micro/config/config.go
Vasiliy Tolstov 3e40bac5f4 config: add helper funcs
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2021-09-30 01:24:16 +03:00

117 lines
2.9 KiB
Go

// Package config is an interface for dynamic configuration.
package config
import (
"context"
"errors"
"time"
)
// DefaultConfig default config
var DefaultConfig Config = NewConfig()
// DefaultWatcherMinInterval default min interval for poll changes
var DefaultWatcherMinInterval = 5 * time.Second
// DefaultWatcherMaxInterval default max interval for poll changes
var DefaultWatcherMaxInterval = 9 * time.Second
var (
// ErrCodecMissing is returned when codec needed and not specified
ErrCodecMissing = errors.New("codec missing")
// ErrInvalidStruct is returned when the target struct is invalid
ErrInvalidStruct = errors.New("invalid struct specified")
// ErrWatcherStopped is returned when source watcher has been stopped
ErrWatcherStopped = errors.New("watcher stopped")
)
// Config is an interface abstraction for dynamic configuration
type Config interface {
// Name returns name of config
Name() string
// Init the config
Init(opts ...Option) error
// Options in the config
Options() Options
// Load config from sources
Load(context.Context, ...LoadOption) error
// Save config to sources
Save(context.Context, ...SaveOption) error
// Watch a config for changes
Watch(context.Context, ...WatchOption) (Watcher, error)
// String returns config type name
String() string
}
// Watcher is the config watcher
type Watcher interface {
// Next blocks until update happens or error returned
Next() (map[string]interface{}, error)
// Stop stops watcher
Stop() error
}
// Load loads config from config sources
func Load(ctx context.Context, cs []Config, opts ...LoadOption) error {
var err error
for _, c := range cs {
if err = c.Init(); err != nil {
return err
}
if err = c.Load(ctx, opts...); err != nil {
return err
}
}
return nil
}
var (
DefaultAfterLoad = func(ctx context.Context, c Config) error {
for _, fn := range c.Options().AfterLoad {
if err := fn(ctx, c); err != nil {
c.Options().Logger.Errorf(ctx, "%s AfterLoad err: %v", c.String(), err)
if !c.Options().AllowFail {
return err
}
}
}
return nil
}
DefaultAfterSave = func(ctx context.Context, c Config) error {
for _, fn := range c.Options().AfterSave {
if err := fn(ctx, c); err != nil {
c.Options().Logger.Errorf(ctx, "%s AfterSave err: %v", c.String(), err)
if !c.Options().AllowFail {
return err
}
}
}
return nil
}
DefaultBeforeLoad = func(ctx context.Context, c Config) error {
for _, fn := range c.Options().BeforeLoad {
if err := fn(ctx, c); err != nil {
c.Options().Logger.Errorf(ctx, "%s BeforeLoad err: %v", c.String(), err)
if !c.Options().AllowFail {
return err
}
}
}
return nil
}
DefaultBeforeSave = func(ctx context.Context, c Config) error {
for _, fn := range c.Options().BeforeSave {
if err := fn(ctx, c); err != nil {
c.Options().Logger.Errorf(ctx, "%s BeforeSavec err: %v", c.String(), err)
if !c.Options().AllowFail {
return err
}
}
}
return nil
}
)