minio/cmd/notification.go
Harshavardhana ef61b36c5a Fix PUT bucket notification deadlocks (#5734)
This PR fixes two different variant of deadlocks in
notification.

- holding write lock on the bucket competing with read lock
- holding competing locks on read/save notification config
2018-03-29 12:00:20 -07:00

620 lines
18 KiB
Go

/*
* Minio Cloud Storage, (C) 2018 Minio, Inc.
*
* 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 cmd
import (
"bytes"
"context"
"encoding/json"
"encoding/xml"
"fmt"
"net/url"
"path"
"sync"
xerrors "github.com/minio/minio/pkg/errors"
"github.com/minio/minio/pkg/event"
"github.com/minio/minio/pkg/hash"
xnet "github.com/minio/minio/pkg/net"
)
// NotificationSys - notification system.
type NotificationSys struct {
sync.RWMutex
targetList *event.TargetList
bucketRulesMap map[string]event.RulesMap
bucketRemoteTargetRulesMap map[string]map[event.TargetID]event.RulesMap
peerRPCClientMap map[xnet.Host]*PeerRPCClient
}
// GetARNList - returns available ARNs.
func (sys *NotificationSys) GetARNList() []string {
arns := []string{}
region := globalServerConfig.GetRegion()
for _, targetID := range sys.targetList.List() {
arns = append(arns, targetID.ToARN(region).String())
}
return arns
}
// GetPeerRPCClient - returns PeerRPCClient of addr.
func (sys *NotificationSys) GetPeerRPCClient(addr xnet.Host) *PeerRPCClient {
return sys.peerRPCClientMap[addr]
}
// DeleteBucket - calls DeleteBucket RPC call on all peers.
func (sys *NotificationSys) DeleteBucket(bucketName string) map[xnet.Host]error {
errors := make(map[xnet.Host]error)
var wg sync.WaitGroup
for addr, client := range sys.peerRPCClientMap {
wg.Add(1)
go func(addr xnet.Host, client *PeerRPCClient) {
defer wg.Done()
if err := client.DeleteBucket(bucketName); err != nil {
errors[addr] = err
}
}(addr, client)
}
wg.Wait()
return errors
}
// UpdateBucketPolicy - calls UpdateBucketPolicy RPC call on all peers.
func (sys *NotificationSys) UpdateBucketPolicy(bucketName string) map[xnet.Host]error {
errors := make(map[xnet.Host]error)
var wg sync.WaitGroup
for addr, client := range sys.peerRPCClientMap {
wg.Add(1)
go func(addr xnet.Host, client *PeerRPCClient) {
defer wg.Done()
if err := client.UpdateBucketPolicy(bucketName); err != nil {
errors[addr] = err
}
}(addr, client)
}
wg.Wait()
return errors
}
// PutBucketNotification - calls PutBucketNotification RPC call on all peers.
func (sys *NotificationSys) PutBucketNotification(bucketName string, rulesMap event.RulesMap) map[xnet.Host]error {
errors := make(map[xnet.Host]error)
var wg sync.WaitGroup
for addr, client := range sys.peerRPCClientMap {
wg.Add(1)
go func(addr xnet.Host, client *PeerRPCClient, rulesMap event.RulesMap) {
defer wg.Done()
if err := client.PutBucketNotification(bucketName, rulesMap); err != nil {
errors[addr] = err
}
}(addr, client, rulesMap.Clone())
}
wg.Wait()
return errors
}
// ListenBucketNotification - calls ListenBucketNotification RPC call on all peers.
func (sys *NotificationSys) ListenBucketNotification(bucketName string, eventNames []event.Name, pattern string, targetID event.TargetID, localPeer xnet.Host) map[xnet.Host]error {
errors := make(map[xnet.Host]error)
var wg sync.WaitGroup
for addr, client := range sys.peerRPCClientMap {
wg.Add(1)
go func(addr xnet.Host, client *PeerRPCClient) {
defer wg.Done()
if err := client.ListenBucketNotification(bucketName, eventNames, pattern, targetID, localPeer); err != nil {
errors[addr] = err
}
}(addr, client)
}
wg.Wait()
return errors
}
// AddRemoteTarget - adds event rules map, HTTP/PeerRPC client target to bucket name.
