storage

package
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 Go to latest Published: May 18, 2022 License: GPL-3.0, GPL-3.0 Imports: 32 Imported by: 0

Documentation

Overview

Copyright 2016 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/>.

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/>.

Index

Constants

View Source 
const (
	ErrInit = iota
	ErrNotFound
	ErrIO
	ErrUnauthorized
	ErrInvalidValue
	ErrDataOverflow
	ErrNothingToReturn
	ErrCorruptData
	ErrInvalidSignature
	ErrNotSynced
	ErrPeriodDepth
	ErrCnt
)
View Source 
const (
	DataChunk = 0
	TreeChunk = 1
)
View Source 
const (
	BMTHash     = "BMT"
	SHA3Hash    = "SHA3" // http://golang.org/pkg/hash/#Hash
	DefaultHash = BMTHash
)
View Source 
const (
	ChunkProcessors = 8
)
View Source 
const KeyLength = 32
View Source 
const MaxPO = 16

Variables

View Source 
var (
	ErrChunkNotFound    = errors.New("chunk not found")
	ErrFetching         = errors.New("chunk still fetching")
	ErrChunkInvalid     = errors.New("invalid chunk")
	ErrChunkForward     = errors.New("cannot forward")
	ErrChunkUnavailable = errors.New("chunk unavailable")
	ErrChunkTimeout     = errors.New("timeout")
)
View Source 
var ZeroAddr = Address(common.Hash{}.Bytes())

Functions

func BytesToU64 

func BytesToU64(data []byte) uint64

func IsZeroAddr 

func IsZeroAddr(addr Address) bool

func NewHasherStore 

func NewHasherStore(chunkStore ChunkStore, hashFunc SwarmHasher, toEncrypt bool) *hasherStore

NewHasherStore creates a hasherStore object, which implements Putter and Getter interfaces. With the HasherStore you can put and get chunk data (which is just []byte) into a ChunkStore and the hasherStore will take core of encryption/decryption of data if necessary

func Proximity 

func Proximity(one, other []byte) (ret int)

func PutChunks 

func PutChunks(store *LocalStore, chunks ...*Chunk)

PutChunks adds chunks to localstore It waits for receive on the stored channel It logs but does not fail on delivery error

func U64ToBytes 

func U64ToBytes(val uint64) []byte

Types

type Address 

type Address []byte

func PyramidAppend 

func PyramidAppend(ctx context.Context, addr Address, reader io.Reader, putter Putter, getter Getter) (Address, func(context.Context) error, error)

func PyramidSplit 

func PyramidSplit(ctx context.Context, reader io.Reader, putter Putter, getter Getter) (Address, func(context.Context) error, error)

When splitting, data is given as a SectionReader, and the key is a hashSize long byte slice (Key), the root hash of the entire content will fill this once processing finishes. New chunks to store are store using the putter which the caller provides.

func TreeSplit 

func TreeSplit(ctx context.Context, data io.Reader, size int64, putter Putter) (k Address, wait func(context.Context) error, err error)

When splitting, data is given as a SectionReader, and the key is a hashSize long byte slice (Key), the root hash of the entire content will fill this once processing finishes. New chunks to store are store using the putter which the caller provides.

func (Address) Hex 

func (a Address) Hex() string

func (Address) Log 

func (a Address) Log() string

func (Address) MarshalJSON 

func (a Address) MarshalJSON() (out []byte, err error)

func (Address) Size 

func (a Address) Size() uint

func (Address) String 

func (a Address) String() string

func (*Address) UnmarshalJSON 

func (a *Address) UnmarshalJSON(value []byte) error

type AddressCollection 

type AddressCollection []Address

func NewAddressCollection 

func NewAddressCollection(l int) AddressCollection

func (AddressCollection) Len 

func (c AddressCollection) Len() int

func (AddressCollection) Less 

func (c AddressCollection) Less(i, j int) bool

func (AddressCollection) Swap 

func (c AddressCollection) Swap(i, j int)

type Chunk 

type Chunk struct {
	Addr  Address // always
	SData []byte  // nil if request, to be supplied by dpa
	Size  int64   // size of the data covered by the subtree encoded in this chunk
	//Source   Peer           // peer
	C    chan bool // to signal data delivery by the dpa
	ReqC chan bool // to signal the request done
	// contains filtered or unexported fields
}

