File System Client Example

fsclient.go

package daemon

import (
	"os"
)

// FileSystemClient abstracts file/directory manipulation operations
type FileSystemClient interface {
	Create(string) (os.File, error)
	Remove(string) error
	MkdirAll(string, os.FileMode) error
	Stat(string) (os.FileInfo, error)
	Symlink(string, string) error
	Chmod(os.FileMode) error
	Chown(int, int) error
}

// fsClient is internally used to hang the FileSystemClient functions on. It
// can also be used to hang mocks for testing.
type fsClient struct {
	Create   func(string) (os.File, error)
	Remove   func(string) error
	MkdirAll func(string, os.FileMode) error
	Stat     func(string) (os.FileInfo, error)
	Symlink  func(string, string) error
	Chmod    func(os.FileMode) error
	Chown    func(int, int) error
}

// NewFileSystemClient creates a new file system client using the default
// implementations provided by the os package.
func NewFileSystemClient() *fsClient {
	d := fsClient{
		d.Create:   os.Create,
		d.Remove:   os.Remove,
		d.MkdirAll: os.MkdirAll,
		d.Stat:     os.Stat,
		d.Symlink:  os.Symlink,
		d.Chmod:    os.Chmod,
		d.Chown:    os.Chown,
	}
	return &d
}