func (sys *NotificationSys) AddRemoteTarget(bucketName string, target event.Target, rulesMap event.RulesMap) error {
if err := sys.targetList.Add(target); err != nil {
return err
}
sys.Lock()
targetMap := sys.bucketRemoteTargetRulesMap[bucketName]
if targetMap == nil {
targetMap = make(map[event.TargetID]event.RulesMap)
}
targetMap[target.ID()] = rulesMap.Clone()
sys.bucketRemoteTargetRulesMap[bucketName] = targetMap
sys.Unlock()
sys.AddRulesMap(bucketName, rulesMap)
return nil
}
// RemoteTargetExist - checks whether given target ID is a HTTP/PeerRPC client target or not.
func (sys *NotificationSys) RemoteTargetExist(bucketName string, targetID event.TargetID) bool {
sys.Lock()
defer sys.Unlock()
targetMap, ok := sys.bucketRemoteTargetRulesMap[bucketName]
if ok {
_, ok = targetMap[targetID]
}
return ok
}
// initListeners - initializes PeerRPC clients available in listener.json.
func (sys *NotificationSys) initListeners(objAPI ObjectLayer, bucketName string) error {
// listener.json is available/applicable only in DistXL mode.
if !globalIsDistXL {
return nil
}
// Construct path to listener.json for the given bucket.
configFile := path.Join(bucketConfigPrefix, bucketName, bucketListenerConfig)
transactionConfigFile := configFile + ".transaction"
// As object layer's GetObject() and PutObject() take respective lock on minioMetaBucket
// and configFile, take a transaction lock to avoid data race between readConfig()
// and saveConfig().
objLock := globalNSMutex.NewNSLock(minioMetaBucket, transactionConfigFile)
if err := objLock.GetLock(globalOperationTimeout); err != nil {
return err
}
defer objLock.Unlock()
reader, err := readConfig(objAPI, configFile)
if err != nil && !xerrors.IsErrIgnored(err, errDiskNotFound, errNoSuchNotifications) {
return err
}
listenerList := []ListenBucketNotificationArgs{}
if reader != nil {
if err = json.NewDecoder(reader).Decode(&listenerList); err != nil {
errorIf(err, "Unable to parse listener.json.")
return xerrors.Trace(err)
}
}
if len(listenerList) == 0 {
// Nothing to initialize for empty listener list.
return nil
}
activeListenerList := []ListenBucketNotificationArgs{}
for _, args := range listenerList {
var found bool
if found, err = isLocalHost(args.Addr.Name); err != nil {
errorIf(err, "unable to check address %v is local host", args.Addr)
return err
}
if found {
// As this function is called at startup, skip HTTP listener to this host.
continue
}
rpcClient := sys.GetPeerRPCClient(args.Addr)
if rpcClient == nil {
return fmt.Errorf("unable to find PeerRPCClient by address %v in listener.json for bucket %v", args.Addr, bucketName)
}
var exist bool
if exist, err = rpcClient.RemoteTargetExist(bucketName, args.TargetID); err != nil {
return err
}
if !exist {
// Skip previously connected HTTP listener which is not found in remote peer.
continue
}
target := NewPeerRPCClientTarget(bucketName, args.TargetID, rpcClient)
rulesMap := event.NewRulesMap(args.EventNames, args.Pattern, target.ID())
if err = sys.AddRemoteTarget(bucketName, target, rulesMap); err != nil {
return err
}
activeListenerList = append(activeListenerList, args)
}
data, err := json.Marshal(activeListenerList)
if err != nil {
return err
}
return saveConfig(objAPI, configFile, data)
}
// Init - initializes notification system from notification.xml and listener.json of all buckets.