Chunk also serves as a request object passed to ChunkStores in case it is a retrieval request, Data is nil and Size is 0 Note that Size is not the size of the data chunk, which is Data.Size() but the size of the subtree encoded in the chunk 0 if request, to be supplied by the dpa

func GenerateRandomChunk 

func GenerateRandomChunk(dataSize int64) *Chunk

func GenerateRandomChunks 

func GenerateRandomChunks(dataSize int64, count int) (chunks []*Chunk)

func NewChunk 

func NewChunk(addr Address, reqC chan bool) *Chunk

func (*Chunk) GetErrored 

func (c *Chunk) GetErrored() error

func (*Chunk) SetErrored 

func (c *Chunk) SetErrored(err error)

func (*Chunk) String 

func (c *Chunk) String() string

String() for pretty printing

func (*Chunk) WaitToStore 

func (c *Chunk) WaitToStore() error

type ChunkData 

type ChunkData []byte

func (ChunkData) Data 

func (c ChunkData) Data() []byte

func (ChunkData) Size 

func (c ChunkData) Size() int64

NOTE: this returns invalid data if chunk is encrypted

type ChunkStore 

type ChunkStore interface {
	Put(context.Context, *Chunk) // effectively there is no error even if there is an error
	Get(context.Context, Address) (*Chunk, error)
	Close()
}

ChunkStore interface is implemented by :

- MemStore: a memory cache - DbStore: local disk/db store - LocalStore: a combination (sequence of) memStore and dbStore - NetStore: cloud storage abstraction layer - FakeChunkStore: dummy store which doesn't store anything just implements the interface

type ChunkValidator 

type ChunkValidator interface {
	Validate(addr Address, data []byte) bool
}

type ChunkerParams 

type ChunkerParams struct {
	// contains filtered or unexported fields
}

type ContentAddressValidator 

type ContentAddressValidator struct {
	Hasher SwarmHasher
}

Provides method for validation of content address in chunks Holds the corresponding hasher to create the address

func NewContentAddressValidator 

func NewContentAddressValidator(hasher SwarmHasher) *ContentAddressValidator

Constructor

func (*ContentAddressValidator) Validate 

func (v *ContentAddressValidator) Validate(addr Address, data []byte) bool

Validate that the given key is a valid content address for the given data

type DBAPI 

type DBAPI struct {
	// contains filtered or unexported fields
}

wrapper of db-s to provide mockable custom local chunk store access to syncer

func NewDBAPI 

func NewDBAPI(loc *LocalStore) *DBAPI

func (*DBAPI) CurrentBucketStorageIndex 

func (d *DBAPI) CurrentBucketStorageIndex(po uint8) uint64

current storage counter of chunk db

func (*DBAPI) Get 

func (d *DBAPI) Get(ctx context.Context, addr Address) (*Chunk, error)

to obtain the chunks from address or request db entry only

func (*DBAPI) GetOrCreateRequest 

func (d *DBAPI) GetOrCreateRequest(ctx context.Context, addr Address) (*Chunk, bool)

to obtain the chunks from address or request db entry only

func (*DBAPI) Iterator 

func (d *DBAPI) Iterator(from uint64, to uint64, po uint8, f func(Address, uint64) bool) error

iteration storage counter and proximity order

func (*DBAPI) Put 

func (d *DBAPI) Put(ctx context.Context, chunk *Chunk)

to obtain the chunks from key or request db entry only

type FileStore 

type FileStore struct {
	ChunkStore
	// contains filtered or unexported fields
}

func NewFileStore 

func NewFileStore(store ChunkStore, params *FileStoreParams) *FileStore

func NewLocalFileStore 

func NewLocalFileStore(datadir string, basekey []byte) (*FileStore, error)

for testing locally

func (*FileStore) HashSize 

func (f *FileStore) HashSize() int

func (*FileStore) Retrieve 

func (f *FileStore) Retrieve(ctx context.Context, addr Address) (reader *LazyChunkReader, isEncrypted bool)

