Move storage package under registry package

Signed-off-by: Stephen J Day <stephen.day@docker.com>

docs/storage/filewriter_test.go

@@ -0,0 +1,148 @@
+package storage
+
+import (
+	"bytes"
+	"crypto/rand"
+	"io"
+	"os"
+	"testing"
+
+	"github.com/docker/distribution/digest"
+	"github.com/docker/distribution/storagedriver/inmemory"
+)
+
+// TestSimpleWrite takes the fileWriter through common write operations
+// ensuring data integrity.
+func TestSimpleWrite(t *testing.T) {
+	content := make([]byte, 1<<20)
+	n, err := rand.Read(content)
+	if err != nil {
+		t.Fatalf("unexpected error building random data: %v", err)
+	}
+
+	if n != len(content) {
+		t.Fatalf("random read did't fill buffer")
+	}
+
+	dgst, err := digest.FromReader(bytes.NewReader(content))
+	if err != nil {
+		t.Fatalf("unexpected error digesting random content: %v", err)
+	}
+
+	driver := inmemory.New()
+	path := "/random"
+
+	fw, err := newFileWriter(driver, path)
+	if err != nil {
+		t.Fatalf("unexpected error creating fileWriter: %v", err)
+	}
+	defer fw.Close()
+
+	n, err = fw.Write(content)
+	if err != nil {
+		t.Fatalf("unexpected error writing content: %v", err)
+	}
+
+	if n != len(content) {
+		t.Fatalf("unexpected write length: %d != %d", n, len(content))
+	}
+
+	fr, err := newFileReader(driver, path)
+	if err != nil {
+		t.Fatalf("unexpected error creating fileReader: %v", err)
+	}
+	defer fr.Close()
+
+	verifier := digest.NewDigestVerifier(dgst)
+	io.Copy(verifier, fr)
+
+	if !verifier.Verified() {
+		t.Fatalf("unable to verify write data")
+	}
+
+	// Check the seek position is equal to the content length
+	end, err := fw.Seek(0, os.SEEK_END)
+	if err != nil {
+		t.Fatalf("unexpected error seeking: %v", err)
+	}
+
+	if end != int64(len(content)) {
+		t.Fatalf("write did not advance offset: %d != %d", end, len(content))
+	}
+
+	// Double the content, but use the WriteAt method
+	doubled := append(content, content...)
+	doubledgst, err := digest.FromReader(bytes.NewReader(doubled))
+	if err != nil {
+		t.Fatalf("unexpected error digesting doubled content: %v", err)
+	}
+
+	n, err = fw.WriteAt(content, end)
+	if err != nil {
+		t.Fatalf("unexpected error writing content at %d: %v", end, err)
+	}
+
+	if n != len(content) {
+		t.Fatalf("writeat was short: %d != %d", n, len(content))
+	}
+
+	fr, err = newFileReader(driver, path)
+	if err != nil {
+		t.Fatalf("unexpected error creating fileReader: %v", err)
+	}
+	defer fr.Close()
+
+	verifier = digest.NewDigestVerifier(doubledgst)
+	io.Copy(verifier, fr)
+
+	if !verifier.Verified() {
+		t.Fatalf("unable to verify write data")
+	}
+
+	// Check that WriteAt didn't update the offset.
+	end, err = fw.Seek(0, os.SEEK_END)
+	if err != nil {
+		t.Fatalf("unexpected error seeking: %v", err)
+	}
+
+	if end != int64(len(content)) {
+		t.Fatalf("write did not advance offset: %d != %d", end, len(content))
+	}
+
+	// Now, we copy from one path to another, running the data through the
+	// fileReader to fileWriter, rather than the driver.Move command to ensure
+	// everything is working correctly.
+	fr, err = newFileReader(driver, path)
+	if err != nil {
+		t.Fatalf("unexpected error creating fileReader: %v", err)
+	}
+	defer fr.Close()
+
+	fw, err = newFileWriter(driver, "/copied")
+	if err != nil {
+		t.Fatalf("unexpected error creating fileWriter: %v", err)
+	}
+	defer fw.Close()
+
+	nn, err := io.Copy(fw, fr)
+	if err != nil {
+		t.Fatalf("unexpected error copying data: %v", err)
+	}
+
+	if nn != int64(len(doubled)) {
+		t.Fatalf("unexpected copy length: %d != %d", nn, len(doubled))
+	}
+
+	fr, err = newFileReader(driver, "/copied")
+	if err != nil {
+		t.Fatalf("unexpected error creating fileReader: %v", err)
+	}
+	defer fr.Close()
+
+	verifier = digest.NewDigestVerifier(doubledgst)
+	io.Copy(verifier, fr)
+
+	if !verifier.Verified() {
+		t.Fatalf("unable to verify write data")
+	}
+}