func (sys *NotificationSys) Init(objAPI ObjectLayer) error {
if objAPI == nil {
return errInvalidArgument
}
buckets, err := objAPI.ListBuckets(context.Background())
if err != nil {
return err
}
for _, bucket := range buckets {
config, err := readNotificationConfig(objAPI, bucket.Name)
if err != nil {
if !xerrors.IsErrIgnored(err, errDiskNotFound, errNoSuchNotifications) {
errorIf(err, "Unable to load notification configuration of bucket %v", bucket.Name)
return err
}
} else {
sys.AddRulesMap(bucket.Name, config.ToRulesMap())
}
if err = sys.initListeners(objAPI, bucket.Name); err != nil {
errorIf(err, "Unable to initialize HTTP listener for bucket %v", bucket.Name)
return err
}
}
return nil
}
// AddRulesMap - adds rules map for bucket name.
func (sys *NotificationSys) AddRulesMap(bucketName string, rulesMap event.RulesMap) {
sys.Lock()
defer sys.Unlock()
rulesMap = rulesMap.Clone()
for _, targetRulesMap := range sys.bucketRemoteTargetRulesMap[bucketName] {
rulesMap.Add(targetRulesMap)
}
rulesMap.Add(sys.bucketRulesMap[bucketName])
sys.bucketRulesMap[bucketName] = rulesMap
}
// RemoveRulesMap - removes rules map for bucket name.
func (sys *NotificationSys) RemoveRulesMap(bucketName string, rulesMap event.RulesMap) {
sys.Lock()
defer sys.Unlock()
sys.bucketRulesMap[bucketName].Remove(rulesMap)
if len(sys.bucketRulesMap[bucketName]) == 0 {
delete(sys.bucketRulesMap, bucketName)
}
}
// RemoveNotification - removes all notification configuration for bucket name.
func (sys *NotificationSys) RemoveNotification(bucketName string) {
sys.Lock()
defer sys.Unlock()
delete(sys.bucketRulesMap, bucketName)
for targetID := range sys.bucketRemoteTargetRulesMap[bucketName] {
sys.targetList.Remove(targetID)
delete(sys.bucketRemoteTargetRulesMap[bucketName], targetID)
}
delete(sys.bucketRemoteTargetRulesMap, bucketName)
}
// RemoveAllRemoteTargets - closes and removes all HTTP/PeerRPC client targets.
func (sys *NotificationSys) RemoveAllRemoteTargets() {
for _, targetMap := range sys.bucketRemoteTargetRulesMap {
for targetID := range targetMap {
sys.targetList.Remove(targetID)
}
}
}
// RemoveRemoteTarget - closes and removes target by target ID.
func (sys *NotificationSys) RemoveRemoteTarget(bucketName string, targetID event.TargetID) {
for id, err := range sys.targetList.Remove(targetID) {
errorIf(err, "unable to close target ID %v", id)
}
sys.Lock()
defer sys.Unlock()
if _, ok := sys.bucketRemoteTargetRulesMap[bucketName]; ok {
delete(sys.bucketRemoteTargetRulesMap[bucketName], targetID)
if len(sys.bucketRemoteTargetRulesMap[bucketName]) == 0 {
delete(sys.bucketRemoteTargetRulesMap, bucketName)
}
}
}
func (sys *NotificationSys) send(bucketName string, eventData event.Event, targetIDs ...event.TargetID) map[event.TargetID]error {
errMap := sys.targetList.Send(eventData, targetIDs...)
for targetID := range errMap {
if sys.RemoteTargetExist(bucketName, targetID) {
sys.RemoveRemoteTarget(bucketName, targetID)
}
}
return errMap
}
// Send - sends event data to all matching targets.
func (sys *NotificationSys) Send(args eventArgs) map[event.TargetID]error {
sys.RLock()
targetIDSet := sys.bucketRulesMap[args.BucketName].Match(args.EventName, args.Object.Name)
sys.RUnlock()
if len(targetIDSet) == 0 {
return nil
}
targetIDs := targetIDSet.ToSlice()
return sys.send(args.BucketName, args.ToEvent(), targetIDs...)
