fix race condition in weed/volume-cache.go, bump patch

cdn-origin.go

@@ -132,7 +132,7 @@ func main() {
 	log.Info("Attempting to listen on " + listenAddr)
 	server := &fasthttp.Server{
 		Handler:                       h,
-		Name:                          "whats-this/cdn-origin/0.1.0",
+		Name:                          "whats-this/cdn-origin/0.1.1",
 		ReadBufferSize:                1024 * 6, // 6 KB
 		ReadTimeout:                   time.Minute * 30,
 		WriteTimeout:                  time.Minute * 30,

weed/volume-cache.go

 package weed
 
+import "sync"
+
 // VolumeCache stores a volume ID => volume URL map used for caching volume lookup responses from the master of a
 // SeaweedFS cluster.
 type VolumeCache struct {
+	sync.RWMutex
 	volumeCache map[uint32][]string
 	next        map[uint32]int
 }
 
 // Add adds a volume ID => location URL slice mapping to the volume cache.
 func (v *VolumeCache) Add(id uint32, urls []string) {
+	v.Lock()
+	defer v.Unlock()
 	v.volumeCache[id] = urls
 	v.next[id] = 0
 }
 
 // Get returns all volume server URLs for a given volume ID.
 func (v *VolumeCache) Get(id uint32) []string {
+	v.RLock()
+	defer v.RUnlock()
 	vol, _ := v.volumeCache[id]
 	return vol
 }
 
 // GetNext returns the n+1th location URL for the given volume ID, n is tracked internally.
 func (v *VolumeCache) GetNext(id uint32) string {
+	v.RLock()
+	defer v.RUnlock()
 	vol, ok := v.volumeCache[id]
 	volLen := len(vol)
 	if !ok || volLen == 0 {
@@ -36,11 +45,15 @@ func (v *VolumeCache) GetNext(id uint32) string {
 
 // Remove removes a volume from the volume cache.
 func (v *VolumeCache) Remove(id uint32) {
+	v.Lock()
+	defer v.Unlock()
 	delete(v.volumeCache, id)
 }
 
 // Empty clears all data and returns the VolumeCache to it's initial state.
 func (v *VolumeCache) Empty() {
+	v.Lock()
+	defer v.Unlock()
 	v.volumeCache = map[uint32][]string{}
 	v.next = map[uint32]int{}
 }