go-transform

A flexible Go-based text transformation tool that uses a plugin architecture to process input streams. This project demonstrates the Dependency Inversion Principle with three distinct layers, emphasizing modularity through its plugin system.

I wrote about an earlier version of this project on my blog, check it out for more context.

Features

• Plugin-based architecture for extensible text transformations
• Clean separation of concerns following Clean Architecture principles
• Simple CLI interface

Prerequisites

• Go 1.23 or later
• Make

Installation

# Clone the repository
git clone https://github.com/cekrem/go-transform.git
cd go-transform

# Build the main application and plugins
make

Usage

The tool reads from standard input and writes to standard output:

# Using the default passthrough transformer
echo "Hello, World!" | ./build/transform

# Using a specific transformer
echo "Hello, World!" | ./build/transform -transformer=passthrough

Project Structure

.
├── cmd/                 # Application entrypoint
├── pkg/
│   └── domain/         # Core business rules and interfaces
├── internal/
│   └── app/           # Application logic
│       └── processor/ # Transformation orchestration
└── plugins/           # Infrastructure implementations (plugins)

Architecture

This project demonstrates Clean Architecture principles with three layers:

Domain Layer (pkg/domain)

• Contains core business rules and interfaces
• Has no external dependencies
• Defines what transformers should do
• Transformer and Plugin interfaces

Application Layer (internal/app)

• Contains core application logic
• Depends only on domain interfaces
• Coordinates the transformation process
• Processor that manages plugins and executes transformations

Infrastructure Layer (plugins)

• Contains concrete implementations
• Depends on domain interfaces
• Implements specific transformation strategies
• passthrough plugin

The project follows the Dependency Inversion Principle by:

1. Defining abstractions in the domain layer
2. Having both application and infrastructure layers depend on domain interfaces
3. Ensuring all dependencies point toward the domain layer

Development

Creating New Plugins

Plugins should be created in the plugins directory and implement the transformer interface from the domain layer. See the passthrough plugin for an example implementation.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.