minio/pkg/event/target/elasticsearch.go

294 lines
8.3 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 target
import (
"context"
"fmt"
"net/http"
"net/url"
"os"
"path/filepath"
"strings"
"time"
"github.com/minio/minio/pkg/event"
xnet "github.com/minio/minio/pkg/net"
"github.com/pkg/errors"
"gopkg.in/olivere/elastic.v5"
)
// Elastic constants
const (
ElasticFormat = "format"
ElasticURL = "url"
ElasticIndex = "index"
ElasticQueueDir = "queue_dir"
ElasticQueueLimit = "queue_limit"
EnvElasticEnable = "MINIO_NOTIFY_ELASTICSEARCH_ENABLE"
EnvElasticFormat = "MINIO_NOTIFY_ELASTICSEARCH_FORMAT"
EnvElasticURL = "MINIO_NOTIFY_ELASTICSEARCH_URL"
EnvElasticIndex = "MINIO_NOTIFY_ELASTICSEARCH_INDEX"
EnvElasticQueueDir = "MINIO_NOTIFY_ELASTICSEARCH_QUEUE_DIR"
EnvElasticQueueLimit = "MINIO_NOTIFY_ELASTICSEARCH_QUEUE_LIMIT"
)
// ElasticsearchArgs - Elasticsearch target arguments.
type ElasticsearchArgs struct {
Enable bool `json:"enable"`
Format string `json:"format"`
URL xnet.URL `json:"url"`
Index string `json:"index"`
QueueDir string `json:"queueDir"`
QueueLimit uint64 `json:"queueLimit"`
}
// Validate ElasticsearchArgs fields
func (a ElasticsearchArgs) Validate() error {
if !a.Enable {
return nil
}
if a.URL.IsEmpty() {
return errors.New("empty URL")
}
if a.Format != "" {
f := strings.ToLower(a.Format)
if f != event.NamespaceFormat && f != event.AccessFormat {
return errors.New("format value unrecognized")
}
}
if a.Index == "" {
return errors.New("empty index value")
}
return nil
}
// ElasticsearchTarget - Elasticsearch target.
type ElasticsearchTarget struct {
id event.TargetID
args ElasticsearchArgs
client *elastic.Client
store Store
loggerOnce func(ctx context.Context, err error, id interface{}, errKind ...interface{})
}
// ID - returns target ID.
func (target *ElasticsearchTarget) ID() event.TargetID {
return target.id
}
// HasQueueStore - Checks if the queueStore has been configured for the target
func (target *ElasticsearchTarget) HasQueueStore() bool {
return target.store != nil
}
// IsActive - Return true if target is up and active
func (target *ElasticsearchTarget) IsActive() (bool, error) {
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
if target.client == nil {
client, err := newClient(target.args)
if err != nil {
return false, err
}
target.client = client
}
_, code, err := target.client.Ping(target.args.URL.String()).HttpHeadOnly(true).Do(ctx)
if err != nil {
if elastic.IsConnErr(err) || elastic.IsContextErr(err) || xnet.IsNetworkOrHostDown(err) {
return false, errNotConnected
}
return false, err
}
return !(code >= http.StatusBadRequest), nil
}
// Save - saves the events to the store if queuestore is configured, which will be replayed when the elasticsearch connection is active.
func (target *ElasticsearchTarget) Save(eventData event.Event) error {
if target.store != nil {
return target.store.Put(eventData)
}
err := target.send(eventData)
if elastic.IsConnErr(err) || elastic.IsContextErr(err) || xnet.IsNetworkOrHostDown(err) {
return errNotConnected
}
return err
}
// send - sends the event to the target.