Public API. Main entry point for document retrieval directly. Used by the FS-aware API and httpaccess Chunk retrieval blocks on netStore requests with a timeout so reader will report error if retrieval of chunks within requested range time out. It returns a reader with the chunk data and whether the content was encrypted

func (*FileStore) Store 

func (f *FileStore) Store(ctx context.Context, data io.Reader, size int64, toEncrypt bool) (addr Address, wait func(context.Context) error, err error)

Public API. Main entry point for document storage directly. Used by the FS-aware API and httpaccess

type FileStoreParams 

type FileStoreParams struct {
	Hash string
}

func NewFileStoreParams 

func NewFileStoreParams() *FileStoreParams

type Getter 

type Getter interface {
	Get(context.Context, Reference) (ChunkData, error)
}

Getter is an interface to retrieve a chunk's data by its reference

type HashWithLength 

type HashWithLength struct {
	hash.Hash
}

func (*HashWithLength) ResetWithLength 

func (h *HashWithLength) ResetWithLength(length []byte)

type Hasher 

type Hasher func() hash.Hash

type JoinerParams 

type JoinerParams struct {
	ChunkerParams
	// contains filtered or unexported fields
}

type LDBDatabase 

type LDBDatabase struct {
	// contains filtered or unexported fields
}

func NewLDBDatabase 

func NewLDBDatabase(file string) (*LDBDatabase, error)

func (*LDBDatabase) Close 

func (db *LDBDatabase) Close()

func (*LDBDatabase) Delete 

func (db *LDBDatabase) Delete(key []byte) error

func (*LDBDatabase) Get 

func (db *LDBDatabase) Get(key []byte) ([]byte, error)

func (*LDBDatabase) LastKnownTD 

func (db *LDBDatabase) LastKnownTD() []byte

func (*LDBDatabase) NewIterator 

func (db *LDBDatabase) NewIterator() iterator.Iterator

func (*LDBDatabase) Put 

func (db *LDBDatabase) Put(key []byte, value []byte)

func (*LDBDatabase) Write 

func (db *LDBDatabase) Write(batch *leveldb.Batch) error

type LDBStore 

type LDBStore struct {
	// contains filtered or unexported fields
}

func NewLDBStore 

func NewLDBStore(params *LDBStoreParams) (s *LDBStore, err error)

TODO: Instead of passing the distance function, just pass the address from which distances are calculated to avoid the appearance of a pluggable distance metric and opportunities of bugs associated with providing a function different from the one that is actually used.

func NewMockDbStore 

func NewMockDbStore(params *LDBStoreParams, mockStore *mock.NodeStore) (s *LDBStore, err error)

NewMockDbStore creates a new instance of DbStore with mockStore set to a provided value. If mockStore argument is nil, this function behaves exactly as NewDbStore.

func (*LDBStore) Cleanup 

func (s *LDBStore) Cleanup()

func (*LDBStore) Close 

func (s *LDBStore) Close()

func (*LDBStore) CurrentBucketStorageIndex 

func (s *LDBStore) CurrentBucketStorageIndex(po uint8) uint64

func (*LDBStore) CurrentStorageIndex 

func (s *LDBStore) CurrentStorageIndex() uint64

func (*LDBStore) Export 

func (s *LDBStore) Export(out io.Writer) (int64, error)

Export writes all chunks from the store to a tar archive, returning the number of chunks written.

func (*LDBStore) Get 

func (s *LDBStore) Get(ctx context.Context, addr Address) (chunk *Chunk, err error)

func (*LDBStore) Import 

func (s *LDBStore) Import(in io.Reader) (int64, error)

of chunks read.

func (*LDBStore) Put 

func (s *LDBStore) Put(ctx context.Context, chunk *Chunk)

func (*LDBStore) ReIndex 

func (s *LDBStore) ReIndex()

func (*LDBStore) Size 

func (s *LDBStore) Size() uint64

func (*LDBStore) SyncIterator 

func (s *LDBStore) SyncIterator(since uint64, until uint64, po uint8, f func(Address, uint64) bool) error

