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swarm/storage/mru: Renamed all comments to Feeds

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This commit is contained in:
Javier Peletier 2018-09-30 07:48:49 +02:00
parent f1e86ad9cf
commit b35622cf3c
14 changed files with 96 additions and 102 deletions
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4
swarm/storage/mru/cacheentry.go
View File

@ -30,7 +30,7 @@ const (
defaultRetrieveTimeout = 100 * time.Millisecond
)
// cacheEntry caches resource data and the metadata of its root chunk.
// cacheEntry caches the last known update of a specific Feed.
type cacheEntry struct {
Update
*bytes.Reader
@ -42,7 +42,7 @@ func (r *cacheEntry) Size(ctx context.Context, _ chan bool) (int64, error) {
return int64(len(r.Update.data)), nil
}
//returns the resource's topic
//returns the Feed's topic
func (r *cacheEntry) Topic() Topic {
return r.Feed.Topic
}

29
swarm/storage/mru/doc.go
View File

@ -1,43 +1,42 @@
/*
Package feeds defines Swarm Feeds.
A Mutable Resource is an entity which allows updates to a resource
Swarm Feeds allows a user to build an update feed about a particular topic
without resorting to ENS on each update.
The update scheme is built on swarm chunks with chunk keys following
a predictable, versionable pattern.
A Resource is tied to a unique identifier that is deterministically generated out of
A Feed is tied to a unique identifier that is deterministically generated out of
the chosen topic.
A Resource View is defined as a specific user's point of view about a particular resource.
Thus, a View is a Topic + the user's address (userAddr)
A Feed is defined as the series of updates of a specific user about a particular topic
Actual data updates are also made in the form of swarm chunks. The keys
of the updates are the hash of a concatenation of properties as follows:
updateAddr = H(View, Epoch ID)
updateAddr = H(Feed, Epoch ID)
where H is the SHA3 hash function
View is the combination of Topic and the user address
Feed is the combination of Topic and the user address
Epoch ID is a time slot. See the lookup package for more information.
A user looking up a resource would only need to know the View in order to
another user's updates
A user looking up a the latest update in a Feed only needs to know the Topic
and the other user's address.
The resource update data is:
resourcedata = View|Epoch|data
The Feed Update data is:
updatedata = Feed|Epoch|data
the full update data that goes in the chunk payload is:
The full update data that goes in the chunk payload is:
resourcedata|sign(resourcedata)
Structure Summary:
Request: Resource update with signature
ResourceUpdate: headers + data
Request: Feed Update with signature
Update: headers + data
Header: Protocol version and reserved for future use placeholders
ID: Information about how to locate a specific update
View: Author of the update and what is updating
Feed: Represents a user's series of publications about a specific Topic
Topic: Item that the updates are about
User: User who updates the resource
User: User who updates the Feed
Epoch: time slot where the update is stored
*/

2
swarm/storage/mru/error.go
View File

@ -52,7 +52,7 @@ func (e *Error) Code() int {
return e.code
}
// NewError creates a new Mutable Resource Error object with the specified code and custom error message
// NewError creates a new Swarm Feeds Error object with the specified code and custom error message
func NewError(code int, s string) error {
if code < 0 || code >= ErrCnt {
panic("no such error code!")

