give indexes names, make stats available via expvar by default

config.go

@@ -66,6 +66,8 @@ func init() {
 
 	bootDuration := time.Since(bootStart)
 	bleveExpVar.Add("bootDuration", int64(bootDuration))
+	indexStats = NewIndexStats()
+	bleveExpVar.Set("indexes", indexStats)
 }
 
 var logger = log.New(ioutil.Discard, "bleve", log.LstdFlags)

http/index_create.go

@@ -64,6 +64,7 @@ func (h *CreateIndexHandler) ServeHTTP(w http.ResponseWriter, req *http.Request)
 		showError(w, req, fmt.Sprintf("error creating index: %v", err), 500)
 		return
 	}
+	newIndex.SetName(indexName)
 	RegisterIndexName(indexName, newIndex)
 	rv := struct {
 		Status string `json:"status"`

http/registry.go

@@ -18,7 +18,6 @@ import (
 
 var indexNameMapping map[string]bleve.Index
 var indexNameMappingLock sync.RWMutex
-var indexStats = bleve.IndexStats{}
 
 func RegisterIndexName(name string, idx bleve.Index) {
 	indexNameMappingLock.Lock()
@@ -28,7 +27,6 @@ func RegisterIndexName(name string, idx bleve.Index) {
 		indexNameMapping = make(map[string]bleve.Index)
 	}
 	indexNameMapping[name] = idx
-	indexStats[name] = idx.Stats()
 }
 
 func UnregisterIndexByName(name string) bleve.Index {
@@ -42,7 +40,6 @@ func UnregisterIndexByName(name string) bleve.Index {
 	if rv != nil {
 		delete(indexNameMapping, name)
 	}
-	delete(indexStats, name)
 	return rv
 }
 
@@ -66,10 +63,6 @@ func IndexNames() []string {
 	return rv
 }
 
-func IndexStats() bleve.IndexStats {
-	return indexStats
-}
-
 func UpdateAlias(alias string, add, remove []string) error {
 	indexNameMappingLock.Lock()
 	defer indexNameMappingLock.Unlock()

index.go

@@ -188,6 +188,11 @@ type Index interface {
 	SetInternal(key, val []byte) error
 	DeleteInternal(key []byte) error
 
+	// Name returns the name of the index (by deault this is the path)
+	Name() string
+	// SetName lets you assign your own logical name to this index
+	SetName(string)
+
 	// Advanced returns the indexer and data store, exposing lower level
 	// methods to enumerate records and access data.
 	Advanced() (index.Index, store.KVStore, error)

index_alias_impl.go

@@ -21,6 +21,7 @@ import (
 )
 
 type indexAliasImpl struct {
+	name    string
 	indexes []Index
 	mutex   sync.RWMutex
 	open    bool
@@ -30,6 +31,7 @@ type indexAliasImpl struct {
 // Index objects.
 func NewIndexAlias(indexes ...Index) *indexAliasImpl {
 	return &indexAliasImpl{
+		name:    "alias",
 		indexes: indexes,
 		open:    true,
 	}
@@ -561,6 +563,14 @@ func (i *indexAliasImpl) NewBatch() *Batch {
 	return i.indexes[0].NewBatch()
 }
 
+func (i *indexAliasImpl) Name() string {
+	return i.name
+}
+
+func (i *indexAliasImpl) SetName(name string) {
+	i.name = name
+}
+
 type indexAliasImplFieldDict struct {
 	index     *indexAliasImpl
 	fieldDict index.FieldDict

index_alias_impl_test.go

@@ -683,6 +683,7 @@ func TestMultiSearchSecondPage(t *testing.T) {
 // corresponding operation result value has been
 // set, in which case that is returned instead
 type stubIndex struct {
+	name           string
 	err            error
 	searchResult   *SearchResult
 	documentResult *document.Document
@@ -788,3 +789,11 @@ func (i *stubIndex) Advanced() (index.Index, store.KVStore, error) {
 func (i *stubIndex) NewBatch() *Batch {
 	return &Batch{}
 }
+
+func (i *stubIndex) Name() string {
+	return i.name
+}
+
+func (i *stubIndex) SetName(name string) {
+	i.name = name
+}

