/
manager.go
82 lines (70 loc) · 1.63 KB
/
manager.go
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package cachemanager
import "errors"
// Vars
var (
ErrCacheFull = errors.New("Cache full")
ErrCacheMiss = errors.New("Cache miss")
ErrInvalidHandler = errors.New("Invalid handler")
ErrInputMustBeASliceOfBytes = errors.New("Input must be a slice of bytes")
)
// Manager represents a cache manager capable of switching between several cache handlers
type Manager interface {
AddHandler(n string, h Handler) Manager
Del(k string) error
Get(k string) (interface{}, error)
GetHandler(n string) (Handler, error)
Test() map[string]error
}
// NewManager creates a new cache manager
func NewManager() Manager {
return &manager{
handlers: make(map[string]Handler),
}
}
type manager struct {
handlers map[string]Handler
}
// AddHandler adds a new handler
func (m *manager) AddHandler(n string, h Handler) Manager {
m.handlers[n] = h
return m
}
func (m manager) Del(k string) error {
var e error
for _, h := range m.handlers {
e = h.Del(k)
if e != nil {
return e
}
}
return e
}
func (m manager) Get(k string) (interface{}, error) {
var v interface{}
var e error
for _, h := range m.handlers {
v, e = h.Get(k)
if e == nil || (e != nil && e.Error() != ErrCacheMiss.Error()) {
return v, e
}
}
return v, e
}
// GetHandler returns the handler
func (m manager) GetHandler(n string) (Handler, error) {
var e error
if h, ok := m.handlers[n]; ok {
return h, e
}
return nil, ErrInvalidHandler
}
func (m manager) Test() map[string]error {
// Initialize
o := make(map[string]error)
// Loop through handlers
for name, h := range m.handlers {
o[name] = h.Test()
}
// Return
return o
}