57
swarm/storage/mru/handler.go
View File

@ -57,7 +57,7 @@ func init() {
}
}
// NewHandler creates a new Mutable Resource API
// NewHandler creates a new Swarm Feeds API
func NewHandler(params *HandlerParams) *Handler {
fh := &Handler{
cache: make(map[uint64]*cacheEntry),
@ -74,13 +74,13 @@ func NewHandler(params *HandlerParams) *Handler {
return fh
}
// SetStore sets the store backend for the Mutable Resource API
// SetStore sets the store backend for the Swarm Feeds API
func (h *Handler) SetStore(store *storage.NetStore) {
h.chunkStore = store
}
// Validate is a chunk validation method
// If it looks like a resource update, the chunk address is checked against the userAddr of the update's signature
// If it looks like a feed update, the chunk address is checked against the userAddr of the update's signature
// It implements the storage.ChunkValidator interface
func (h *Handler) Validate(chunkAddr storage.Address, data []byte) bool {
dataLength := len(data)
@ -89,7 +89,7 @@ func (h *Handler) Validate(chunkAddr storage.Address, data []byte) bool {
}
// check if it is a properly formatted update chunk with
// valid signature and proof of ownership of the resource it is trying
// valid signature and proof of ownership of the feed it is trying
// to update
// First, deserialize the chunk
@ -99,9 +99,9 @@ func (h *Handler) Validate(chunkAddr storage.Address, data []byte) bool {
return false
}
// Verify signatures and that the signer actually owns the resource
// Verify signatures and that the signer actually owns the feed
// If it fails, it means either the signature is not valid, data is corrupted
// or someone is trying to update someone else's resource.
// or someone is trying to update someone else's feed.
if err := r.Verify(); err != nil {
log.Debug("Invalid feed update signature", "err", err)
return false
@ -110,14 +110,14 @@ func (h *Handler) Validate(chunkAddr storage.Address, data []byte) bool {
return true
}
// GetContent retrieves the data payload of the last synced update of the Mutable Resource
// GetContent retrieves the data payload of the last synced update of the Feed
func (h *Handler) GetContent(feed *Feed) (storage.Address, []byte, error) {
if feed == nil {
return nil, nil, NewError(ErrInvalidValue, "view is nil")
return nil, nil, NewError(ErrInvalidValue, "feed is nil")
}
feedUpdate := h.get(feed)
if feedUpdate == nil {
return nil, nil, NewError(ErrNotFound, "resource does not exist")
return nil, nil, NewError(ErrNotFound, "feed update not cached")
}
return feedUpdate.lastKey, feedUpdate.data, nil
}
@ -142,7 +142,7 @@ func (h *Handler) NewRequest(ctx context.Context, feed *Feed) (request *Request,
return nil, err
}
// not finding updates means that there is a network error
// or that the resource really does not have updates
// or that the feed really does not have updates
}
request.Feed = *feed
@ -157,13 +157,10 @@ func (h *Handler) NewRequest(ctx context.Context, feed *Feed) (request *Request,
return request, nil
}
// Lookup retrieves a specific or latest version of the resource
// Lookup works differently depending on the configuration of `ID`
// See the `ID` documentation and helper functions:
// `LookupLatest` and `LookupBefore`
// When looking for the latest update, it starts at the next period after the current time.
// upon failure tries the corresponding keys of each previous period until one is found
// (or startTime is reached, in which case there are no updates).
// Lookup retrieves a specific or latest feed update
// Lookup works differently depending on the configuration of `query`
// See the `query` documentation and helper functions:
// `NewQueryLatest` and `NewQuery`
func (h *Handler) Lookup(ctx context.Context, query *Query) (*cacheEntry, error) {
timeLimit := query.TimeLimit
@ -213,17 +210,17 @@ func (h *Handler) Lookup(ctx context.Context, query *Query) (*cacheEntry, error)
return nil, err
}
log.Info(fmt.Sprintf("Resource lookup finished in %d lookups", readCount))
log.Info(fmt.Sprintf("Feed lookup finished in %d lookups", readCount))
request, _ := requestPtr.(*Request)
if request == nil {
return nil, NewError(ErrNotFound, "no updates found")
return nil, NewError(ErrNotFound, "no feed updates found")
}
return h.updateCache(request)
}
// update mutable resource cache map with specified content
// update feed updates cache with specified content
func (h *Handler) updateCache(request *Request) (*cacheEntry, error) {
updateAddr := request.Addr()
@ -242,10 +239,10 @@ func (h *Handler) updateCache(request *Request) (*cacheEntry, error) {
return feedUpdate, nil
}
// Update adds an actual data update
// Uses the Mutable Resource metadata currently loaded in the resources map entry.
// It is the caller's responsibility to make sure that this data is not stale.
// Note that a Mutable Resource update cannot span chunks, and thus has a MAX NET LENGTH 4096, INCLUDING update header data and signature. An error will be returned if the total length of the chunk payload will exceed this limit.
// Update publishes a feed update
// Note that a Feed update cannot span chunks, and thus has a MAX NET LENGTH 4096, INCLUDING update header data and signature.
// This results in a max payload of `maxUpdateDataLength` (check update.go for more details)
// An error will be returned if the total length of the chunk payload will exceed this limit.
// Update can only check if the caller is trying to overwrite the very last known version, otherwise it just puts the update
// on the network.
func (h *Handler) Update(ctx context.Context, r *Request) (updateAddr storage.Address, err error) {
@ -280,18 +277,18 @@ func (h *Handler) Update(ctx context.Context, r *Request) (updateAddr storage.Ad
return r.idAddr, nil
}
// Retrieves the resource cache value for the given nameHash
func (h *Handler) get(view *Feed) *cacheEntry {
mapKey := view.mapKey()
// Retrieves the feed update cache value for the given nameHash
func (h *Handler) get(feed *Feed) *cacheEntry {
mapKey := feed.mapKey()
h.cacheLock.RLock()
defer h.cacheLock.RUnlock()
feedUpdate := h.cache[mapKey]
return feedUpdate
}
// Sets the resource cache value for the given View
func (h *Handler) set(view *Feed, feedUpdate *cacheEntry) {
mapKey := view.mapKey()
// Sets the feed update cache value for the given Feed
func (h *Handler) set(feed *Feed, feedUpdate *cacheEntry) {
mapKey := feed.mapKey()
h.cacheLock.Lock()
defer h.cacheLock.Unlock()
h.cache[mapKey] = feedUpdate