func (target *ElasticsearchTarget) send(eventData event.Event) error {
var key string
exists := func() (bool, error) {
return target.client.Exists().Index(target.args.Index).Type("event").Id(key).Do(context.Background())
}
remove := func() error {
exists, err := exists()
if err == nil && exists {
_, err = target.client.Delete().Index(target.args.Index).Type("event").Id(key).Do(context.Background())
}
return err
}
update := func() error {
_, err := target.client.Index().Index(target.args.Index).Type("event").BodyJson(map[string]interface{}{"Records": []event.Event{eventData}}).Id(key).Do(context.Background())
return err
}
add := func() error {
_, err := target.client.Index().Index(target.args.Index).Type("event").BodyJson(map[string]interface{}{"Records": []event.Event{eventData}}).Do(context.Background())
return err
}
if target.args.Format == event.NamespaceFormat {
objectName, err := url.QueryUnescape(eventData.S3.Object.Key)
if err != nil {
return err
}
key = eventData.S3.Bucket.Name + "/" + objectName
if eventData.EventName == event.ObjectRemovedDelete {
err = remove()
} else {
err = update()
}
return err
}
if target.args.Format == event.AccessFormat {
return add()
}
return nil
}
// Send - reads an event from store and sends it to Elasticsearch.
func (target *ElasticsearchTarget) Send(eventKey string) error {
var err error
if target.client == nil {
target.client, err = newClient(target.args)
if err != nil {
return err
}
}
eventData, eErr := target.store.Get(eventKey)
if eErr != nil {
// The last event key in a successful batch will be sent in the channel atmost once by the replayEvents()
// Such events will not exist and wouldve been already been sent successfully.
if os.IsNotExist(eErr) {
return nil
}
return eErr
}
if err := target.send(eventData); err != nil {
if elastic.IsConnErr(err) || elastic.IsContextErr(err) || xnet.IsNetworkOrHostDown(err) {
return errNotConnected
}
return err
}
// Delete the event from store.
return target.store.Del(eventKey)
}
// Close - does nothing and available for interface compatibility.
func (target *ElasticsearchTarget) Close() error {
if target.client != nil {
// Stops the background processes that the client is running.
target.client.Stop()
}
return nil
}
// createIndex - creates the index if it does not exist.
func createIndex(client *elastic.Client, args ElasticsearchArgs) error {
exists, err := client.IndexExists(args.Index).Do(context.Background())
if err != nil {
return err
}
if !exists {
var createIndex *elastic.IndicesCreateResult
if createIndex, err = client.CreateIndex(args.Index).Do(context.Background()); err != nil {
return err
}
if !createIndex.Acknowledged {
return fmt.Errorf("index %v not created", args.Index)
}
}
return nil
}
// newClient - creates a new elastic client with args provided.
func newClient(args ElasticsearchArgs) (*elastic.Client, error) {
client, err := elastic.NewClient(elastic.SetURL(args.URL.String()), elastic.SetMaxRetries(10))
if err != nil {
// https://github.com/olivere/elastic/wiki/Connection-Errors
if elastic.IsConnErr(err) || elastic.IsContextErr(err) || xnet.IsNetworkOrHostDown(err) {
return nil, errNotConnected
}
return nil, err
}
if err = createIndex(client, args); err != nil {
return nil, err
}
return client, nil
}
// NewElasticsearchTarget - creates new Elasticsearch target.
func NewElasticsearchTarget(id string, args ElasticsearchArgs, doneCh <-chan struct{}, loggerOnce func(ctx context.Context, err error, id interface{}, kind ...interface{}), test bool) (*ElasticsearchTarget, error) {
target := &ElasticsearchTarget{
id: event.TargetID{ID: id, Name: "elasticsearch"},
args: args,
loggerOnce: loggerOnce,
}
if args.QueueDir != "" {
queueDir := filepath.Join(args.QueueDir, storePrefix+"-elasticsearch-"+id)
target.store = NewQueueStore(queueDir, args.QueueLimit)
if err := target.store.Open(); err != nil {
target.loggerOnce(context.Background(), err, target.ID())
return target, err
}
}
var err error
target.client, err = newClient(args)
if err != nil {
if target.store == nil || err != errNotConnected {
target.loggerOnce(context.Background(), err, target.ID())
return target, err
}
}
if target.store != nil && !test {
// Replays the events from the store.
eventKeyCh := replayEvents(target.store, doneCh, target.loggerOnce, target.ID())
// Start replaying events from the store.
go sendEvents(target, eventKeyCh, doneCh, target.loggerOnce)
}
return target, nil
}