cli

README

cli

Shared configuration and error handling for the melange CLI.

Responsibility

This package provides infrastructure shared across CLI commands:

• Configuration loading - Discovers and parses melange.yaml with proper precedence (flags > env > config > defaults)
• Exit codes - Standardized exit codes for different failure modes
• Error wrapping - Typed errors that carry exit codes for proper CLI behavior

Architecture Role

cmd/melange/main.go
       │
       ├── internal/cli (config, errors)
       │
       └── individual command handlers

The CLI commands use this package to:

1. Load configuration from melange.yaml or environment
2. Build database connection strings
3. Return structured errors with appropriate exit codes

Key Components

• Config - Top-level configuration struct with database, generate, migrate, and doctor settings
• LoadConfig() - Discovers config file by walking up to .git boundary
• ExitError - Error type carrying exit code for os.Exit()
• Exit code constants (ExitConfig, ExitSchemaParse, ExitDBConnect)

Configuration Precedence

1. CLI flags (highest)
2. Environment variables (MELANGE_*)
3. Config file (melange.yaml)
4. Defaults (lowest)

Documentation

Overview

Package cli provides shared configuration and utilities for the melange CLI.

Index

• Constants
• func ExitWithError(err error)
• type ClientConfig
• type Config
  • func LoadConfig(explicitConfigPath string) (*Config, string, error)
  • func (c *Config) DSN() (string, error)
  • func (c *Config) ResolvedSchema() string
• type DatabaseConfig
• type DoctorConfig
• type ExitError
  • func ConfigError(msg string, err error) *ExitError
  • func DBConnectError(msg string, err error) *ExitError
  • func GeneralError(msg string, err error) *ExitError
  • func SchemaParseError(msg string, err error) *ExitError
  • func (e *ExitError) Error() string
  • func (e *ExitError) Unwrap() error
• type GenerateConfig
• type MigrateConfig

Constants

const (
	ExitSuccess     = 0
	ExitGeneral     = 1
	ExitConfig      = 2
	ExitSchemaParse = 3
	ExitDBConnect   = 4
)

Exit codes per spec.

Functions

func ExitWithError

func ExitWithError(err error)

ExitWithError prints the error and exits with the appropriate code.

Types

type ClientConfig

type ClientConfig struct {
	Runtime string `mapstructure:"runtime"`
	Schema  string `mapstructure:"schema"`
	Output  string `mapstructure:"output"`
	Package string `mapstructure:"package"`
	Filter  string `mapstructure:"filter"`
	IDType  string `mapstructure:"id_type"`
}

ClientConfig holds client code generation settings.

type Config

type Config struct {
	// Schema is the path to the OpenFGA schema file (e.g., "schemas/schema.fga")
	Schema string `mapstructure:"schema"`

	// Database configuration
	Database DatabaseConfig `mapstructure:"database"`

	// Per-command configuration
	Generate GenerateConfig `mapstructure:"generate"`
	Migrate  MigrateConfig  `mapstructure:"migrate"`
	Doctor   DoctorConfig   `mapstructure:"doctor"`
}

Config represents the melange configuration from melange.yaml.

func LoadConfig

func LoadConfig(explicitConfigPath string) (*Config, string, error)

LoadConfig discovers and loads configuration with proper precedence: flags > env > config file > defaults.

Returns the loaded config, the path to the config file (empty if none found), and any error encountered.

func (*Config) DSN

func (c *Config) DSN() (string, error)

DSN returns the database connection string. If database.url is set, it's returned directly. Otherwise, builds a DSN from discrete fields.

func (*Config) ResolvedSchema

func (c *Config) ResolvedSchema() string

ResolvedSchema returns the effective schema path, with generate.client.schema taking precedence over top-level schema (for generate command).

type DatabaseConfig

type DatabaseConfig struct {
	URL      string `mapstructure:"url"`
	Host     string `mapstructure:"host"`
	Port     int    `mapstructure:"port"`
	Name     string `mapstructure:"name"`
	User     string `mapstructure:"user"`
	Password string `mapstructure:"password"`
	SSLMode  string `mapstructure:"sslmode"`
}

DatabaseConfig holds database connection settings.

type DoctorConfig

type DoctorConfig struct {
	Verbose bool `mapstructure:"verbose"`
}

DoctorConfig holds doctor command settings.

type ExitError

type ExitError struct {
	Code    int
	Message string
	Err     error
}

ExitError wraps an error with an exit code.

func ConfigError

func ConfigError(msg string, err error) *ExitError

ConfigError creates an ExitError with ExitConfig code.

func DBConnectError

func DBConnectError(msg string, err error) *ExitError

DBConnectError creates an ExitError with ExitDBConnect code.

func GeneralError

func GeneralError(msg string, err error) *ExitError

GeneralError creates an ExitError with ExitGeneral code.

func SchemaParseError

func SchemaParseError(msg string, err error) *ExitError

SchemaParseError creates an ExitError with ExitSchemaParse code.

func (*ExitError) Error

func (e *ExitError) Error() string

func (*ExitError) Unwrap

func (e *ExitError) Unwrap() error

type GenerateConfig

type GenerateConfig struct {
	Client ClientConfig `mapstructure:"client"`
}

GenerateConfig holds code generation settings.

type MigrateConfig

type MigrateConfig struct {
	DryRun bool `mapstructure:"dry_run"`
	Force  bool `mapstructure:"force"`
}

MigrateConfig holds migration settings.