}
// NewNotificationSys - creates new notification system object.
func NewNotificationSys(config *serverConfig, endpoints EndpointList) (*NotificationSys, error) {
targetList, err := getNotificationTargets(config)
if err != nil {
return nil, err
}
peerRPCClientMap := makeRemoteRPCClients(endpoints)
// bucketRulesMap/bucketRemoteTargetRulesMap are initialized by NotificationSys.Init()
return &NotificationSys{
targetList: targetList,
bucketRulesMap: make(map[string]event.RulesMap),
bucketRemoteTargetRulesMap: make(map[string]map[event.TargetID]event.RulesMap),
peerRPCClientMap: peerRPCClientMap,
}, nil
}
type eventArgs struct {
EventName event.Name
BucketName string
Object ObjectInfo
ReqParams map[string]string
Host string
Port string
UserAgent string
}
// ToEvent - converts to notification event.
func (args eventArgs) ToEvent() event.Event {
getOriginEndpoint := func() string {
host := globalMinioHost
if host == "" {
// FIXME: Send FQDN or hostname of this machine than sending IP address.
host = localIP4.ToSlice()[0]
}
return fmt.Sprintf("%s://%s:%s", getURLScheme(globalIsSSL), host, globalMinioPort)
}
creds := globalServerConfig.GetCredential()
eventTime := UTCNow()
uniqueID := fmt.Sprintf("%X", eventTime.UnixNano())
newEvent := event.Event{
EventVersion: "2.0",
EventSource: "minio:s3",
AwsRegion: globalServerConfig.GetRegion(),
EventTime: eventTime.Format(event.AMZTimeFormat),
EventName: args.EventName,
UserIdentity: event.Identity{creds.AccessKey},
RequestParameters: args.ReqParams,
ResponseElements: map[string]string{
"x-amz-request-id": uniqueID,
"x-minio-origin-endpoint": getOriginEndpoint(), // Minio specific custom elements.
},
S3: event.Metadata{
SchemaVersion: "1.0",
ConfigurationID: "Config",
Bucket: event.Bucket{
Name: args.BucketName,
OwnerIdentity: event.Identity{creds.AccessKey},
ARN: bucketARNPrefix + args.BucketName,
},
Object: event.Object{
Key: url.QueryEscape(args.Object.Name),
VersionID: "1",
Sequencer: uniqueID,
},
},
Source: event.Source{
Host: args.Host,
Port: args.Port,
UserAgent: args.UserAgent,
},
}
if args.EventName != event.ObjectRemovedDelete {
newEvent.S3.Object.ETag = args.Object.ETag
newEvent.S3.Object.Size = args.Object.Size
newEvent.S3.Object.ContentType = args.Object.ContentType
newEvent.S3.Object.UserMetadata = args.Object.UserDefined
}
return newEvent
}
func sendEvent(args eventArgs) {
// globalNotificationSys is not initialized in gateway mode.
if globalNotificationSys == nil {
return
}
for targetID, err := range globalNotificationSys.Send(args) {
errorIf(err, "unable to send event %v of bucket: %v, object: %v to target %v",
args.EventName, args.BucketName, args.Object.Name, targetID)
}
}
func saveConfig(objAPI ObjectLayer, configFile string, data []byte) error {
hashReader, err := hash.NewReader(bytes.NewReader(data), int64(len(data)), "", getSHA256Hash(data))
if err != nil {
return err
}
_, err = objAPI.PutObject(context.Background(), minioMetaBucket, configFile, hashReader, nil)
return err
}
func readConfig(objAPI ObjectLayer, configFile string) (*bytes.Buffer, error) {
var buffer bytes.Buffer
// Read entire content by setting size to -1
err := objAPI.GetObject(context.Background(), minioMetaBucket, configFile, 0, -1, &buffer, "")
if err != nil {
// Ignore if err is ObjectNotFound or IncompleteBody when bucket is not configured with notification
if isErrObjectNotFound(err) || isErrIncompleteBody(err) {
return nil, xerrors.Trace(errNoSuchNotifications)
}
errorIf(err, "Unable to read file %v", configFile)
return nil, err
}
// Return NoSuchNotifications on empty content.
if buffer.Len() == 0 {
return nil, xerrors.Trace(errNoSuchNotifications)
}
return &buffer, nil
}
func readNotificationConfig(objAPI ObjectLayer, bucketName string) (*event.Config, error) {
// Construct path to notification.xml for the given bucket.
