diff options
author | Viktor TrĂ³n <viktor.tron@gmail.com> | 2018-10-03 20:59:41 +0800 |
---|---|---|
committer | GitHub <noreply@github.com> | 2018-10-03 20:59:41 +0800 |
commit | e5677114dc7461fe39ebe353a4657aa4cb03fde4 (patch) | |
tree | 8605f9a8b726b158fd01b4befced1e3ba92ca1f9 /swarm/storage/feed/id.go | |
parent | 303b99663e963a520aaa44eca68e042d9fe230af (diff) | |
parent | de01178c18766b9f744acc94fe2b96804f998e40 (diff) | |
download | dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar.gz dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar.bz2 dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar.lz dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar.xz dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.tar.zst dexon-e5677114dc7461fe39ebe353a4657aa4cb03fde4.zip |
Merge pull request #17796 from epiclabs-io/mru-feeds
swarm/storage/feeds: Renamed MRU to Swarm Feeds
Diffstat (limited to 'swarm/storage/feed/id.go')
-rw-r--r-- | swarm/storage/feed/id.go | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/swarm/storage/feed/id.go b/swarm/storage/feed/id.go new file mode 100644 index 000000000..7e17743c1 --- /dev/null +++ b/swarm/storage/feed/id.go @@ -0,0 +1,123 @@ +// Copyright 2018 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +package feed + +import ( + "fmt" + "hash" + "strconv" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/swarm/storage/feed/lookup" + + "github.com/ethereum/go-ethereum/swarm/storage" +) + +// ID uniquely identifies an update on the network. +type ID struct { + Feed `json:"feed"` + lookup.Epoch `json:"epoch"` +} + +// ID layout: +// Feed feedLength bytes +// Epoch EpochLength +const idLength = feedLength + lookup.EpochLength + +// 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 + u.Feed.binaryPut(serializedData[cursor : cursor+feedLength]) + cursor += feedLength + + eid := u.Epoch.ID() + copy(serializedData[cursor:cursor+lookup.EpochLength], eid[:]) + + hasher := hashPool.Get().(hash.Hash) + defer hashPool.Put(hasher) + hasher.Reset() + hasher.Write(serializedData) + return hasher.Sum(nil) +} + +// binaryPut serializes this instance into the provided slice +func (u *ID) binaryPut(serializedData []byte) error { + if len(serializedData) != idLength { + return NewErrorf(ErrInvalidValue, "Incorrect slice size to serialize ID. Expected %d, got %d", idLength, len(serializedData)) + } + var cursor int + if err := u.Feed.binaryPut(serializedData[cursor : cursor+feedLength]); err != nil { + return err + } + cursor += feedLength + + epochBytes, err := u.Epoch.MarshalBinary() + if err != nil { + return err + } + copy(serializedData[cursor:cursor+lookup.EpochLength], epochBytes[:]) + cursor += lookup.EpochLength + + return nil +} + +// binaryLength returns the expected size of this structure when serialized +func (u *ID) binaryLength() int { + return idLength +} + +// binaryGet restores the current instance from the information contained in the passed slice +func (u *ID) binaryGet(serializedData []byte) error { + if len(serializedData) != idLength { + return NewErrorf(ErrInvalidValue, "Incorrect slice size to read ID. Expected %d, got %d", idLength, len(serializedData)) + } + + var cursor int + if err := u.Feed.binaryGet(serializedData[cursor : cursor+feedLength]); err != nil { + return err + } + cursor += feedLength + + if err := u.Epoch.UnmarshalBinary(serializedData[cursor : cursor+lookup.EpochLength]); err != nil { + return err + } + cursor += lookup.EpochLength + + return nil +} + +// FromValues deserializes this instance from a string key-value store +// useful to parse query strings +func (u *ID) FromValues(values Values) error { + level, _ := strconv.ParseUint(values.Get("level"), 10, 32) + u.Epoch.Level = uint8(level) + u.Epoch.Time, _ = strconv.ParseUint(values.Get("time"), 10, 64) + + if u.Feed.User == (common.Address{}) { + return u.Feed.FromValues(values) + } + return nil +} + +// AppendValues serializes this structure into the provided string key-value store +// useful to build query strings +func (u *ID) AppendValues(values Values) { + values.Set("level", fmt.Sprintf("%d", u.Epoch.Level)) + values.Set("time", fmt.Sprintf("%d", u.Epoch.Time)) + u.Feed.AppendValues(values) +} |