Adds storage driver interface, tests, and two basic implementations

storagedriver/inmemory/inmemory.go

@@ -0,0 +1,147 @@
+package inmemory
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"regexp"
+	"strings"
+	"sync"
+
+	"github.com/docker/docker-registry/storagedriver"
+)
+
+type InMemoryDriver struct {
+	storage map[string][]byte
+	mutex   sync.RWMutex
+}
+
+func NewDriver() *InMemoryDriver {
+	return &InMemoryDriver{storage: make(map[string][]byte)}
+}
+
+func (d *InMemoryDriver) GetContent(path string) ([]byte, error) {
+	d.mutex.RLock()
+	defer d.mutex.RUnlock()
+	contents, ok := d.storage[path]
+	if !ok {
+		return nil, storagedriver.PathNotFoundError{path}
+	}
+	return contents, nil
+}
+
+func (d *InMemoryDriver) PutContent(path string, contents []byte) error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+	d.storage[path] = contents
+	return nil
+}
+
+func (d *InMemoryDriver) ReadStream(path string, offset uint64) (io.ReadCloser, error) {
+	d.mutex.RLock()
+	defer d.mutex.RUnlock()
+	contents, err := d.GetContent(path)
+	if err != nil {
+		return nil, err
+	} else if len(contents) < int(offset) {
+		return nil, storagedriver.InvalidOffsetError{path, offset}
+	}
+
+	src := contents[offset:]
+	buf := make([]byte, len(src))
+	copy(buf, src)
+	return ioutil.NopCloser(bytes.NewReader(buf)), nil
+}
+
+func (d *InMemoryDriver) WriteStream(path string, offset, size uint64, reader io.ReadCloser) error {
+	defer reader.Close()
+	d.mutex.RLock()
+	defer d.mutex.RUnlock()
+
+	resumableOffset, err := d.ResumeWritePosition(path)
+	if err != nil {
+		return err
+	}
+
+	if offset > resumableOffset {
+		return storagedriver.InvalidOffsetError{path, offset}
+	}
+
+	contents, err := ioutil.ReadAll(reader)
+	if err != nil {
+		return err
+	}
+
+	if offset > 0 {
+		contents = append(d.storage[path][0:offset], contents...)
+	}
+
+	d.storage[path] = contents
+	return nil
+}
+
+func (d *InMemoryDriver) ResumeWritePosition(path string) (uint64, error) {
+	d.mutex.RLock()
+	defer d.mutex.RUnlock()
+	contents, ok := d.storage[path]
+	if !ok {
+		return 0, nil
+	}
+	return uint64(len(contents)), nil
+}
+
+func (d *InMemoryDriver) List(prefix string) ([]string, error) {
+	subPathMatcher, err := regexp.Compile(fmt.Sprintf("^%s/[^/]+", prefix))
+	if err != nil {
+		return nil, err
+	}
+
+	d.mutex.RLock()
+	defer d.mutex.RUnlock()
+	// we use map to collect uniq keys
+	keySet := make(map[string]struct{})
+	for k := range d.storage {
+		if key := subPathMatcher.FindString(k); key != "" {
+			keySet[key] = struct{}{}
+		}
+	}
+
+	keys := make([]string, 0, len(keySet))
+	for k := range keySet {
+		keys = append(keys, k)
+	}
+	return keys, nil
+}
+
+func (d *InMemoryDriver) Move(sourcePath string, destPath string) error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+	contents, ok := d.storage[sourcePath]
+	if !ok {
+		return storagedriver.PathNotFoundError{sourcePath}
+	}
+	d.storage[destPath] = contents
+	delete(d.storage, sourcePath)
+	return nil
+}
+
+func (d *InMemoryDriver) Delete(path string) error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+	subPaths := make([]string, 0)
+	for k := range d.storage {
+		if strings.HasPrefix(k, path) {
+			subPaths = append(subPaths, k)
+		}
+	}
+
+	if len(subPaths) == 0 {
+		return storagedriver.PathNotFoundError{path}
+	}
+
+	for _, subPath := range subPaths {
+		delete(d.storage, subPath)
+	}
+	return nil
+}

storagedriver/inmemory/inmemory_test.go

@@ -0,0 +1,20 @@
+package inmemory
+
+import (
+	"testing"
+
+	"github.com/docker/docker-registry/storagedriver"
+	"github.com/docker/docker-registry/storagedriver/testsuites"
+	. "gopkg.in/check.v1"
+)
+
+// Hook up gocheck into the "go test" runner.
+func Test(t *testing.T) { TestingT(t) }
+
+func init() {
+	inmemoryDriverConstructor := func() (storagedriver.StorageDriver, error) {
+		return NewDriver(), nil
+	}
+	testsuites.RegisterInProcessSuite(inmemoryDriverConstructor)
+	testsuites.RegisterIPCSuite("inmemory", nil)
+}