54
swarm/storage/mru/handler_test.go
View File

@ -89,12 +89,12 @@ func TestFeedsHandler(t *testing.T) {
}
defer teardownTest()
// create a new resource
// create a new Feed
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
topic, _ := NewTopic("Mess with Swarm Feeds code and see what ghost catches you", nil)
view := Feed{
feed := Feed{
Topic: topic,
User: signer.Address(),
}
@ -107,7 +107,7 @@ func TestFeedsHandler(t *testing.T) {
"clyde", // t=4285
}
request := NewFirstRequest(view.Topic) // this timestamps the update at t = 4200 (start time)
request := NewFirstRequest(feed.Topic) // this timestamps the update at t = 4200 (start time)
chunkAddress := make(map[string]storage.Address)
data := []byte(updates[0])
request.SetData(data)
@ -205,38 +205,38 @@ func TestFeedsHandler(t *testing.T) {
t.Fatal(err)
}
rsrc2, err := feedsHandler2.Lookup(ctx, NewQueryLatest(&request.Feed, lookup.NoClue))
update2, err := feedsHandler2.Lookup(ctx, NewQueryLatest(&request.Feed, lookup.NoClue))
if err != nil {
t.Fatal(err)
}
// last update should be "clyde"
if !bytes.Equal(rsrc2.data, []byte(updates[len(updates)-1])) {
t.Fatalf("resource data was %v, expected %v", string(rsrc2.data), updates[len(updates)-1])
if !bytes.Equal(update2.data, []byte(updates[len(updates)-1])) {
t.Fatalf("feed update data was %v, expected %v", string(update2.data), updates[len(updates)-1])
}
if rsrc2.Level != 22 {
t.Fatalf("resource epoch level was %d, expected 22", rsrc2.Level)
if update2.Level != 22 {
t.Fatalf("feed update epoch level was %d, expected 22", update2.Level)
}
if rsrc2.Base() != 0 {
t.Fatalf("resource epoch base time was %d, expected 0", rsrc2.Base())
if update2.Base() != 0 {
t.Fatalf("feed update epoch base time was %d, expected 0", update2.Base())
}
log.Debug("Latest lookup", "epoch base time", rsrc2.Base(), "epoch level", rsrc2.Level, "data", rsrc2.data)
log.Debug("Latest lookup", "epoch base time", update2.Base(), "epoch level", update2.Level, "data", update2.data)
// specific point in time
rsrc, err := feedsHandler2.Lookup(ctx, NewQuery(&request.Feed, 4284, lookup.NoClue))
update, err := feedsHandler2.Lookup(ctx, NewQuery(&request.Feed, 4284, lookup.NoClue))
if err != nil {
t.Fatal(err)
}
// check data
if !bytes.Equal(rsrc.data, []byte(updates[2])) {
t.Fatalf("resource data (historical) was %v, expected %v", string(rsrc2.data), updates[2])
if !bytes.Equal(update.data, []byte(updates[2])) {
t.Fatalf("feed update data (historical) was %v, expected %v", string(update2.data), updates[2])
}
log.Debug("Historical lookup", "epoch base time", rsrc2.Base(), "epoch level", rsrc2.Level, "data", rsrc2.data)
log.Debug("Historical lookup", "epoch base time", update2.Base(), "epoch level", update2.Level, "data", update2.data)
// beyond the first should yield an error
rsrc, err = feedsHandler2.Lookup(ctx, NewQuery(&request.Feed, startTime.Time-1, lookup.NoClue))
update, err = feedsHandler2.Lookup(ctx, NewQuery(&request.Feed, startTime.Time-1, lookup.NoClue))
if err == nil {
t.Fatalf("expected previous to fail, returned epoch %s data %v", rsrc.Epoch.String(), rsrc.data)
t.Fatalf("expected previous to fail, returned epoch %s data %v", update.Epoch.String(), update.data)
}
}
@ -266,11 +266,11 @@ func TestSparseUpdates(t *testing.T) {
defer teardownTest()
