Documentation ¶
Index ¶
- Constants
- Variables
- type Batch
- type Batcher
- type Compacter
- type Database
- type Deleter
- type Iteratee
- type Iterator
- type KeyValueStore
- 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 Reader
- type Stater
- type Writer
Constants ¶
const IdealBatchSize = 100 * 1024
IdealBatchSize defines the size of the data batches should ideally add in one write.
Variables ¶
var OpenFileLimit = 64
Functions ¶
This section is empty.
Types ¶
type Batch ¶
type Batch interface { Writer Deleter // ValueSize retrieves the amount of data queued up for writing. ValueSize() int // Write flushes any accumulated data to disk. 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. A batch cannot be used concurrently.
type Batcher ¶ added in v1.0.0
type Batcher interface { // NewBatch creates a write-only database that buffers changes to its host db // until a final write is called. NewBatch() Batch }
Batcher wraps the NewBatch method of a backing data store.
type Compacter ¶ added in v1.0.0
type Compacter interface { // Compact flattens the underlying data store for the given key range. In essence, // deleted and overwritten versions are discarded, and the data is rearranged to // reduce the cost of operations needed to access them. // // A nil start is treated as a key before all keys in the data store; a nil limit // is treated as a key after all keys in the data store. If both is nil then it // will compact entire data store. Compact(start []byte, limit []byte) error }
Compacter wraps the Compact method of a backing data store.
type Database ¶
Database contains all the methods required by the high level database to not only access the key-value data store but also the chain freezer.
type Deleter ¶
type Deleter interface { // Delete removes the key from the key-value data store. Delete(key []byte) error }
Deleter wraps the Delete method of a backing data store.
type Iteratee ¶ added in v1.0.0
type Iteratee interface { // NewIterator creates a binary-alphabetical iterator over the entire keyspace // contained within the key-value database. NewIterator() Iterator // NewIteratorWithPrefix creates a binary-alphabetical iterator over a subset // of database content with a particular key prefix. NewIteratorWithPrefix(prefix []byte) Iterator }
Iteratee wraps the NewIterator methods of a backing data store.
type Iterator ¶ added in v1.0.0
type Iterator interface { // Next moves the iterator to the next key/value pair. It returns whether the // iterator is exhausted. Next() bool // Error returns any accumulated error. Exhausting all the key/value pairs // is not considered to be an error. Error() error // Key returns the key of the current key/value pair, or nil if done. The caller // should not modify the contents of the returned slice, and its contents may // change on the next call to Next. Key() []byte // Value returns the value of the current key/value pair, or nil if done. The // caller should not modify the contents of the returned slice, and its contents // may change on the next call to Next. Value() []byte // Release releases associated resources. Release should always succeed and can // be called multiple times without causing error. Release() }
Iterator iterates over a database's key/value pairs in ascending key order.
When it encounters an error any seek will return false and will yield no key/ value pairs. The error can be queried by calling the Error method. Calling Release is still necessary.
An iterator must be released after use, but it is not necessary to read an iterator until exhaustion. An iterator is not safe for concurrent use, but it is safe to use multiple iterators concurrently.
type KeyValueStore ¶ added in v1.0.0
KeyValueStore contains all the methods required to allow handling different key-value data stores backing the high level database.
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
}
* This is a test memory database. Do not use for any production it does not get persisted
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 Reader ¶ added in v1.0.0
type Reader interface { // Has retrieves if a key is present in the key-value data store. Has(key []byte) (bool, error) // Get retrieves the given key if it's present in the key-value data store. Get(key []byte) ([]byte, error) }
Reader wraps the Has and Get method of a backing data store.
Directories ¶
Path | Synopsis |
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Package leveldb implements the key-value database layer based on LevelDB.
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Package leveldb implements the key-value database layer based on LevelDB. |
Package memorydb implements the key-value database layer based on memory maps.
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Package memorydb implements the key-value database layer based on memory maps. |