SyncIterator(start, stop, po, f) calls f on each hash of a bin po from start to stop

type LDBStoreParams 

type LDBStoreParams struct {
	*StoreParams
	Path string
	Po   func(Address) uint8
}

func NewLDBStoreParams 

func NewLDBStoreParams(storeparams *StoreParams, path string) *LDBStoreParams

NewLDBStoreParams constructs LDBStoreParams with the specified values.

type LazyChunkReader 

type LazyChunkReader struct {
	Ctx context.Context
	// contains filtered or unexported fields
}

LazyChunkReader implements LazySectionReader

func TreeJoin 

func TreeJoin(ctx context.Context, addr Address, getter Getter, depth int) *LazyChunkReader

Join reconstructs original content based on a root key. When joining, the caller gets returned a Lazy SectionReader, which is seekable and implements on-demand fetching of chunks as and where it is read. New chunks to retrieve are coming from the getter, which the caller provides. If an error is encountered during joining, it appears as a reader error. The SectionReader. As a result, partial reads from a document are possible even if other parts are corrupt or lost. The chunks are not meant to be validated by the chunker when joining. This is because it is left to the DPA to decide which sources are trusted.

func (*LazyChunkReader) Context 

func (r *LazyChunkReader) Context() context.Context

func (*LazyChunkReader) Read 

func (r *LazyChunkReader) Read(b []byte) (read int, err error)

Read keeps a cursor so cannot be called simulateously, see ReadAt

func (*LazyChunkReader) ReadAt 

func (r *LazyChunkReader) ReadAt(b []byte, off int64) (read int, err error)

read at can be called numerous times concurrent reads are allowed Size() needs to be called synchronously on the LazyChunkReader first

func (*LazyChunkReader) Seek 

func (r *LazyChunkReader) Seek(offset int64, whence int) (int64, error)

func (*LazyChunkReader) Size 

func (r *LazyChunkReader) Size(ctx context.Context, quitC chan bool) (n int64, err error)

Size is meant to be called on the LazySectionReader

type LazySectionReader 

type LazySectionReader interface {
	Context() context.Context
	Size(context.Context, chan bool) (int64, error)
	io.Seeker
	io.Reader
	io.ReaderAt
}

Size, Seek, Read, ReadAt

type LazyTestSectionReader 

type LazyTestSectionReader struct {
	*io.SectionReader
}

func (*LazyTestSectionReader) Context 

func (r *LazyTestSectionReader) Context() context.Context

func (*LazyTestSectionReader) Size 

func (r *LazyTestSectionReader) Size(context.Context, chan bool) (int64, error)

type LocalStore 

type LocalStore struct {
	Validators []ChunkValidator

	DbStore *LDBStore
	// contains filtered or unexported fields
}

LocalStore is a combination of inmemory db over a disk persisted db implements a Get/Put with fallback (caching) logic using any 2 ChunkStores

func NewLocalStore 

func NewLocalStore(params *LocalStoreParams, mockStore *mock.NodeStore) (*LocalStore, error)

This constructor uses MemStore and DbStore as components

func NewTestLocalStoreForAddr 

func NewTestLocalStoreForAddr(params *LocalStoreParams) (*LocalStore, error)

func (*LocalStore) Close 

func (ls *LocalStore) Close()

Close the local store

func (*LocalStore) Get 

func (ls *LocalStore) Get(ctx context.Context, addr Address) (chunk *Chunk, err error)

Get(chunk *Chunk) looks up a chunk in the local stores This method is blocking until the chunk is retrieved so additional timeout may be needed to wrap this call if ChunkStores are remote and can have long latency

func (*LocalStore) GetOrCreateRequest 

func (ls *LocalStore) GetOrCreateRequest(ctx context.Context, addr Address) (chunk *Chunk, created bool)

retrieve logic common for local and network chunk retrieval requests

func (*LocalStore) Put 

func (ls *LocalStore) Put(ctx context.Context, chunk *Chunk)

