Documentation
¶
Index ¶
- Constants
- Variables
- type Batch
- type Database
- type Deleter
- type FakeIpfsAdapter
- type IpfsAdapter
- type IpfsDatabase
- type LDBDatabase
- func (db *LDBDatabase) Close()
- func (db *LDBDatabase) Delete(key []byte) error
- func (db *LDBDatabase) Get(key []byte) ([]byte, error)
- func (db *LDBDatabase) Has(key []byte) (bool, error)
- func (db *LDBDatabase) LDB() *leveldb.DB
- func (db *LDBDatabase) Meter(prefix string)
- func (db *LDBDatabase) NewBatch() Batch
- func (db *LDBDatabase) NewIterator() iterator.Iterator
- func (db *LDBDatabase) NewIteratorWithPrefix(prefix []byte) iterator.Iterator
- func (db *LDBDatabase) Path() string
- func (db *LDBDatabase) Put(key []byte, value []byte) error
- type MemDatabase
- func (db *MemDatabase) Close()
- func (db *MemDatabase) Delete(key []byte) error
- func (db *MemDatabase) Get(key []byte) ([]byte, error)
- func (db *MemDatabase) Has(key []byte) (bool, error)
- func (db *MemDatabase) Keys() [][]byte
- func (db *MemDatabase) Len() int
- func (db *MemDatabase) NewBatch() Batch
- func (db *MemDatabase) Put(key []byte, value []byte) error
- type Putter
- type RemoteDatabase
Constants ¶
const IdealBatchSize = 100 * 1024
Code using batches should try to add this much data to the batch. The value was determined empirically.
Variables ¶
var OpenFileLimit = 64
Functions ¶
This section is empty.
Types ¶
type Batch ¶
type Batch interface {
Putter
Deleter
ValueSize() int // amount of data in the batch
Write() error
// Reset resets the batch for reuse
Reset()
}
Batch is a write-only database that commits changes to its host database when Write is called. Batch cannot be used concurrently.
func NewTableBatch ¶
NewTableBatch returns a Batch object which prefixes all keys with a given string.
type Database ¶
type Database interface {
Putter
Deleter
Get(key []byte) ([]byte, error)
Has(key []byte) (bool, error)
Close()
NewBatch() Batch
}
Database wraps all database operations. All methods are safe for concurrent use.
type Deleter ¶
Deleter wraps the database delete operation supported by both batches and regular databases.
type FakeIpfsAdapter ¶
type FakeIpfsAdapter struct {
// contains filtered or unexported fields
}
FakeIpfsAdapter is a fake IPFS for unit test.
func NewFakeIpfsAdapter ¶
func NewFakeIpfsAdapter() *FakeIpfsAdapter
NewFakeIpfsAdapter creates a new FakeIpfsAdapter instance.
func (*FakeIpfsAdapter) Cat ¶
func (adapter *FakeIpfsAdapter) Cat(path string) (io.ReadCloser, error)
func (*FakeIpfsAdapter) Unpin ¶
func (adapter *FakeIpfsAdapter) Unpin(path string) error
type IpfsAdapter ¶
type IpfsAdapter interface {
// Cat reads data from IPFS.
Cat(path string) (io.ReadCloser, error)
// Add adds and pin data to IPFS.
Add(r io.Reader) (string, error)
// Unpin unpins the data from IPFS, unpinned data may be removed by GC in future.
Unpin(path string) error
}
IpfsAdapter represents an adapter for IPFS access. It also makes a room for weaving fake IPFS in unit test.
type IpfsDatabase ¶
type IpfsDatabase struct {
// contains filtered or unexported fields
}
IpfsDatabase is a IPFS-based database.
func NewIpfsDB ¶
func NewIpfsDB(url string) *IpfsDatabase
NewIpfsDB creates a new IpfsDatabase instance with given url which is the IPFS node's API url.
func NewIpfsDbWithAdapter ¶
func NewIpfsDbWithAdapter(adapter IpfsAdapter) *IpfsDatabase
NewIpfsDbWithAdapter creates a new IpfsDatabase instance with given IPFS adapter.
func (*IpfsDatabase) Discard ¶
func (db *IpfsDatabase) Discard(key []byte) error
Discard data from IPFS network.
func (*IpfsDatabase) Get ¶
func (db *IpfsDatabase) Get(key []byte) ([]byte, error)
Get retrieves data from IPFS with given key.
func (*IpfsDatabase) Has ¶
func (db *IpfsDatabase) Has(key []byte) bool
Has checks if the data specified by given key can be retrieved.
type LDBDatabase ¶
type LDBDatabase struct {
// contains filtered or unexported fields
}
func NewLDBDatabase ¶
func NewLDBDatabase(file string, cache int, handles int) (*LDBDatabase, error)
NewLDBDatabase returns a LevelDB wrapped object.
func (*LDBDatabase) Close ¶
func (db *LDBDatabase) Close()
func (*LDBDatabase) Delete ¶
func (db *LDBDatabase) Delete(key []byte) error
Delete deletes the key from the queue and database
func (*LDBDatabase) Get ¶
func (db *LDBDatabase) Get(key []byte) ([]byte, error)
Get returns the given key if it's present.
func (*LDBDatabase) LDB ¶
func (db *LDBDatabase) LDB() *leveldb.DB
func (*LDBDatabase) Meter ¶
func (db *LDBDatabase) Meter(prefix string)
Meter configures the database metrics collectors and
func (*LDBDatabase) NewBatch ¶
func (db *LDBDatabase) NewBatch() Batch
func (*LDBDatabase) NewIterator ¶
func (db *LDBDatabase) NewIterator() iterator.Iterator
func (*LDBDatabase) NewIteratorWithPrefix ¶
func (db *LDBDatabase) NewIteratorWithPrefix(prefix []byte) iterator.Iterator
NewIteratorWithPrefix returns a iterator to iterate over subset of database content with a particular prefix.
func (*LDBDatabase) Path ¶
func (db *LDBDatabase) Path() string
Path returns the path to the database directory.
type MemDatabase ¶
type MemDatabase struct {
// contains filtered or unexported fields
}
func NewMemDatabase ¶
func NewMemDatabase() *MemDatabase
func NewMemDatabaseWithCap ¶
func NewMemDatabaseWithCap(size int) *MemDatabase
func (*MemDatabase) Close ¶
func (db *MemDatabase) Close()
func (*MemDatabase) Delete ¶
func (db *MemDatabase) Delete(key []byte) error
func (*MemDatabase) Keys ¶
func (db *MemDatabase) Keys() [][]byte
func (*MemDatabase) Len ¶
func (db *MemDatabase) Len() int
func (*MemDatabase) NewBatch ¶
func (db *MemDatabase) NewBatch() Batch
type Putter ¶
Putter wraps the database write operation supported by both batches and regular databases.
type RemoteDatabase ¶
type RemoteDatabase interface {
// Get gets data from database with given key.
Get(key []byte) ([]byte, error)
// Put puts data to database and returns an address(key/identifier).
Put(value []byte) ([]byte, error)
// Discard discards data from database with given key. As remote database system such as IPFS doesn't have explicit
// data deleting function as its own implementation mechanism, we adopt 'discard' instead of 'delete'.
Discard(key []byte) error
// Has checks if the given address/key points to an existent data.
Has(key []byte) bool
}
RemoteDatabase represents the database interface that be able to maintain a huge amount of data. Distributed p2p database such as ipfs is the classic implementation of the interface.
Source Files