move chunker type parsing into its own file in chunk

License: MIT
Signed-off-by: Jeromy <[email protected]>

core/commands/add.go

@@ -1,12 +1,9 @@
 package commands
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"path"
-	"strconv"
-	"strings"
 
 	"github.com/ipfs/go-ipfs/Godeps/_workspace/src/github.com/cheggaaa/pb"
 
@@ -275,55 +272,9 @@ type adder struct {
 	chunker  string
 }
 
-func getChunker(r io.Reader, chunker string) (chunk.Splitter, error) {
-	switch {
-	case chunker == "":
-		return chunk.NewSizeSplitter(r, chunk.DefaultBlockSize), nil
-	case strings.HasPrefix(chunker, "size-"):
-		sizeStr := strings.Split(chunker, "-")[1]
-		size, err := strconv.Atoi(sizeStr)
-		if err != nil {
-			return nil, err
-		}
-
-		return chunk.NewSizeSplitter(r, int64(size)), nil
-	case strings.HasPrefix(chunker, "rabin"):
-		parts := strings.Split(chunker, "-")
-		switch len(parts) {
-		case 1:
-			return chunk.NewRabin(r, uint64(chunk.DefaultBlockSize)), nil
-		case 2:
-			size, err := strconv.Atoi(parts[1])
-			if err != nil {
-				return nil, err
-			}
-			return chunk.NewRabin(r, uint64(size)), nil
-		case 4:
-			min, err := strconv.Atoi(parts[1])
-			if err != nil {
-				return nil, err
-			}
-			avg, err := strconv.Atoi(parts[2])
-			if err != nil {
-				return nil, err
-			}
-			max, err := strconv.Atoi(parts[3])
-			if err != nil {
-				return nil, err
-			}
-
-			return chunk.NewRabinMinMax(r, uint64(min), uint64(avg), uint64(max)), nil
-		default:
-			return nil, errors.New("incorrect format (expected 'rabin' 'rabin-[avg]' or 'rabin-[min]-[avg]-[max]'")
-		}
-	default:
-		return nil, fmt.Errorf("unrecognized chunker option: %s", chunker)
-	}
-}
-
 // Perform the actual add & pin locally, outputting results to reader
 func add(n *core.IpfsNode, reader io.Reader, useTrickle bool, chunker string) (*dag.Node, error) {
-	chnk, err := getChunker(reader, chunker)
+	chnk, err := chunk.FromString(reader, chunker)
 	if err != nil {
 		return nil, err
 	}

fuse/readonly/ipfs_test.go

@@ -36,7 +36,7 @@ func randObj(t *testing.T, nd *core.IpfsNode, size int64) (*dag.Node, []byte) {
 	buf := make([]byte, size)
 	u.NewTimeSeededRand().Read(buf)
 	read := bytes.NewReader(buf)
-	obj, err := importer.BuildTrickleDagFromReader(read, nd.DAG, chunk.DefaultSplitter, nil)
+	obj, err := importer.BuildTrickleDagFromReader(nd.DAG, chunk.DefaultSplitter(read), nil)
 	if err != nil {
 		t.Fatal(err)
 	}

importer/chunk/parse.go

@@ -0,0 +1,75 @@
+package chunk
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+)
+
+func FromString(r io.Reader, chunker string) (Splitter, error) {
+	switch {
+	case chunker == "" || chunker == "default":
+		return NewSizeSplitter(r, DefaultBlockSize), nil
+
+	case strings.HasPrefix(chunker, "size-"):
+		sizeStr := strings.Split(chunker, "-")[1]
+		size, err := strconv.Atoi(sizeStr)
+		if err != nil {
+			return nil, err
+		}
+		return NewSizeSplitter(r, int64(size)), nil
+
+	case strings.HasPrefix(chunker, "rabin"):
+		return parseRabinString(r, chunker)
+
+	default:
+		return nil, fmt.Errorf("unrecognized chunker option: %s", chunker)
+	}
+}
+
+func parseRabinString(r io.Reader, chunker string) (Splitter, error) {
+	parts := strings.Split(chunker, "-")
+	switch len(parts) {
+	case 1:
+		return NewRabin(r, uint64(DefaultBlockSize)), nil
+	case 2:
+		size, err := strconv.Atoi(parts[1])
+		if err != nil {
+			return nil, err
+		}
+		return NewRabin(r, uint64(size)), nil
+	case 4:
+		sub := strings.Split(parts[1], ":")
+		if len(sub) > 1 && sub[0] != "min" {
+			return nil, errors.New("first label must be min")
+		}
+		min, err := strconv.Atoi(sub[len(sub)-1])
+		if err != nil {
+			return nil, err
+		}
+
+		sub = strings.Split(parts[1], ":")
+		if len(sub) > 1 && sub[0] != "avg" {
+			return nil, errors.New("second label must be avg")
+		}
+		avg, err := strconv.Atoi(sub[len(sub)-1])
+		if err != nil {
+			return nil, err
+		}
+
+		sub = strings.Split(parts[1], ":")
+		if len(sub) > 1 && sub[0] != "max" {
+			return nil, errors.New("final label must be max")
+		}
+		max, err := strconv.Atoi(parts[3])
+		if err != nil {
+			return nil, err
+		}
+
+		return NewRabinMinMax(r, uint64(min), uint64(avg), uint64(max)), nil
+	default:
+		return nil, errors.New("incorrect format (expected 'rabin' 'rabin-[avg]' or 'rabin-[min]-[avg]-[max]'")
+	}
+}