swarm/storage/mru: Add version / header for future use

swarm/storage/mru/doc.go

@@ -33,12 +33,12 @@ Structure Summary:
 
 Request: Resource update with signature
 	ResourceUpdate: headers + data
-		UpdateHeader: (placeholder, to be deleted)
+		Header: Protocol version and reserved for future use placeholders
-			ID: Information about how to locate a specific update
+		ID: Information about how to locate a specific update
-				View: Author of the update and what is updating
+			View: Author of the update and what is updating
-					Topic: Item that the updates are about
+				Topic: Item that the updates are about
-					User: User who updates the resource
+				User: User who updates the resource
-				Epoch: time slot where the update is stored
+			Epoch: time slot where the update is stored
 
 */
 package mru

swarm/storage/mru/handler.go

@@ -123,13 +123,13 @@ func (h *Handler) GetContent(view *View) (storage.Address, []byte, error) {
 // just add the desired data and sign it.
 // The resulting structure can then be signed and passed to Handler.Update to be verified and sent
 func (h *Handler) NewRequest(ctx context.Context, view *View) (request *Request, err error) {
-
 	if view == nil {
 		return nil, NewError(ErrInvalidValue, "view cannot be nil")
 	}
 
 	now := TimestampProvider.Now().Time
 	request = new(Request)
+	request.Header.Version = ProtocolVersion
 
 	query := NewQueryLatest(view, lookup.NoClue)
 

swarm/storage/mru/request.go

@@ -38,8 +38,9 @@ type Request struct {
 // updateRequestJSON represents a JSON-serialized UpdateRequest
 type updateRequestJSON struct {
 	ID
-	Data      string `json:"data,omitempty"`
+	ProtocolVersion uint8  `json:"protocolVersion"`
-	Signature string `json:"signature,omitempty"`
+	Data            string `json:"data,omitempty"`
+	Signature       string `json:"signature,omitempty"`
 }
 
 var zeroAddr = common.Address{}
@@ -58,6 +59,7 @@ func NewFirstRequest(topic Topic) *Request {
 	now := TimestampProvider.Now().Time
 	request.Epoch = lookup.GetFirstEpoch(now)
 	request.View.Topic = topic
+	request.Header.Version = ProtocolVersion
 
 	return request
 }
@@ -230,6 +232,7 @@ func (r *Request) AppendValues(values Values) []byte {
 func (r *Request) fromJSON(j *updateRequestJSON) error {
 
 	r.ID = j.ID
+	r.Header.Version = j.ProtocolVersion
 
 	var err error
 	if j.Data != "" {
@@ -273,9 +276,10 @@ func (r *Request) MarshalJSON() (rawData []byte, err error) {
 	}
 
 	requestJSON := &updateRequestJSON{
-		ID:        r.ID,
+		ID:              r.ID,
-		Data:      dataString,
+		ProtocolVersion: r.Header.Version,
-		Signature: signatureString,
+		Data:            dataString,
+		Signature:       signatureString,
 	}
 
 	return json.Marshal(requestJSON)

swarm/storage/mru/request_test.go

@@ -79,8 +79,8 @@ func TestEncodingDecodingUpdateRequests(t *testing.T) {
 	// and recover the information above. To sign an update, we need the rootAddr and the metaHash to construct
 	// proof of ownership
 
-	const expectedSignature = "0x1cbdad7702b7d43ca983dc9f2ed87e73984288cdae6a8844e44688ee22c72080516fcd65a894b894b7b41ac780d5ce5d9fb527dc7126ea876501948d2bb6880d00"
+	const expectedSignature = "0x32c2d2c7224e24e4d3ae6a10595fc6e945f1b3ecdf548a04d8247c240a50c9240076aa7730abad6c8a46dfea00cfb8f43b6211f02db5c4cc5ed8584cb0212a4d00"
-	const expectedJSON = `{"view":{"topic":"0x6120676f6f64207265736f75726365206e616d65000000000000000000000000","user":"0x876a8936a7cd0b79ef0735ad0896c1afe278781c"},"epoch":{"level":1,"time":1000},"data":"0x5468697320686f75722773207570646174653a20537761726d2039392e3020686173206265656e2072656c656173656421"}`
+	const expectedJSON = `{"view":{"topic":"0x6120676f6f64207265736f75726365206e616d65000000000000000000000000","user":"0x876a8936a7cd0b79ef0735ad0896c1afe278781c"},"epoch":{"time":1000,"level":1},"protocolVersion":0,"data":"0x5468697320686f75722773207570646174653a20537761726d2039392e3020686173206265656e2072656c656173656421"}`
 
 	//Put together an unsigned update request that we will serialize to send it to the signer.
 	data := []byte("This hour's update: Swarm 99.0 has been released!")
@@ -225,7 +225,7 @@ func TestUpdateChunkSerializationErrorChecking(t *testing.T) {
 		t.Fatalf("error creating update chunk:%s", err)
 	}
 
-	compareByteSliceToExpectedHex(t, "chunk", chunk.Data(), "0x776f726c64206e657773207265706f72742c20657665727920686f7572000000876a8936a7cd0b79ef0735ad0896c1afe278781ce803000000000019416c206269656e206861636572206a616dc3a173206c652066616c7461207072656d696f376972cfb8bba6ad0c0f15e17f28bf03b6829649fddfc6b66d9de79a67f85c990982b513b09e8fd5365bde6920c8c73582ebf6f7fc85938b6d0dd285a3f18e2201")
+	compareByteSliceToExpectedHex(t, "chunk", chunk.Data(), "0x0000000000000000776f726c64206e657773207265706f72742c20657665727920686f7572000000876a8936a7cd0b79ef0735ad0896c1afe278781ce803000000000019416c206269656e206861636572206a616dc3a173206c652066616c7461207072656d696f5a0ffe0bc27f207cd5b00944c8b9cee93e08b89b5ada777f123ac535189333f174a6a4ca2f43a92c4a477a49d774813c36ce8288552c58e6205b0ac35d0507eb00")
 
 	var recovered Request
 	recovered.fromChunk(chunk.Address(), chunk.Data())

swarm/storage/mru/update.go

@@ -17,22 +17,32 @@
 package mru
 
 import (
+	"fmt"
+	"strconv"
+
 	"github.com/ethereum/go-ethereum/swarm/chunk"
 )
 
