kops/util/pkg/vfs/memfs.go

149 lines
3.0 KiB
Go

/*
Copyright 2016 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package vfs
import (
"os"
"path"
"strings"
"sync"
)
type MemFSPath struct {
context *MemFSContext
location string
mutex sync.Mutex
contents []byte
children map[string]*MemFSPath
}
var _ Path = &MemFSPath{}
type MemFSContext struct {
clusterReadable bool
root *MemFSPath
}
func NewMemFSContext() *MemFSContext {
c := &MemFSContext{}
c.root = &MemFSPath{
context: c,
location: "",
}
return c
}
// MarkClusterReadable pretends the current memfscontext is cluster readable; this is useful for tests
func (c *MemFSContext) MarkClusterReadable() {
c.clusterReadable = true
}
func (c *MemFSPath) IsClusterReadable() bool {
return c.context.clusterReadable
}
var _ HasClusterReadable = &MemFSPath{}
func NewMemFSPath(context *MemFSContext, location string) *MemFSPath {
return context.root.Join(location).(*MemFSPath)
}
func (p *MemFSPath) Join(relativePath ...string) Path {
p.mutex.Lock()
defer p.mutex.Unlock()
joined := path.Join(relativePath...)
tokens := strings.Split(joined, "/")
current := p
for _, token := range tokens {
if current.children == nil {
current.children = make(map[string]*MemFSPath)
}
child := current.children[token]
if child == nil {
child = &MemFSPath{
context: p.context,
location: path.Join(current.location, token),
}
current.children[token] = child
}
current = child
}
return current
}
func (p *MemFSPath) WriteFile(data []byte, acl ACL) error {
p.contents = data
return nil
}
func (p *MemFSPath) CreateFile(data []byte, acl ACL) error {
// Check if exists
if p.contents != nil {
return os.ErrExist
}
return p.WriteFile(data, acl)
}
func (p *MemFSPath) ReadFile() ([]byte, error) {
if p.contents == nil {
return nil, os.ErrNotExist
}
// TODO: Copy?
return p.contents, nil
}
func (p *MemFSPath) ReadDir() ([]Path, error) {
var paths []Path
for _, f := range p.children {
paths = append(paths, f)
}
return paths, nil
}
func (p *MemFSPath) ReadTree() ([]Path, error) {
var paths []Path
p.readTree(&paths)
return paths, nil
}
func (p *MemFSPath) readTree(dest *[]Path) {
for _, f := range p.children {
*dest = append(*dest, f)
f.readTree(dest)
}
}
func (p *MemFSPath) Base() string {
return path.Base(p.location)
}
func (p *MemFSPath) Path() string {
return "memfs://" + p.location
}
func (p *MemFSPath) String() string {
return p.Path()
}
func (p *MemFSPath) Remove() error {
p.contents = nil
return nil
}