defer os.RemoveAll(datadir)
// create a new resource
// create a new Feed
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
topic, _ := NewTopic("Very slow updates", nil)
view := Feed{
feed := Feed{
Topic: topic,
User: signer.Address(),
}
@ -280,7 +280,7 @@ func TestSparseUpdates(t *testing.T) {
var epoch lookup.Epoch
var lastUpdateTime uint64
for T := uint64(0); T < today; T += 5 * Year {
request := NewFirstRequest(view.Topic)
request := NewFirstRequest(feed.Topic)
request.Epoch = lookup.GetNextEpoch(epoch, T)
request.data = generateData(T) // this generates some data that depends on T, so we can check later
request.Sign(signer)
@ -295,14 +295,14 @@ func TestSparseUpdates(t *testing.T) {
lastUpdateTime = T
}
query := NewQuery(&view, today, lookup.NoClue)
query := NewQuery(&feed, today, lookup.NoClue)
_, err = rh.Lookup(ctx, query)
if err != nil {
t.Fatal(err)
}
_, content, err := rh.GetContent(&view)
_, content, err := rh.GetContent(&feed)
if err != nil {
t.Fatal(err)
}
@ -321,7 +321,7 @@ func TestSparseUpdates(t *testing.T) {
t.Fatal(err)
}
_, content, err = rh.GetContent(&view)
_, content, err = rh.GetContent(&feed)
if err != nil {
t.Fatal(err)
}
@ -348,7 +348,7 @@ func TestValidator(t *testing.T) {
}
defer teardownTest()
// create new resource
// create new Feed
topic, _ := NewTopic(subtopicName, nil)
feed := Feed{
Topic: topic,
@ -382,7 +382,7 @@ func TestValidator(t *testing.T) {
}
// tests that the content address validator correctly checks the data
// tests that resource update chunks are passed through content address validator
// tests that Feed update chunks are passed through content address validator
// there is some redundancy in this test as it also tests content addressed chunks,
// which should be evaluated as invalid chunks by this validator
func TestValidatorInStore(t *testing.T) {
@ -409,7 +409,7 @@ func TestValidatorInStore(t *testing.T) {
t.Fatal(err)
}
// set up resource handler and add is as a validator to the localstore
// set up Swarm Feeds handler and add is as a validator to the localstore
fhParams := &HandlerParams{}
fh := NewHandler(fhParams)
store.Validators = append(store.Validators, fh)
@ -425,7 +425,7 @@ func TestValidatorInStore(t *testing.T) {
User: signer.Address(),
}
// create a resource update chunk with correct publickey
// create a feed update chunk with correct publickey
id := ID{
Epoch: lookup.Epoch{Time: 42,
Level: 1,

4
swarm/storage/mru/id.go
View File

@ -29,7 +29,7 @@ import (
// ID uniquely identifies an update on the network.
type ID struct {
Feed `json:"view"`
Feed `json:"feed"`
lookup.Epoch `json:"epoch"`
}
@ -38,7 +38,7 @@ type ID struct {
// Epoch EpochLength
const idLength = feedLength + lookup.EpochLength
// Addr calculates the resource update chunk address corresponding to this ID
// Addr calculates the feed update chunk address corresponding to this ID
func (u *ID) Addr() (updateAddr storage.Address) {
serializedData := make([]byte, idLength)
var cursor int

2
swarm/storage/mru/lookup/lookup.go
View File

@ -15,7 +15,7 @@
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
/*
Package lookup defines resource lookup algorithms and provides tools to place updates
Package lookup defines Feed lookup algorithms and provides tools to place updates
so they can be found
*/
package lookup

