erigon-pulse/ethdb/interface.go
2020-08-12 10:49:52 +07:00

126 lines
4.0 KiB
Go

// 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 ethdb
import (
"errors"
)
// DESCRIBED: For info on database buckets see docs/programmers_guide/db_walkthrough.MD
// ErrKeyNotFound is returned when key isn't found in the database.
var ErrKeyNotFound = errors.New("db: key not found")
// Putter wraps the database write operations.
type Putter interface {
// Put inserts or updates a single entry.
Put(bucket string, key, value []byte) error
}
// Getter wraps the database read operations.
type Getter interface {
// Get returns the value for a given key if it's present.
Get(bucket string, key []byte) ([]byte, error)
// Get returns prober chunk of index or error if index is not created.
// Key must contain 8byte inverted block number in the end.
GetIndexChunk(bucket string, key []byte, timestamp uint64) ([]byte, error)
// Has indicates whether a key exists in the database.
Has(bucket string, key []byte) (bool, error)
// Walk iterates over entries with keys greater or equal to startkey.
// Only the keys whose first fixedbits match those of startkey are iterated over.
// walker is called for each eligible entry.
// If walker returns false or an error, the walk stops.
Walk(bucket string, startkey []byte, fixedbits int, walker func(k, v []byte) (bool, error)) error
// MultiWalk is similar to multiple Walk calls folded into one.
MultiWalk(bucket string, startkeys [][]byte, fixedbits []int, walker func(int, []byte, []byte) error) error
}
type GetterPutter interface {
Getter
Putter
}
// Deleter wraps the database delete operations.
type Deleter interface {
// Delete removes a single entry.
Delete(bucket string, key []byte) error
}
// Database wraps all database operations. All methods are safe for concurrent use.
type Database interface {
Getter
Putter
Deleter
// MultiPut inserts or updates multiple entries.
// Entries are passed as an array:
// bucket0, key0, val0, bucket1, key1, val1, ...
MultiPut(tuples ...[]byte) (uint64, error)
Close()
NewBatch() DbWithPendingMutations // starts in-mem batch
Last(bucket string) ([]byte, []byte, error)
// IdealBatchSize defines the size of the data batches should ideally add in one write.
IdealBatchSize() int
Keys() ([][]byte, error)
// [TURBO-GETH] Freezer support (minimum amount that is actually used)
// FIXME: implement support if needed
Ancients() (uint64, error)
TruncateAncients(items uint64) error
ID() uint64
}
// MinDatabase is a minimalistic version of the Database interface.
type MinDatabase interface {
Get(bucket string, key []byte) ([]byte, error)
Put(bucket string, key, value []byte) error
Delete(bucket string, key []byte) error
}
// DbWithPendingMutations is an extended version of the Database,
// where all changes are first made in memory.
// Later they can either be committed to the database or rolled back.
type DbWithPendingMutations interface {
Database
Commit() (uint64, error)
Rollback()
BatchSize() int
}
type HasKV interface {
KV() KV
}
type HasNetInterface interface {
DB() Database
}
type NonTransactional interface {
BucketExists(bucket string) (bool, error) // makes them empty
ClearBuckets(buckets ...string) error // makes them empty
DropBuckets(buckets ...string) error // drops them, use of them after drop will panic
}
var errNotSupported = errors.New("not supported")