Put is responsible for doing validation and storage of the chunk by using configured ChunkValidators, MemStore and LDBStore. If the chunk is not valid, its GetErrored function will return ErrChunkInvalid. This method will check if the chunk is already in the MemStore and it will return it if it is. If there is an error from the MemStore.Get, it will be returned by calling GetErrored on the chunk. This method is responsible for closing Chunk.ReqC channel when the chunk is stored in memstore. After the LDBStore.Put, it is ensured that the MemStore contains the chunk with the same data, but nil ReqC channel.

func (*LocalStore) RequestsCacheLen 

func (ls *LocalStore) RequestsCacheLen() int

RequestsCacheLen returns the current number of outgoing requests stored in the cache

type LocalStoreParams 

type LocalStoreParams struct {
	*StoreParams
	ChunkDbPath string
	Validators  []ChunkValidator `toml:"-"`
}

func NewDefaultLocalStoreParams 

func NewDefaultLocalStoreParams() *LocalStoreParams

func (*LocalStoreParams) Init 

func (p *LocalStoreParams) Init(path string)

this can only finally be set after all config options (file, cmd line, env vars) have been evaluated

type MapChunkStore 

type MapChunkStore struct {
	// contains filtered or unexported fields
}

MapChunkStore is a very simple ChunkStore implementation to store chunks in a map in memory.

func NewMapChunkStore 

func NewMapChunkStore() *MapChunkStore

func (*MapChunkStore) Close 

func (m *MapChunkStore) Close()

func (*MapChunkStore) Get 

func (m *MapChunkStore) Get(ctx context.Context, addr Address) (*Chunk, error)

func (*MapChunkStore) Put 

func (m *MapChunkStore) Put(ctx context.Context, chunk *Chunk)

type MemStore 

type MemStore struct {
	// contains filtered or unexported fields
}

func NewMemStore 

func NewMemStore(params *StoreParams, _ *LDBStore) (m *MemStore)

NewMemStore is instantiating a MemStore cache. We are keeping a record of all outgoing requests for chunks, that should later be delivered by peer nodes, in the `requests` LRU cache. We are also keeping all frequently requested chunks in the `cache` LRU cache.

`requests` LRU cache capacity should ideally never be reached, this is why for the time being it should be initialised with the same value as the LDBStore capacity.

func (*MemStore) Close 

func (s *MemStore) Close()

func (*MemStore) Get 

func (m *MemStore) Get(ctx context.Context, addr Address) (*Chunk, error)

func (*MemStore) Put 

func (m *MemStore) Put(ctx context.Context, c *Chunk)

type NetStore 

type NetStore struct {
	// contains filtered or unexported fields
}

NetStore implements the ChunkStore interface, this chunk access layer assumed 2 chunk stores local storage eg. LocalStore and network storage eg., NetStore access by calling network is blocking with a timeout

func NewNetStore 

func NewNetStore(localStore *LocalStore, retrieve func(ctx context.Context, chunk *Chunk) error) *NetStore

func (*NetStore) Close 

func (ns *NetStore) Close()

Close chunk store

func (*NetStore) Get 

func (ns *NetStore) Get(ctx context.Context, addr Address) (chunk *Chunk, err error)

Get is the entrypoint for local retrieve requests waits for response or times out

Get uses get method to retrieve request, but retries if the ErrChunkNotFound is returned by get, until the netStoreRetryTimeout is reached.

func (*NetStore) GetWithTimeout 

func (ns *NetStore) GetWithTimeout(ctx context.Context, addr Address, timeout time.Duration) (chunk *Chunk, err error)

GetWithTimeout makes a single retrieval attempt for a chunk with a explicit timeout parameter

func (*NetStore) Put 

func (ns *NetStore) Put(ctx context.Context, chunk *Chunk)