2
swarm/storage/mru/query.go
View File

@ -72,7 +72,7 @@ func NewQuery(feed *Feed, time uint64, hint lookup.Epoch) *Query {
}
}
// NewQueryLatest generates lookup parameters that look for the latest version of a resource
// NewQueryLatest generates lookup parameters that look for the latest update to a feed
func NewQueryLatest(feed *Feed, hint lookup.Epoch) *Query {
return NewQuery(feed, 0, hint)
}

12
swarm/storage/mru/request.go
View File

@ -27,7 +27,7 @@ import (
"github.com/ethereum/go-ethereum/swarm/storage/mru/lookup"
)
// Request represents an update and/or resource create message
// Request represents a request to sign or signed Feed Update message
type Request struct {
Update // actual content that will be put on the chunk, less signature
Signature *Signature
@ -62,7 +62,7 @@ func NewFirstRequest(topic Topic) *Request {
return request
}
// SetData stores the payload data the resource will be updated with
// SetData stores the payload data the feed update will be updated with
func (r *Request) SetData(data []byte) {
r.data = data
r.Signature = nil
@ -73,7 +73,7 @@ func (r *Request) IsUpdate() bool {
return r.Signature != nil
}
// Verify checks that signatures are valid and that the signer owns the resource to be updated
// Verify checks that signatures are valid
func (r *Request) Verify() (err error) {
if len(r.data) == 0 {
return NewError(ErrInvalidValue, "Update does not contain data")
@ -103,7 +103,7 @@ func (r *Request) Verify() (err error) {
return nil
}
// Sign executes the signature to validate the resource
// Sign executes the signature to validate the update message
func (r *Request) Sign(signer Signer) error {
r.Feed.User = signer.Address()
r.binaryData = nil //invalidate serialized data
@ -133,7 +133,7 @@ func (r *Request) Sign(signer Signer) error {
return nil
}
// GetDigest creates the resource update digest used in signatures
// GetDigest creates the feed update digest used in signatures
// the serialized payload is cached in .binaryData
func (r *Request) GetDigest() (result common.Hash, err error) {
hasher := hashPool.Get().(hash.Hash)
@ -174,7 +174,7 @@ func (r *Request) toChunk() (storage.Chunk, error) {
func (r *Request) fromChunk(updateAddr storage.Address, chunkdata []byte) error {
// for update chunk layout see Request definition
//deserialize the resource update portion
//deserialize the feed update portion
if err := r.Update.binaryGet(chunkdata[:len(chunkdata)-signatureLength]); err != nil {
return err
}

16
swarm/storage/mru/request_test.go
View File

@ -47,7 +47,7 @@ func areEqualJSON(s1, s2 string) (bool, error) {
}
// TestEncodingDecodingUpdateRequests ensures that requests are serialized properly
// while also checking cryptographically that only the owner of a resource can update it.
// while also checking cryptographically that only the owner of a Feed can update it.
func TestEncodingDecodingUpdateRequests(t *testing.T) {
charlie := newCharlieSigner() //Charlie
@ -75,12 +75,10 @@ func TestEncodingDecodingUpdateRequests(t *testing.T) {
t.Fatal("Expected Verify to fail since the message is not signed")
}
// We now assume that the resource was created and propagated. With rootAddr we can retrieve the resource metadata
// and recover the information above. To sign an update, we need the rootAddr and the metaHash to construct
// proof of ownership
// We now assume that the feed ypdate was created and propagated.
const expectedSignature = "0x32c2d2c7224e24e4d3ae6a10595fc6e945f1b3ecdf548a04d8247c240a50c9240076aa7730abad6c8a46dfea00cfb8f43b6211f02db5c4cc5ed8584cb0212a4d00"
const expectedJSON = `{"view":{"topic":"0x6120676f6f64207265736f75726365206e616d65000000000000000000000000","user":"0x876a8936a7cd0b79ef0735ad0896c1afe278781c"},"epoch":{"time":1000,"level":1},"protocolVersion":0,"data":"0x5468697320686f75722773207570646174653a20537761726d2039392e3020686173206265656e2072656c656173656421"}`
const expectedSignature = "0x7235b27a68372ddebcf78eba48543fa460864b0b0e99cb533fcd3664820e603312d29426dd00fb39628f5299480a69bf6e462838d78de49ce0704c754c9deb2601"
const expectedJSON = `{"feed":{"topic":"0x6120676f6f6420746f706963206e616d65000000000000000000000000000000","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!")
@ -138,7 +136,7 @@ func TestEncodingDecodingUpdateRequests(t *testing.T) {
t.Fatal("Expected DecodeUpdateRequest to fail when trying to interpret a corrupt message with an invalid signature")
}
// Now imagine Bob wants to create an update of his own about the same resource,
// Now imagine Bob wants to create an update of his own about the same Feed,
// signing a message with his private key
if err := request.Sign(bob); err != nil {
t.Fatalf("Error signing: %s", err)
@ -258,7 +256,7 @@ func TestReverse(t *testing.T) {
defer teardownTest()
topic, _ := NewTopic("Cervantes quotes", nil)
view := Feed{
feed := Feed{
Topic: topic,
User: signer.Address(),
}
@ -266,7 +264,7 @@ func TestReverse(t *testing.T) {
data := []byte("Donde una puerta se cierra, otra se abre")
request := new(Request)
request.Feed = view
request.Feed = feed
request.Epoch = epoch
request.data = data

