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/search_queries_geo_distance.go

@@ -0,0 +1,116 @@
+// 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
+
+// GeoDistanceQuery filters documents that include only hits that exists
+// within a specific distance from a geo point.
+//
+// For more details, see:
+// https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-geo-distance-query.html
+type GeoDistanceQuery struct {
+	name         string
+	distance     string
+	lat          float64
+	lon          float64
+	geohash      string
+	distanceType string
+	optimizeBbox string
+	queryName    string
+}
+
+// NewGeoDistanceQuery creates and initializes a new GeoDistanceQuery.
+func NewGeoDistanceQuery(name string) *GeoDistanceQuery {
+	return &GeoDistanceQuery{name: name}
+}
+
+func (q *GeoDistanceQuery) GeoPoint(point *GeoPoint) *GeoDistanceQuery {
+	q.lat = point.Lat
+	q.lon = point.Lon
+	return q
+}
+
+func (q *GeoDistanceQuery) Point(lat, lon float64) *GeoDistanceQuery {
+	q.lat = lat
+	q.lon = lon
+	return q
+}
+
+func (q *GeoDistanceQuery) Lat(lat float64) *GeoDistanceQuery {
+	q.lat = lat
+	return q
+}
+
+func (q *GeoDistanceQuery) Lon(lon float64) *GeoDistanceQuery {
+	q.lon = lon
+	return q
+}
+
+func (q *GeoDistanceQuery) GeoHash(geohash string) *GeoDistanceQuery {
+	q.geohash = geohash
+	return q
+}
+
+func (q *GeoDistanceQuery) Distance(distance string) *GeoDistanceQuery {
+	q.distance = distance
+	return q
+}
+
+func (q *GeoDistanceQuery) DistanceType(distanceType string) *GeoDistanceQuery {
+	q.distanceType = distanceType
+	return q
+}
+
+func (q *GeoDistanceQuery) OptimizeBbox(optimizeBbox string) *GeoDistanceQuery {
+	q.optimizeBbox = optimizeBbox
+	return q
+}
+
+func (q *GeoDistanceQuery) QueryName(queryName string) *GeoDistanceQuery {
+	q.queryName = queryName
+	return q
+}
+
+// Source returns JSON for the function score query.
+func (q *GeoDistanceQuery) Source() (interface{}, error) {
+	// {
+	//   "geo_distance" : {
+	//       "distance" : "200km",
+	//       "pin.location" : {
+	//           "lat" : 40,
+	//           "lon" : -70
+	//       }
+	//   }
+	// }
+
+	source := make(map[string]interface{})
+
+	params := make(map[string]interface{})
+
+	if q.geohash != "" {
+		params[q.name] = q.geohash
+	} else {
+		location := make(map[string]interface{})
+		location["lat"] = q.lat
+		location["lon"] = q.lon
+		params[q.name] = location
+	}
+
+	if q.distance != "" {
+		params["distance"] = q.distance
+	}
+	if q.distanceType != "" {
+		params["distance_type"] = q.distanceType
+	}
+	if q.optimizeBbox != "" {
+		params["optimize_bbox"] = q.optimizeBbox
+	}
+	if q.queryName != "" {
+		params["_name"] = q.queryName
+	}
+
+	source["geo_distance"] = params
+
+	return source, nil
+}