blob: e9a4ffa8ccc87e7f665afb023862354ccb99d4a0 [file] [log] [blame]
/*
* Copyright 2018-present Open Networking Foundation
* 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 model
import (
"github.com/opencord/voltha-go/common/log"
"runtime/debug"
"sync"
"time"
)
type singletonProxyAccessControl struct {
sync.RWMutex
cache map[string]ProxyAccessControl
}
var instanceProxyAccessControl *singletonProxyAccessControl
var onceProxyAccessControl sync.Once
// PAC provides access to the proxy access control singleton instance
func PAC() *singletonProxyAccessControl {
onceProxyAccessControl.Do(func() {
instanceProxyAccessControl = &singletonProxyAccessControl{cache: make(map[string]ProxyAccessControl)}
})
return instanceProxyAccessControl
}
// ReservePath will apply access control for a specific path within the model
func (singleton *singletonProxyAccessControl) ReservePath(path string, proxy *Proxy, pathLock string) ProxyAccessControl {
singleton.Lock()
defer singleton.Unlock()
var pac ProxyAccessControl
var exists bool
if pac, exists = singleton.cache[path]; !exists {
pac = NewProxyAccessControl(proxy, pathLock)
singleton.cache[path] = pac
}
if exists {
log.Debugf("PAC exists for path: %s... re-using", path)
} else {
log.Debugf("PAC does not exists for path: %s... creating", path)
}
return pac
}
// ReleasePath will remove access control for a specific path within the model
func (singleton *singletonProxyAccessControl) ReleasePath(pathLock string) {
singleton.Lock()
defer singleton.Unlock()
delete(singleton.cache, pathLock)
}
// ProxyAccessControl is the abstraction interface to the base proxyAccessControl structure
type ProxyAccessControl interface {
Get(path string, depth int, deep bool, txid string, control bool) interface{}
Update(path string, data interface{}, strict bool, txid string, control bool) interface{}
Add(path string, data interface{}, txid string, control bool) interface{}
Remove(path string, txid string, control bool) interface{}
SetProxy(proxy *Proxy)
}
// proxyAccessControl holds details of the path and proxy that requires access control
type proxyAccessControl struct {
sync.RWMutex
Proxy *Proxy
PathLock chan struct{}
Path string
start time.Time
stop time.Time
}
// NewProxyAccessControl creates a new instance of an access control structure
func NewProxyAccessControl(proxy *Proxy, path string) ProxyAccessControl {
return &proxyAccessControl{
Proxy: proxy,
Path: path,
PathLock: make(chan struct{}, 1),
}
}
// lock will prevent access to a model path
func (pac *proxyAccessControl) lock() {
pac.PathLock <- struct{}{}
pac.setStart(time.Now())
}
// unlock will release control of a model path
func (pac *proxyAccessControl) unlock() {
<-pac.PathLock
pac.setStop(time.Now())
GetProfiling().AddToInMemoryLockTime(pac.getStop().Sub(pac.getStart()).Seconds())
}
// getStart is used for profiling purposes and returns the time at which access control was applied
func (pac *proxyAccessControl) getStart() time.Time {
pac.Lock()
defer pac.Unlock()
return pac.start
}
// getStart is used for profiling purposes and returns the time at which access control was removed
func (pac *proxyAccessControl) getStop() time.Time {
pac.Lock()
defer pac.Unlock()
return pac.stop
}
// getPath returns the access controlled path
func (pac *proxyAccessControl) getPath() string {
pac.Lock()
defer pac.Unlock()
return pac.Path
}
// getProxy returns the proxy used to reach a specific location in the data model
func (pac *proxyAccessControl) getProxy() *Proxy {
pac.Lock()
defer pac.Unlock()
return pac.Proxy
}
// setStart is for profiling purposes and applies a start time value at which access control was started
func (pac *proxyAccessControl) setStart(time time.Time) {
pac.Lock()
defer pac.Unlock()
pac.start = time
}
// setStop is for profiling purposes and applies a stop time value at which access control was stopped
func (pac *proxyAccessControl) setStop(time time.Time) {
pac.Lock()
defer pac.Unlock()
pac.stop = time
}
// SetProxy is used to changed the proxy object of an access controlled path
func (pac *proxyAccessControl) SetProxy(proxy *Proxy) {
pac.Lock()
defer pac.Unlock()
pac.Proxy = proxy
}
// Get retrieves data linked to a data model path
func (pac *proxyAccessControl) Get(path string, depth int, deep bool, txid string, control bool) interface{} {
if control {
pac.lock()
defer pac.unlock()
log.Debugf("controlling get, stack = %s", string(debug.Stack()))
}
// FIXME: Forcing depth to 0 for now due to problems deep copying the data structure
// The data traversal through reflection currently corrupts the content
return pac.getProxy().GetRoot().Get(path, "", 0, deep, txid)
}
// Update changes the content of the data model at the specified location with the provided data
func (pac *proxyAccessControl) Update(path string, data interface{}, strict bool, txid string, control bool) interface{} {
if control {
pac.lock()
defer pac.unlock()
log.Debugf("controlling update, stack = %s", string(debug.Stack()))
}
return pac.getProxy().GetRoot().Update(path, data, strict, txid, nil).GetData()
}
// Add creates a new data model entry at the specified location with the provided data
func (pac *proxyAccessControl) Add(path string, data interface{}, txid string, control bool) interface{} {
if control {
pac.lock()
defer pac.unlock()
log.Debugf("controlling add, stack = %s", string(debug.Stack()))
}
return pac.getProxy().GetRoot().Add(path, data, txid, nil).GetData()
}
// Remove discards information linked to the data model path
func (pac *proxyAccessControl) Remove(path string, txid string, control bool) interface{} {
if control {
pac.lock()
defer pac.unlock()
log.Debugf("controlling remove, stack = %s", string(debug.Stack()))
}
return pac.getProxy().GetRoot().Remove(path, txid, nil)
}