4
swarm/storage/mru/resource_sign.go → swarm/storage/mru/sign.go
View File

@ -28,7 +28,7 @@ const signatureLength = 65
// Signature is an alias for a static byte array with the size of a signature
type Signature [signatureLength]byte
// Signer signs Mutable Resource update payloads
// Signer signs Feed update payloads
type Signer interface {
Sign(common.Hash) (Signature, error)
Address() common.Address
@ -65,7 +65,7 @@ func (s *GenericSigner) Address() common.Address {
return s.address
}
// getUserAddr extracts the address of the resource update signer
// getUserAddr extracts the address of the Feed update signer
func getUserAddr(digest common.Hash, signature Signature) (common.Address, error) {
pub, err := crypto.SigToPub(digest.Bytes(), signature[:])
if err != nil {

2
swarm/storage/mru/topic.go
View File

@ -74,7 +74,7 @@ func (t *Topic) FromHex(hex string) error {
return nil
}
// Name will try to extract the resource name out of the topic
// Name will try to extract the topic name out of the Topic
func (t *Topic) Name(relatedContent []byte) string {
nameBytes := *t
if relatedContent != nil {

4
swarm/storage/mru/update.go
View File

@ -37,7 +37,7 @@ type Header struct {
// Update encapsulates the information sent as part of a feed update
type Update struct {
Header Header //
ID // Resource update identifying information
ID // Feed Update identifying information
data []byte // actual data payload
}
@ -86,7 +86,7 @@ func (r *Update) binaryLength() int {
// binaryGet populates this instance from the information contained in the passed byte slice
func (r *Update) binaryGet(serializedData []byte) error {
if len(serializedData) < minimumUpdateDataLength {
return NewErrorf(ErrNothingToReturn, "chunk less than %d bytes cannot be a resource update chunk", minimumUpdateDataLength)
return NewErrorf(ErrNothingToReturn, "chunk less than %d bytes cannot be a feed update chunk", minimumUpdateDataLength)
}
dataLength := len(serializedData) - idLength - headerLength
// at this point we can be satisfied that we have the correct data length to read

6
swarm/storage/mru/view.go
View File

@ -25,13 +25,13 @@ import (
"github.com/ethereum/go-ethereum/swarm/storage"
)
// Feed represents a particular user's view of a resource
// Feed represents a particular user's stream of updates on a Topic
type Feed struct {
Topic Topic `json:"topic"`
User common.Address `json:"user"`
}
// View layout:
// Feed layout:
// TopicLength bytes
// userAddr common.AddressLength bytes
const feedLength = TopicLength + common.AddressLength
@ -51,7 +51,7 @@ func (u *Feed) mapKey() uint64 {
// binaryPut serializes this Feed instance into the provided slice
func (u *Feed) binaryPut(serializedData []byte) error {
if len(serializedData) != feedLength {
return NewErrorf(ErrInvalidValue, "Incorrect slice size to serialize View. Expected %d, got %d", feedLength, len(serializedData))
return NewErrorf(ErrInvalidValue, "Incorrect slice size to serialize Feed. Expected %d, got %d", feedLength, len(serializedData))
}
var cursor int
copy(serializedData[cursor:cursor+TopicLength], u.Topic[:TopicLength])