index_impl.go

@@ -30,6 +30,7 @@ import (
 
 type indexImpl struct {
 	path  string
+	name  string
 	meta  *indexMeta
 	s     store.KVStore
 	i     index.Index
@@ -50,6 +51,7 @@ func indexStorePath(path string) string {
 func newMemIndex(indexType string, mapping *IndexMapping) (*indexImpl, error) {
 	rv := indexImpl{
 		path:  "",
+		name:  "mem",
 		m:     mapping,
 		meta:  newIndexMeta(indexType, gtreap.Name, nil),
 		stats: &IndexStat{},
@@ -86,6 +88,7 @@ func newMemIndex(indexType string, mapping *IndexMapping) (*indexImpl, error) {
 	rv.mutex.Lock()
 	defer rv.mutex.Unlock()
 	rv.open = true
+	indexStats.Register(&rv)
 	return &rv, nil
 }
 
@@ -106,6 +109,7 @@ func newIndexUsing(path string, mapping *IndexMapping, indexType string, kvstore
 
 	rv := indexImpl{
 		path:  path,
+		name:  path,
 		m:     mapping,
 		meta:  newIndexMeta(indexType, kvstore, kvconfig),
 		stats: &IndexStat{},
@@ -152,12 +156,14 @@ func newIndexUsing(path string, mapping *IndexMapping, indexType string, kvstore
 	rv.mutex.Lock()
 	defer rv.mutex.Unlock()
 	rv.open = true
+	indexStats.Register(&rv)
 	return &rv, nil
 }
 
 func openIndexUsing(path string, runtimeConfig map[string]interface{}) (rv *indexImpl, err error) {
 	rv = &indexImpl{
 		path:  path,
+		name:  path,
 		stats: &IndexStat{},
 	}
 
@@ -238,6 +244,7 @@ func openIndexUsing(path string, runtimeConfig map[string]interface{}) (rv *inde
 	}
 
 	rv.m = &im
+	indexStats.Register(rv)
 	return rv, err
 }
 
@@ -725,6 +732,16 @@ func (i *indexImpl) NewBatch() *Batch {
 	}
 }
 
+func (i *indexImpl) Name() string {
+	return i.name
+}
+
+func (i *indexImpl) SetName(name string) {
+	indexStats.UnRegister(i)
+	i.name = name
+	indexStats.Register(i)
+}
+
 type indexImplFieldDict struct {
 	index       *indexImpl
 	indexReader index.IndexReader

index_stats.go

@@ -11,6 +11,7 @@ package bleve
 
 import (
 	"encoding/json"
+	"sync"
 	"sync/atomic"
 )
 
@@ -28,12 +29,37 @@ func (is *IndexStat) MarshalJSON() ([]byte, error) {
 	return json.Marshal(m)
 }
 
-type IndexStats map[string]*IndexStat
+type IndexStats struct {
+	indexes map[string]*IndexStat
+	mutex   sync.RWMutex
+}
 
-func (i IndexStats) String() string {
-	bytes, err := json.Marshal(i)
+func NewIndexStats() *IndexStats {
+	return &IndexStats{
+		indexes: make(map[string]*IndexStat),
+	}
+}
+
+func (i *IndexStats) Register(index Index) {
+	i.mutex.Lock()
+	defer i.mutex.Unlock()
+	i.indexes[index.Name()] = index.Stats()
+}
+
+func (i *IndexStats) UnRegister(index Index) {
+	i.mutex.Lock()
+	defer i.mutex.Unlock()
+	delete(i.indexes, index.Name())
+}
+
+func (i *IndexStats) String() string {
+	i.mutex.RLock()
+	defer i.mutex.RUnlock()
+	bytes, err := json.Marshal(i.indexes)
 	if err != nil {
 		return "error marshaling stats"
 	}
 	return string(bytes)
 }
+
+var indexStats *IndexStats