatting and presentation logic from business models to keep core logic clean.
- UI and View Helpers - Use helper methods within decorators to transform raw data into human-readable formats for the user interface.
- View Helpers - Use application and framework view helpers directly within a decorator class.
- Object Decoration - Apply a decorator to a model instance or collection to add presentation methods without altering the underlying data.
- Delegate Message Forwarders - Forwards method calls not defined in the decorator to the underlying model object to maintain original data access.
- Proxy Objects - Uses a proxy-based system to intercept and extend the behavior of model objects for presentation.
- Request Context Injection - Injects controller and request state into decorator instances to allow conditional presentation based on the current session.
- Collection Decoration - Apply decorators to groups of objects to add custom methods for tasks like pagination.
- Recursive Decoration - Automatically wraps associated model instances in decorators when the parent object is decorated to ensure consistent formatting.
- Domain Data Presentation Layers - Establishes a dedicated presentation layer for transforming domain data into view-ready formats.
- Method Delegation - Forward method calls not defined in the decorator directly to the underlying model object.
- Presentation Layer Frameworks - Acts as a presentation layer framework that isolates view-specific data transformations from business logic.
- Model-View-Controller Patterns - Implements an architectural separation between data models and the presentation layer.
- Model-View-ViewModel - Implements the Model-View-ViewModel pattern by wrapping model objects to provide UI-specific methods.
- Decorator Libraries - Provides a specialized decorator library for Ruby on Rails to separate presentation logic from models.
- View Models - Provides a view-modeling system to transform raw Rails model data into human-readable formats.
- Automatic Controller Decoration - Wrap model instance variables in decorators before they reach view templates.
- Automatic Variable Wrapping - Automatically wraps model instance variables in decorators before they reach view templates.
- Class-Level Method Mapping - Routes class-level finders and constants from the decorator to the wrapped model class for seamless data retrieval.
- Decorated Finder Proxying - Call database finder methods on a decorator class to return results that are already decorated.
- Context Object Passing - Allows passing request and session state into decorators via a context object to enable conditional presentation.
- Class Method Mapping - Provides the ability to call database finders and class methods directly on a decorator class.
- View Context Injections - Inject and access controller or view level context within a decorator for conditional presentation.
- Decorators - Add object-oriented presentation layers to Rails models.
- More to explore - Adds presentation logic.
Star history
How this analysis was created: This summary and feature list were written by an AI model that read the project's README and public documentation pages. Each feature links to the documentation it came from; stars, license and language come straight from the GitHub API. The model does not read the source code, and the analysis is refreshed when the project is re-analysed. Learn more on our About page.
