README
¶
Config
Robust configuration management wrapping spf13/viper with type safety and interface-based testability.
Features:
- Mockable
Containableinterface - Automatic environment variable mapping
- Built-in observer pattern for file watching
- Support for YAML, embedded assets, and more
For detailed documentation, usage examples, and testing strategies, see the Config Component Documentation.
Documentation
¶
Overview ¶
Package config provides configuration loading, merging, and access via the Containable interface backed by Viper.
Configurations can be loaded from multiple sources — local files, embedded assets, environment variables, and command-line flags — and merged with deterministic precedence. Factory functions include NewFilesContainer, LoadFilesContainer, NewReaderContainer, and NewContainerFromViper.
Type-safe accessors (GetString, GetInt, GetBool, GetDuration, GetTime, etc.) are exposed through Containable. For advanced use cases, [Containable.GetViper] provides direct access to the underlying Viper instance as an intentional power-user escape hatch.
Hot-reload is supported via the Observable interface, which allows consumers to register callbacks that fire when configuration files change on disk.
Index ¶
- Variables
- func LoadEnv(fs afero.Fs, logger logger.Logger)
- type Containable
- type Container
- func (c *Container) AddObserver(o Observable)
- func (c *Container) AddObserverFunc(f func(Containable, chan error))
- func (c *Container) Dump(w io.Writer)
- func (c *Container) Get(key string) any
- func (c *Container) GetBool(key string) bool
- func (c *Container) GetDuration(key string) time.Duration
- func (c *Container) GetFloat(key string) float64
- func (c *Container) GetInt(key string) int
- func (c *Container) GetObservers() []Observable
- func (c *Container) GetString(key string) string
- func (c *Container) GetTime(key string) time.Time
- func (c *Container) GetViper() *viper.Viper
- func (c *Container) Has(key string) bool
- func (c *Container) IsSet(key string) bool
- func (c *Container) Set(key string, value any)
- func (c *Container) Sub(key string) Containable
- func (c *Container) ToJSON() string
- func (c *Container) WriteConfigAs(dest string) error
- type Observable
- type Observer
Constants ¶
This section is empty.
Variables ¶
var (
ErrNoFilesFound = errors.Newf("no configuration files found please run init, or provide a config file using the --config flag")
)
Functions ¶
Types ¶
type Containable ¶
type Containable interface {
Get(key string) any
GetBool(key string) bool
GetInt(key string) int
GetFloat(key string) float64
GetString(key string) string
GetTime(key string) time.Time
GetDuration(key string) time.Duration
// GetViper returns the underlying Viper instance for advanced operations
// not exposed by the Containable interface. This is an intentional escape
// hatch for power users who need Viper's full API (e.g., MergeConfig,
// BindPFlag, or direct access to config file watching).
//
// Prefer the typed accessor methods (GetString, GetInt, etc.) for standard
// configuration reads. Use GetViper only when the Containable interface
// does not cover your use case.
GetViper() *viper.Viper
Has(key string) bool
IsSet(key string) bool
Set(key string, value any)
WriteConfigAs(dest string) error
Sub(key string) Containable
AddObserver(o Observable)
AddObserverFunc(f func(Containable, chan error))
ToJSON() string
Dump(w io.Writer)
}
func LoadFilesContainer ¶
LoadFilesContainer loads configuration from files and returns a Containable. It returns an error if the first file specified does not exist.
type Container ¶
type Container struct {
ID string
// contains filtered or unexported fields
}
Container container for configuration.
func NewContainerFromViper ¶
NewContainerFromViper creates a new Container from an existing Viper instance.
func NewFilesContainer ¶
NewFilesContainer Initialise configuration container to read files from the FS.
func NewReaderContainer ¶
NewReaderContainer Initialise configuration container to read config from ioReader.
func (*Container) AddObserver ¶
func (c *Container) AddObserver(o Observable)
AddObserver attach observer to trigger on config update.
func (*Container) AddObserverFunc ¶
func (c *Container) AddObserverFunc(f func(Containable, chan error))
AddObserverFunc attach function to trigger on config update.
func (*Container) GetDuration ¶
GetDuration get duration value from config.
func (*Container) GetObservers ¶
func (c *Container) GetObservers() []Observable
GetObservers retrieve all currently attached Observers.
func (*Container) Sub ¶
func (c *Container) Sub(key string) Containable
Sub returns a subtree of the parent configuration.
func (*Container) WriteConfigAs ¶
WriteConfigAs writes the current configuration to the given path.
type Observable ¶
type Observable interface {
Run(Containable, chan error)
}
Source Files