distribution/registry/storage/driver/factory/factory.go
Stephen J Day 65b0d73cb7 Move storagedriver package to registry/storage/driver
This change is slightly more complex than previous package maves in that the
package name changed. To address this, we simply always reference the package
driver as storagedriver to avoid compatbility issues with existing code. While
unfortunate, this can be cleaned up over time.

Signed-off-by: Stephen J Day <stephen.day@docker.com>
2015-02-11 12:43:04 -08:00

72 lines
2.7 KiB
Go

package factory
import (
"fmt"
storagedriver "github.com/docker/distribution/registry/storage/driver"
)
// driverFactories stores an internal mapping between storage driver names and their respective
// factories
var driverFactories = make(map[string]StorageDriverFactory)
// StorageDriverFactory is a factory interface for creating storagedriver.StorageDriver interfaces
// Storage drivers should call Register() with a factory to make the driver available by name
type StorageDriverFactory interface {
// Create returns a new storagedriver.StorageDriver with the given parameters
// Parameters will vary by driver and may be ignored
// Each parameter key must only consist of lowercase letters and numbers
Create(parameters map[string]interface{}) (storagedriver.StorageDriver, error)
}
// Register makes a storage driver available by the provided name.
// If Register is called twice with the same name or if driver factory is nil, it panics.
func Register(name string, factory StorageDriverFactory) {
if factory == nil {
panic("Must not provide nil StorageDriverFactory")
}
_, registered := driverFactories[name]
if registered {
panic(fmt.Sprintf("StorageDriverFactory named %s already registered", name))
}
driverFactories[name] = factory
}
// Create a new storagedriver.StorageDriver with the given name and parameters
// To run in-process, the StorageDriverFactory must first be registered with the given name
// If no in-process drivers are found with the given name, this attempts to create an IPC driver
// If no in-process or external drivers are found, an InvalidStorageDriverError is returned
func Create(name string, parameters map[string]interface{}) (storagedriver.StorageDriver, error) {
driverFactory, ok := driverFactories[name]
if !ok {
return nil, InvalidStorageDriverError{name}
// NOTE(stevvooe): We are disabling storagedriver ipc for now, as the
// server and client need to be updated for the changed API calls and
// there were some problems libchan hanging. We'll phase this
// functionality back in over the next few weeks.
// No registered StorageDriverFactory found, try ipc
// driverClient, err := ipc.NewDriverClient(name, parameters)
// if err != nil {
// return nil, InvalidStorageDriverError{name}
// }
// err = driverClient.Start()
// if err != nil {
// return nil, err
// }
// return driverClient, nil
}
return driverFactory.Create(parameters)
}
// InvalidStorageDriverError records an attempt to construct an unregistered storage driver
type InvalidStorageDriverError struct {
Name string
}
func (err InvalidStorageDriverError) Error() string {
return fmt.Sprintf("StorageDriver not registered: %s", err.Name)
}