Add storj.StreamID (#2407)

internal/testrand/rand.go

@@ -93,6 +93,13 @@ func SerialNumber() storj.SerialNumber {
 	return serial
 }
 
+// StreamID creates a random stream ID
+func StreamID() storj.StreamID {
+	var streamID storj.StreamID
+	Read(streamID[:])
+	return streamID
+}
+
 // UUID creates a random uuid.
 func UUID() uuid.UUID {
 	var uuid uuid.UUID

pkg/pb/types.go

@@ -19,3 +19,6 @@ type PieceID = storj.PieceID
 
 // SerialNumber is an alias to storj.SerialNumber for use in generated protobuf code
 type SerialNumber = storj.SerialNumber
+
+// StreamID is an alias to storj.StreamID for use in generated protobuf code
+type StreamID = storj.StreamID

pkg/storj/streamid.go

@@ -0,0 +1,105 @@
+// Copyright (C) 2019 Storj Labs, Inc.
+// See LICENSE for copying information.
+
+package storj
+
+import (
+	"database/sql/driver"
+	"encoding/base32"
+
+	"github.com/zeebo/errs"
+)
+
+// ErrStreamID is used when something goes wrong with a stream ID
+var ErrStreamID = errs.Class("stream ID error")
+
+// streamIDEncoding is base32 without padding
+var streamIDEncoding = base32.StdEncoding.WithPadding(base32.NoPadding)
+
+// StreamID is the unique identifier for stream related to object
+type StreamID [16]byte
+
+// StreamIDFromString decodes an base32 encoded
+func StreamIDFromString(s string) (StreamID, error) {
+	idBytes, err := streamIDEncoding.DecodeString(s)
+	if err != nil {
+		return StreamID{}, ErrStreamID.Wrap(err)
+	}
+	return StreamIDFromBytes(idBytes)
+}
+
+// StreamIDFromBytes converts a byte slice into a stream ID
+func StreamIDFromBytes(b []byte) (StreamID, error) {
+	if len(b) != len(StreamID{}) {
+		return StreamID{}, ErrStreamID.New("not enough bytes to make a stream ID; have %d, need %d", len(b), len(NodeID{}))
+	}
+
+	var id StreamID
+	copy(id[:], b)
+	return id, nil
+}
+
+// IsZero returns whether stream ID is unassigned
+func (id StreamID) IsZero() bool {
+	return id == StreamID{}
+}
+
+// String representation of the stream ID
+func (id StreamID) String() string { return streamIDEncoding.EncodeToString(id.Bytes()) }
+
+// Bytes returns bytes of the stream ID
+func (id StreamID) Bytes() []byte { return id[:] }
+
+// Marshal serializes a stream ID
+func (id StreamID) Marshal() ([]byte, error) {
+	return id.Bytes(), nil
+}
+
+// MarshalTo serializes a stream ID into the passed byte slice
+func (id *StreamID) MarshalTo(data []byte) (n int, err error) {
+	n = copy(data, id.Bytes())
+	return n, nil
+}
+
+// Unmarshal deserializes a stream ID
+func (id *StreamID) Unmarshal(data []byte) error {
+	var err error
+	*id, err = StreamIDFromBytes(data)
+	return err
+}
+
+// Size returns the length of a stream ID (implements gogo's custom type interface)
+func (id *StreamID) Size() int {
+	return len(id)
+}
+
+// MarshalJSON serializes a stream ID to a json string as bytes
+func (id StreamID) MarshalJSON() ([]byte, error) {
+	return []byte(`"` + id.String() + `"`), nil
+}
+
+// UnmarshalJSON deserializes a json string (as bytes) to a stream ID
+func (id *StreamID) UnmarshalJSON(data []byte) error {
+	var err error
+	*id, err = StreamIDFromString(string(data))
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Value set a stream ID to a database field
+func (id StreamID) Value() (driver.Value, error) {
+	return id.Bytes(), nil
+}
+
+// Scan extracts a stream ID from a database field
+func (id *StreamID) Scan(src interface{}) (err error) {
+	b, ok := src.([]byte)
+	if !ok {
+		return ErrStreamID.New("Stream ID Scan expects []byte")
+	}
+	n, err := StreamIDFromBytes(b)
+	*id = n
+	return err
+}

pkg/storj/streamid_test.go

@@ -0,0 +1,33 @@
+// Copyright (C) 2019 Storj Labs, Inc.
+// See LICENSE for copying information.
+
+package storj_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"storj.io/storj/internal/testrand"
+	"storj.io/storj/pkg/storj"
+)
+
+func TestStreamID_Encode(t *testing.T) {
+	_, err := storj.StreamIDFromString("likn43kilfzd")
+	assert.Error(t, err)
+
+	_, err = storj.StreamIDFromBytes([]byte{1, 2, 3, 4, 5})
+	assert.Error(t, err)
+
+	for i := 0; i < 10; i++ {
+		streamID := testrand.StreamID()
+
+		fromString, err := storj.StreamIDFromString(streamID.String())
+		assert.NoError(t, err)
+		fromBytes, err := storj.StreamIDFromBytes(streamID.Bytes())
+		assert.NoError(t, err)
+
+		assert.Equal(t, streamID, fromString)
+		assert.Equal(t, streamID, fromBytes)
+	}
+}