configFile := path.Join(bucketConfigPrefix, bucketName, bucketNotificationConfig)
reader, err := readConfig(objAPI, configFile)
if err != nil {
return nil, err
}
return event.ParseConfig(reader, globalServerConfig.GetRegion(), globalNotificationSys.targetList)
}
func saveNotificationConfig(objAPI ObjectLayer, bucketName string, config *event.Config) error {
data, err := xml.Marshal(config)
if err != nil {
return err
}
configFile := path.Join(bucketConfigPrefix, bucketName, bucketNotificationConfig)
return saveConfig(objAPI, configFile, data)
}
// SaveListener - saves HTTP client currently listening for events to listener.json.
func SaveListener(objAPI ObjectLayer, bucketName string, eventNames []event.Name, pattern string, targetID event.TargetID, addr xnet.Host) error {
// listener.json is available/applicable only in DistXL mode.
if !globalIsDistXL {
return nil
}
// Construct path to listener.json for the given bucket.
configFile := path.Join(bucketConfigPrefix, bucketName, bucketListenerConfig)
transactionConfigFile := configFile + ".transaction"
// As object layer's GetObject() and PutObject() take respective lock on minioMetaBucket
// and configFile, take a transaction lock to avoid data race between readConfig()
// and saveConfig().
objLock := globalNSMutex.NewNSLock(minioMetaBucket, transactionConfigFile)
if err := objLock.GetLock(globalOperationTimeout); err != nil {
return err
}
defer objLock.Unlock()
reader, err := readConfig(objAPI, configFile)
if err != nil && !xerrors.IsErrIgnored(err, errDiskNotFound, errNoSuchNotifications) {
return err
}
listenerList := []ListenBucketNotificationArgs{}
if reader != nil {
if err = json.NewDecoder(reader).Decode(&listenerList); err != nil {
errorIf(err, "Unable to parse listener.json.")
return xerrors.Trace(err)
}
}
listenerList = append(listenerList, ListenBucketNotificationArgs{
EventNames: eventNames,
Pattern: pattern,
TargetID: targetID,
Addr: addr,
})
data, err := json.Marshal(listenerList)
if err != nil {
return err
}
return saveConfig(objAPI, configFile, data)
}
// RemoveListener - removes HTTP client currently listening for events from listener.json.
func RemoveListener(objAPI ObjectLayer, bucketName string, targetID event.TargetID, addr xnet.Host) error {
// listener.json is available/applicable only in DistXL mode.
if !globalIsDistXL {
return nil
}
// Construct path to listener.json for the given bucket.
configFile := path.Join(bucketConfigPrefix, bucketName, bucketListenerConfig)
transactionConfigFile := configFile + ".transaction"
// As object layer's GetObject() and PutObject() take respective lock on minioMetaBucket
// and configFile, take a transaction lock to avoid data race between readConfig()
// and saveConfig().
objLock := globalNSMutex.NewNSLock(minioMetaBucket, transactionConfigFile)
if err := objLock.GetLock(globalOperationTimeout); err != nil {
return err
}
defer objLock.Unlock()
reader, err := readConfig(objAPI, configFile)
if err != nil && !xerrors.IsErrIgnored(err, errDiskNotFound, errNoSuchNotifications) {
return err
}
listenerList := []ListenBucketNotificationArgs{}
if reader != nil {
if err = json.NewDecoder(reader).Decode(&listenerList); err != nil {
errorIf(err, "Unable to parse listener.json.")
return xerrors.Trace(err)
}
}
if len(listenerList) == 0 {
// Nothing to remove.
return nil
}
activeListenerList := []ListenBucketNotificationArgs{}
for _, args := range listenerList {
if args.TargetID == targetID && args.Addr.Equal(addr) {
// Skip if matches
continue
}
activeListenerList = append(activeListenerList, args)
}
data, err := json.Marshal(activeListenerList)
if err != nil {
return err
}
return saveConfig(objAPI, configFile, data)
}