Put is the entrypoint for local store requests coming from storeLoop

type Peer 

type Peer interface{}

Peer is the recorded as Source on the chunk should probably not be here? but network should wrap chunk object

type Putter 

type Putter interface {
	Put(context.Context, ChunkData) (Reference, error)
	// RefSize returns the length of the Reference created by this Putter
	RefSize() int64
	// Close is to indicate that no more chunk data will be Put on this Putter
	Close()
	// Wait returns if all data has been store and the Close() was called.
	Wait(context.Context) error
}

Putter is responsible to store data and create a reference for it

type PyramidChunker 

type PyramidChunker struct {
	// contains filtered or unexported fields
}

func NewPyramidSplitter 

func NewPyramidSplitter(params *PyramidSplitterParams) (pc *PyramidChunker)

func (*PyramidChunker) Append 

func (pc *PyramidChunker) Append(ctx context.Context) (k Address, wait func(context.Context) error, err error)

func (*PyramidChunker) Join 

func (pc *PyramidChunker) Join(addr Address, getter Getter, depth int) LazySectionReader

func (*PyramidChunker) Split 

func (pc *PyramidChunker) Split(ctx context.Context) (k Address, wait func(context.Context) error, err error)

type PyramidSplitterParams 

type PyramidSplitterParams struct {
	SplitterParams
	// contains filtered or unexported fields
}

func NewPyramidSplitterParams 

func NewPyramidSplitterParams(addr Address, reader io.Reader, putter Putter, getter Getter, chunkSize int64) *PyramidSplitterParams

type Reference 

type Reference []byte

type SplitterParams 

type SplitterParams struct {
	ChunkerParams
	// contains filtered or unexported fields
}

type StoreParams 

type StoreParams struct {
	Hash                       SwarmHasher `toml:"-"`
	DbCapacity                 uint64
	CacheCapacity              uint
	ChunkRequestsCacheCapacity uint
	BaseKey                    []byte
}

func NewDefaultStoreParams 

func NewDefaultStoreParams() *StoreParams

func NewStoreParams 

func NewStoreParams(ldbCap uint64, cacheCap uint, requestsCap uint, hash SwarmHasher, basekey []byte) *StoreParams

type SwarmHash 

type SwarmHash interface {
	hash.Hash
	ResetWithLength([]byte)
}

type SwarmHasher 

type SwarmHasher func() SwarmHash

func MakeHashFunc 

func MakeHashFunc(hash string) SwarmHasher

type TreeChunker 

type TreeChunker struct {
	// contains filtered or unexported fields
}

func NewTreeJoiner 

func NewTreeJoiner(params *JoinerParams) *TreeChunker

func NewTreeSplitter 

func NewTreeSplitter(params *TreeSplitterParams) *TreeChunker

func (*TreeChunker) Append 

func (tc *TreeChunker) Append() (Address, func(), error)

func (*TreeChunker) Join 

func (tc *TreeChunker) Join(ctx context.Context) *LazyChunkReader

func (*TreeChunker) Split 

func (tc *TreeChunker) Split(ctx context.Context) (k Address, wait func(context.Context) error, err error)

type TreeEntry 

type TreeEntry struct {
	// contains filtered or unexported fields
}

Entry to create a tree node

func NewTreeEntry 

func NewTreeEntry(pyramid *PyramidChunker) *TreeEntry

type TreeSplitterParams 

type TreeSplitterParams struct {
	SplitterParams
	// contains filtered or unexported fields
}

Source Files

View all Source files

Directories

Path Synopsis
Package mock defines types that are used by different implementations of mock storages.
 Package mock defines types that are used by different implementations of mock storages.
db
Package db implements a mock store that keeps all chunk data in LevelDB database.
 Package db implements a mock store that keeps all chunk data in LevelDB database.
mem
Package mem implements a mock store that keeps all chunk data in memory.
 Package mem implements a mock store that keeps all chunk data in memory.
rpc
Package rpc implements an RPC client that connect to a centralized mock store.
 Package rpc implements an RPC client that connect to a centralized mock store.
test
Package test provides functions that are used for testing GlobalStorer implementations.
 Package test provides functions that are used for testing GlobalStorer implementations.
Package mru defines Mutable resource updates.
 Package mru defines Mutable resource updates.

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