boltengine

Documentation

Overview

Package boltengine implements a BoltDB engine.

Example

package main

import (
	"io/ioutil"
	"log"
	"os"
	"path/filepath"

	"github.com/genjidb/genji"
)

func main() {
	dir, err := ioutil.TempDir("", "bolt")
	if err != nil {
		log.Fatal(err)
	}
	defer os.RemoveAll(dir)

	db, err := genji.Open(filepath.Join(dir, "my.db"))
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()
}

Index

• type Engine
  • func NewEngine(path string, mode os.FileMode, opts *bolt.Options) (*Engine, error)
  • func (e *Engine) Begin(ctx context.Context, opts engine.TxOptions) (engine.Transaction, error)
  • func (e *Engine) Close() error
  • func (e *Engine) Drop(ctx context.Context) error
  • func (e *Engine) NewTransientEngine(ctx context.Context) (engine.Engine, error)
• type Store
  • func (s *Store) Delete(k []byte) error
  • func (s *Store) Get(k []byte) ([]byte, error)
  • func (s *Store) Iterator(opts engine.IteratorOptions) engine.Iterator
  • func (s *Store) Put(k, v []byte) error
  • func (s *Store) Truncate() error
• type Transaction
  • func (t *Transaction) Commit() error
  • func (t *Transaction) CreateStore(name []byte) error
  • func (t *Transaction) DropStore(name []byte) error
  • func (t *Transaction) GetStore(name []byte) (engine.Store, error)
  • func (t *Transaction) Rollback() error

Examples

• Package
• NewEngine

Types

type Engine

type Engine struct {
	DB *bolt.DB
	// contains filtered or unexported fields
}

Engine represents a BoltDB engine. Each store is stored in a dedicated bucket.

func NewEngine

func NewEngine(path string, mode os.FileMode, opts *bolt.Options) (*Engine, error)

NewEngine creates a BoltDB engine. It takes the same argument as Bolt's Open function.

Example

package main

import (
	"context"
	"io/ioutil"
	"log"
	"os"
	"path/filepath"

	"github.com/genjidb/genji"
	"github.com/genjidb/genji/engine/boltengine"
)

func main() {
	dir, err := ioutil.TempDir("", "bolt")
	if err != nil {
		log.Fatal(err)
	}
	defer os.RemoveAll(dir)

	ng, err := boltengine.NewEngine(filepath.Join(dir, "genji.db"), 0o600, nil)
	if err != nil {
		log.Fatal(err)
	}

	db, err := genji.New(context.Background(), ng)
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()
}

func (*Engine) Begin

func (e *Engine) Begin(ctx context.Context, opts engine.TxOptions) (engine.Transaction, error)

Begin creates a transaction using Bolt's transaction API.

func (*Engine) Close

func (e *Engine) Close() error

Close the engine and underlying Bolt database.

func (*Engine) Drop

func (e *Engine) Drop(ctx context.Context) error

func (*Engine) NewTransientEngine

func (e *Engine) NewTransientEngine(ctx context.Context) (engine.Engine, error)

type Store

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

A Store is an implementation of the engine.Store interface using a bucket.

func (*Store) Delete

func (s *Store) Delete(k []byte) error

Delete a record by key. If not found, returns table.ErrDocumentNotFound. It hides the key without deleting the actual node from the tree, to tree rebalancing during iterations. It then adds it to a sub bucket containing the list of keys to delete when the transaction is committed.

func (*Store) Get

func (s *Store) Get(k []byte) ([]byte, error)

Get returns a value associated with the given key. If not found, returns engine.ErrKeyNotFound.

func (*Store) Iterator

func (s *Store) Iterator(opts engine.IteratorOptions) engine.Iterator

Iterator uses the Bolt bucket cursor.

func (*Store) Put

func (s *Store) Put(k, v []byte) error

Put stores a key value pair. If it already exists, it overrides it.

func (*Store) Truncate

func (s *Store) Truncate() error

Truncate deletes all the records of the store.

type Transaction

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

A Transaction uses Bolt's transactions.

func (*Transaction) Commit

func (t *Transaction) Commit() error

Commit the transaction.

func (*Transaction) CreateStore

func (t *Transaction) CreateStore(name []byte) error

CreateStore creates a bolt bucket and returns a store. If the store already exists, returns engine.ErrStoreAlreadyExists.

func (*Transaction) DropStore

func (t *Transaction) DropStore(name []byte) error

DropStore deletes the underlying bucket.

func (*Transaction) GetStore

func (t *Transaction) GetStore(name []byte) (engine.Store, error)

GetStore returns a store by name. The store uses a Bolt bucket.

func (*Transaction) Rollback

func (t *Transaction) Rollback() error

Rollback the transaction. Can be used safely after commit.