api: Implement bucket notification. (#2271)

* Implement basic S3 notifications through queues

Supports multiple queues and three basic queue types:

1. NilQueue -- messages don't get sent anywhere
2. LogQueue -- messages get logged
3. AmqpQueue -- messages are sent to an AMQP queue

* api: Implement bucket notification.

Supports two different queue types

- AMQP
- ElasticSearch.

* Add support for redis

vendor/gopkg.in/olivere/elastic.v3/indices_refresh.go

@@ -0,0 +1,93 @@
+// Copyright 2012-2015 Oliver Eilhard. All rights reserved.
+// Use of this source code is governed by a MIT-license.
+// See http://olivere.mit-license.org/license.txt for details.
+
+package elastic
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+
+	"gopkg.in/olivere/elastic.v3/uritemplates"
+)
+
+type RefreshService struct {
+	client  *Client
+	indices []string
+	force   *bool
+	pretty  bool
+}
+
+func NewRefreshService(client *Client) *RefreshService {
+	builder := &RefreshService{
+		client:  client,
+		indices: make([]string, 0),
+	}
+	return builder
+}
+
+func (s *RefreshService) Index(indices ...string) *RefreshService {
+	s.indices = append(s.indices, indices...)
+	return s
+}
+
+func (s *RefreshService) Force(force bool) *RefreshService {
+	s.force = &force
+	return s
+}
+
+func (s *RefreshService) Pretty(pretty bool) *RefreshService {
+	s.pretty = pretty
+	return s
+}
+
+func (s *RefreshService) Do() (*RefreshResult, error) {
+	// Build url
+	path := "/"
+
+	// Indices part
+	indexPart := make([]string, 0)
+	for _, index := range s.indices {
+		index, err := uritemplates.Expand("{index}", map[string]string{
+			"index": index,
+		})
+		if err != nil {
+			return nil, err
+		}
+		indexPart = append(indexPart, index)
+	}
+	if len(indexPart) > 0 {
+		path += strings.Join(indexPart, ",")
+	}
+
+	path += "/_refresh"
+
+	// Parameters
+	params := make(url.Values)
+	if s.force != nil {
+		params.Set("force", fmt.Sprintf("%v", *s.force))
+	}
+	if s.pretty {
+		params.Set("pretty", fmt.Sprintf("%v", s.pretty))
+	}
+
+	// Get response
+	res, err := s.client.PerformRequest("POST", path, params, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	// Return result
+	ret := new(RefreshResult)
+	if err := s.client.decoder.Decode(res.Body, ret); err != nil {
+		return nil, err
+	}
+	return ret, nil
+}
+
+// -- Result of a refresh request.
+
+type RefreshResult struct {
+	Shards shardsInfo `json:"_shards,omitempty"`
+}