KD Gen

A powerful Go code generation tool for creating type-safe enums from YAML configuration files.

Overview

KD Gen is a CLI tool that generates Go enum types with useful helper methods from YAML configuration files. It helps you create type-safe enums with string representations, parsing functions, and more.

✨ Features

V1

• Generate type-safe enums (int, string, uint64, …)
• JSON support (MarshalJSON, UnmarshalJSON)
• Database/sql integration (Scan, Value for DB storage)

V2

• MCP Tools → expose enum generation as interactive tools:

Tools

Tool	Category	Description
list_methods	Enum	List all supported enum generation methods with descriptions.
show_config_structure	Config	Show the YAML structure for a valid enum configuration file.
example_config	Config	Generate an example enum config file for a given type (e.g., string, int).
validate_config	Config	Validate an enum YAML config against schema and supported types.
generate_enum	Codegen	Generate Go enum code from a provided YAML configuration.
explain_enum	Docs	Explain what a given enum config means and how it maps to generated code.
diff_config	Utility	Compare two enum YAML config files and show the differences.
format_config	Utility	Format and normalize enum YAML config files.

Go Version

This project is developed using Go 1.25.0. It should work with other recent Go versions as well.

Libraries Used

• github.com/dave/jennifer – Code generation for Go
• github.com/spf13/cobra – CLI command framework
• github.com/spf13/viper – Configuration management
• github.com/mitchellh/mapstructure – Decode generic map values to Go structs
• github.com/shopspring/decimal – Arbitrary-precision fixed-point decimal numbers
• github.com/mark3labs/mcp-go - A Go implementation of the Model Context Protocol (MCP), enabling seamless integration between LLM applications and external data sources and tools.

Installation

From Source

# Clone the repository
git clone https://github.com/khuong02/kd-gen.git
cd kd-gen

# Build the binary
go build -o ./build/kd-gen main.go

# Optional: Move to a directory in your PATH
mv ./build/kd-gen /usr/local/bin/

Using docker

# Build image
docker build -t kd-gen .

# Run
docker run --rm -v $(pwd):/app -w /app kd-gen \
  enum gen --package core --output ./example/enum/enum_gen.go --config ./example/enum/enum.yaml

Using Go Install

go install github.com/khuong02/kd-gen@latest

Using Homebrew

You can install KD Gen via Homebrew using a custom tap:

# Add the tap
brew tap khuong02/tap https://github.com/khuong02/homebrew-tap

# Install kd-gen
brew install kd-gen

## Usage

### Basic Usage

Create a YAML configuration file defining your enums:

```yaml
enums:
  - name: Lang
    type: string
    methods:
    - String|Parse|Normalize|JSON|SQL
    values:
      - name: LangEnglish
        display: "English"
        code: "en"
      - name: LangVietnamese
        display: "Vietnamese"
        code: "vi"
  - name: LogLevel
    type: int
    values:
      - name: Debug
      - name: Info
      - name: Warn
      - name: Error
      - name: Fatal

Then run the tool to generate the Go code:

kd-gen enum gen --package core --output ./example/enum/enum_gen.go --config ./example/enum/enum.yaml

Sample Run

# Create a config file
cat > enum.yaml << EOF
enums:
  - name: Status
    type: string
    methods:
    - String
    values:
      - name: StatusActive
        display: "active"
        code: 1
      - name: StatusInactive
        display: "inactive"
        code: 0
EOF

# Generate the enum code
kd-gen enum gen --package core --output status_enum.go --config enum.yaml

The generated file will contain:

• Status type definition
• Constants for each enum value
• String() method for string representation
• Parse function to convert strings to enum values
• Map of codes
• Slice of all values

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Generated Code Features

For each enum defined in your YAML file, the tool generates:

1. A type definition (string, int, etc.)
2. Constants for each enum value
3. A map of code values (if provided)
4. A slice containing all enum values
5. A String() method for string representation
6. A Parse function to convert strings to enum values
7. A Normalize() method for string enums

---

Configuration File Format

enums:
  - name: EnumName      # Name of the enum type
    methods:
    - string
    - parse
    - normalize
    - json
    - sql
    type: string|int    # Type of the enum (string, int, etc.)
    values:
      - name: ValueName     # Name of the enum constant
        display: "Display"  # String representation (optional)
        code: value         # Optional "Code" field → supports multiple types:

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🔌 MCP Integration

This project can also be used as an MCP server so Claude Desktop can call its tools directly.

👉 See MCP_GUIDE.md for full setup instructions.

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📚 References

Project	Purpose
mcp-go	Go implementation of the Model Context Protocol.
mcp-grafana	Example MCP server integrating with Grafana.

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License

MIT License