dpa implements ChunkStore interface, still half baked

bzz/dpa.go

@@ -47,11 +47,12 @@ type DPA struct {
 // but the size of the subtree encoded in the chunk
 // 0 if request, to be supplied by the dpa
 type Chunk struct {
-	Reader SectionReader // nil if request, to be supplied by dpa
-	Data   []byte        // nil if request, to be supplied by dpa
-	Size   int64         // size of the data covered by the subtree encoded in this chunk
-	Key    Key           // always
-	C      chan bool     // to signal data delivery by the dpa
+	Reader SectionReader  // nil if request, to be supplied by dpa
+	Data   []byte         // nil if request, to be supplied by dpa
+	Size   int64          // size of the data covered by the subtree encoded in this chunk
+	Key    Key            // always
+	C      chan bool      // to signal data delivery by the dpa
+	req    *requestStatus //
 }
 
 type ChunkStore interface {
@@ -111,13 +112,15 @@ func (self *DPA) Store(data SectionReader) (key Key, err error) {
 
 // DPA is itself a chunk store , to stores a chunk only
 // its integrity is checked ?
-func (self *DPA) Put(*Chunk) (err error) {
+func (self *DPA) Put(chunk *Chunk) {
+	// rely on storeC
 	return
 }
 
 // Get(chunk *Chunk) looks up a chunk in the local stores
 // This method is blocking until the chunk is retrieved so additional timeout is needed to wrap this call
-func (self *DPA) Get(*Chunk) (err error) {
+func (self *DPA) Get(key Key) (chunk *Chunk, err error) {
+	// rely on retrieveC
 	return
 }
 
@@ -150,9 +153,22 @@ func (self *DPA) retrieveLoop() {
 	LOOP:
 		for chunk := range self.retrieveC {
 			go func() {
-				for _, store := range self.Stores {
-					if _, err := store.Get(chunk.Key); err != nil { // no waiting/blocking here
+				for i, store := range self.Stores {
+					storedChunk, err := store.Get(chunk.Key)
+					if err == notFound {
+						dpaLogger.DebugDetailf("%v retrieving chunk %x: NOT FOUND", store, chunk.Key)
+						return
+					}
+					if err != nil {
 						dpaLogger.DebugDetailf("%v retrieving chunk %x: %v", store, chunk.Key, err)
+						return
+					}
+					chunk.Reader = NewChunkReaderFromBytes(storedChunk.Data)
+					chunk.Size = storedChunk.Size
+					close(chunk.C)
+					// if not in cache, cache it in memstore
+					if i > 0 {
+						self.Stores[0].Put(chunk)
 					}
 				}
 			}()