-// ResourceUpdate encapsulates the information sent as part of a resource update
+// ProtocolVersion defines the current version of the protocol that will be included in each update message
-type ResourceUpdate struct {
+const ProtocolVersion uint8 = 0
-	ID          // metainformation about this resource update
+
-	data []byte // actual data payload
+const headerLength = 8
+
+// Header defines a update message header including a protocol version byte
+type Header struct {
+	Version uint8                   // Protocol version
+	Padding [headerLength - 1]uint8 // reserved for future use
 }
 
-// Header: (see updateHeader)
+// ResourceUpdate encapsulates the information sent as part of a resource update
-// Data:
+type ResourceUpdate struct {
-// data (datalength bytes)
+	Header Header //
-//
+	ID            // Resource update identifying information
-// Minimum size is Header + 1 (minimum data length, enforced)
+	data   []byte // actual data payload
-const minimumUpdateDataLength = idLength + 1
+}
-const maxUpdateDataLength = chunk.DefaultSize - signatureLength - idLength
+
+const minimumUpdateDataLength = idLength + headerLength + 1
+const maxUpdateDataLength = chunk.DefaultSize - signatureLength - idLength - headerLength
 
 // binaryPut serializes the resource update information into the given slice
 func (r *ResourceUpdate) binaryPut(serializedData []byte) error {
@@ -50,7 +60,12 @@ func (r *ResourceUpdate) binaryPut(serializedData []byte) error {
 	}
 
 	var cursor int
-	// serialize header (see updateHeader)
+	// serialize Header
+	serializedData[cursor] = r.Header.Version
+	copy(serializedData[cursor+1:headerLength], r.Header.Padding[:headerLength-1])
+	cursor += headerLength
+
+	// serialize ID
 	if err := r.ID.binaryPut(serializedData[cursor : cursor+idLength]); err != nil {
 		return err
 	}
@@ -65,7 +80,7 @@ func (r *ResourceUpdate) binaryPut(serializedData []byte) error {
 
 // binaryLength returns the expected number of bytes this structure will take to encode
 func (r *ResourceUpdate) binaryLength() int {
-	return idLength + len(r.data)
+	return idLength + headerLength + len(r.data)
 }
 
 // binaryGet populates this instance from the information contained in the passed byte slice
@@ -73,9 +88,16 @@ func (r *ResourceUpdate) binaryGet(serializedData []byte) error {
 	if len(serializedData) < minimumUpdateDataLength {
 		return NewErrorf(ErrNothingToReturn, "chunk less than %d bytes cannot be a resource update chunk", minimumUpdateDataLength)
 	}
-	dataLength := len(serializedData) - idLength
+	dataLength := len(serializedData) - idLength - headerLength
-	var cursor int
 	// at this point we can be satisfied that we have the correct data length to read
+
+	var cursor int
+
+	// deserialize Header
+	r.Header.Version = serializedData[cursor]                                      // extract the protocol version
+	copy(r.Header.Padding[:headerLength-1], serializedData[cursor+1:headerLength]) // extract the padding
+	cursor += headerLength
+
 	if err := r.ID.binaryGet(serializedData[cursor : cursor+idLength]); err != nil {
 		return err
 	}
@@ -96,6 +118,8 @@ func (r *ResourceUpdate) binaryGet(serializedData []byte) error {
 // useful to parse query strings
 func (r *ResourceUpdate) FromValues(values Values, data []byte) error {
 	r.data = data
+	version, _ := strconv.ParseUint(values.Get("protocolVersion"), 10, 32)
+	r.Header.Version = uint8(version)
 	return r.ID.FromValues(values)
 }
 
@@ -103,5 +127,6 @@ func (r *ResourceUpdate) FromValues(values Values, data []byte) error {
 // useful to build query strings
 func (r *ResourceUpdate) AppendValues(values Values) []byte {
 	r.ID.AppendValues(values)
+	values.Set("protocolVersion", fmt.Sprintf("%d", r.Header.Version))
 	return r.data
 }

swarm/storage/mru/update_test.go

@@ -28,7 +28,7 @@ func getTestResourceUpdate() *ResourceUpdate {
 }
 
 func TestResourceUpdateSerializer(t *testing.T) {
-	testBinarySerializerRecovery(t, getTestResourceUpdate(), "0x776f726c64206e657773207265706f72742c20657665727920686f7572000000876a8936a7cd0b79ef0735ad0896c1afe278781ce803000000000019456c20717565206c6565206d7563686f207920616e6461206d7563686f2c207665206d7563686f20792073616265206d7563686f")
+	testBinarySerializerRecovery(t, getTestResourceUpdate(), "0x0000000000000000776f726c64206e657773207265706f72742c20657665727920686f7572000000876a8936a7cd0b79ef0735ad0896c1afe278781ce803000000000019456c20717565206c6565206d7563686f207920616e6461206d7563686f2c207665206d7563686f20792073616265206d7563686f")
 }
 
 func TestResourceUpdateLengthCheck(t *testing.T) {