Upgrade server dependencies, manage them with govendor

vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go

@@ -0,0 +1,115 @@
+//  Copyright (c) 2017 Couchbase, 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 searcher
+
+import (
+	"github.com/blevesearch/bleve/geo"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/numeric"
+	"github.com/blevesearch/bleve/search"
+)
+
+func NewGeoPointDistanceSearcher(indexReader index.IndexReader, centerLon,
+	centerLat, dist float64, field string, boost float64,
+	options search.SearcherOptions) (search.Searcher, error) {
+
+	// compute bounding box containing the circle
+	topLeftLon, topLeftLat, bottomRightLon, bottomRightLat :=
+		geo.ComputeBoundingBox(centerLon, centerLat, dist)
+
+	// build a searcher for the box
+	boxSearcher, err := boxSearcher(indexReader,
+		topLeftLon, topLeftLat, bottomRightLon, bottomRightLat,
+		field, boost, options)
+	if err != nil {
+		return nil, err
+	}
+
+	// wrap it in a filtering searcher which checks the actual distance
+	return NewFilteringSearcher(boxSearcher,
+		buildDistFilter(indexReader, field, centerLon, centerLat, dist)), nil
+}
+
+// boxSearcher builds a searcher for the described bounding box
+// if the desired box crosses the dateline, it is automatically split into
+// two boxes joined through a disjunction searcher
+func boxSearcher(indexReader index.IndexReader,
+	topLeftLon, topLeftLat, bottomRightLon, bottomRightLat float64,
+	field string, boost float64, options search.SearcherOptions) (
+	search.Searcher, error) {
+	if bottomRightLon < topLeftLon {
+		// cross date line, rewrite as two parts
+
+		leftSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+			-180, bottomRightLat, bottomRightLon, topLeftLat,
+			field, boost, options, false)
+		if err != nil {
+			return nil, err
+		}
+		rightSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+			topLeftLon, bottomRightLat, 180, topLeftLat, field, boost, options, false)
+		if err != nil {
+			_ = leftSearcher.Close()
+			return nil, err
+		}
+
+		boxSearcher, err := NewDisjunctionSearcher(indexReader,
+			[]search.Searcher{leftSearcher, rightSearcher}, 0, options)
+		if err != nil {
+			_ = leftSearcher.Close()
+			_ = rightSearcher.Close()
+			return nil, err
+		}
+		return boxSearcher, nil
+	}
+
+	// build geoboundinggox searcher for that bounding box
+	boxSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
+		topLeftLon, bottomRightLat, bottomRightLon, topLeftLat, field, boost,
+		options, false)
+	if err != nil {
+		return nil, err
+	}
+	return boxSearcher, nil
+}
+
+func buildDistFilter(indexReader index.IndexReader, field string,
+	centerLon, centerLat, maxDist float64) FilterFunc {
+	return func(d *search.DocumentMatch) bool {
+		var lon, lat float64
+		var found bool
+		err := indexReader.DocumentVisitFieldTerms(d.IndexInternalID,
+			[]string{field}, func(field string, term []byte) {
+				// only consider the values which are shifted 0
+				prefixCoded := numeric.PrefixCoded(term)
+				shift, err := prefixCoded.Shift()
+				if err == nil && shift == 0 {
+					i64, err := prefixCoded.Int64()
+					if err == nil {
+						lon = geo.MortonUnhashLon(uint64(i64))
+						lat = geo.MortonUnhashLat(uint64(i64))
+						found = true
+					}
+				}
+			})
+		if err == nil && found {
+			dist := geo.Haversin(lon, lat, centerLon, centerLat)
+			if dist <= maxDist/1000 {
+				return true
+			}
+		}
+		return false
+	}
+}