1 files changed, 175 insertions, 0 deletions
diff --git a/swarm/storage/mock/mem/mem.go b/swarm/storage/mock/mem/mem.go
new file mode 100644
index 000000000..8878309d0
--- /dev/null
+++ b/swarm/storage/mock/mem/mem.go
@@ -0,0 +1,175 @@
+// 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 mem implements a mock store that keeps all chunk data in memory.
+// While it can be used for testing on smaller scales, the main purpose of this
+// package is to provide the simplest reference implementation of a mock store.
+package mem
+
+import (
+	"archive/tar"
+	"bytes"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"sync"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/swarm/storage/mock"
+)
+
+// GlobalStore stores all chunk data and also keys and node addresses relations.
+// It implements mock.GlobalStore interface.
+type GlobalStore struct {
+	nodes map[string]map[common.Address]struct{}
+	data  map[string][]byte
+	mu    sync.Mutex
+}
+
+// NewGlobalStore creates a new instance of GlobalStore.
+func NewGlobalStore() *GlobalStore {
+	return &GlobalStore{
+		nodes: make(map[string]map[common.Address]struct{}),
+		data:  make(map[string][]byte),
+	}
+}
+
+// NewNodeStore returns a new instance of NodeStore that retrieves and stores
+// chunk data only for a node with address addr.
+func (s *GlobalStore) NewNodeStore(addr common.Address) *mock.NodeStore {
+	return mock.NewNodeStore(addr, s)
+}
+
+// Get returns chunk data if the chunk with key exists for node
+// on address addr.
+func (s *GlobalStore) Get(addr common.Address, key []byte) (data []byte, err error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if _, ok := s.nodes[string(key)][addr]; !ok {
+		return nil, mock.ErrNotFound
+	}
+
+	data, ok := s.data[string(key)]
+	if !ok {
+		return nil, mock.ErrNotFound
+	}
+	return data, nil
+}
+
+// Put saves the chunk data for node with address addr.
+func (s *GlobalStore) Put(addr common.Address, key []byte, data []byte) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if _, ok := s.nodes[string(key)]; !ok {
+		s.nodes[string(key)] = make(map[common.Address]struct{})
+	}
+	s.nodes[string(key)][addr] = struct{}{}
+	s.data[string(key)] = data
+	return nil
+}
+
+// HasKey returns whether a node with addr contains the key.
+func (s *GlobalStore) HasKey(addr common.Address, key []byte) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	_, ok := s.nodes[string(key)][addr]
+	return ok
+}
+
+// Import reads tar archive from a reader that contains exported chunk data.
+// It returns the number of chunks imported and an error.
+func (s *GlobalStore) Import(r io.Reader) (n int, err error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	tr := tar.NewReader(r)
+
+	for {
+		hdr, err := tr.Next()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return n, err
+		}
+
+		data, err := ioutil.ReadAll(tr)
+		if err != nil {
+			return n, err
+		}
+
+		var c mock.ExportedChunk
+		if err = json.Unmarshal(data, &c); err != nil {
+			return n, err
+		}
+
+		addrs := make(map[common.Address]struct{})
+		for _, a := range c.Addrs {
+			addrs[a] = struct{}{}
+		}
+
+		key := string(common.Hex2Bytes(hdr.Name))
+		s.nodes[key] = addrs
+		s.data[key] = c.Data
+		n++
+	}
+	return n, err
+}
+
+// Export writes to a writer a tar archive with all chunk data from
+// the store. It returns the number of chunks exported and an error.
+func (s *GlobalStore) Export(w io.Writer) (n int, err error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	tw := tar.NewWriter(w)
+	defer tw.Close()
+
+	buf := bytes.NewBuffer(make([]byte, 0, 1024))
+	encoder := json.NewEncoder(buf)
+	for key, addrs := range s.nodes {
+		al := make([]common.Address, 0, len(addrs))
+		for a := range addrs {
+			al = append(al, a)
+		}
+
+		buf.Reset()
+		if err = encoder.Encode(mock.ExportedChunk{
+			Addrs: al,
+			Data:  s.data[key],
+		}); err != nil {
+			return n, err
+		}
+
+		data := buf.Bytes()
+		hdr := &tar.Header{
+			Name: common.Bytes2Hex([]byte(key)),
+			Mode: 0644,
+			Size: int64(len(data)),
+		}
+		if err := tw.WriteHeader(hdr); err != nil {
+			return n, err
+		}
+		if _, err := tw.Write(data); err != nil {
+			return n, err
+		}
+		n++
+	}
+	return n, err
+}