package storm import ( "github.com/asdine/storm/codec" "github.com/coreos/bbolt" ) // A Node in Storm represents the API to a BoltDB bucket. type Node interface { tx typeStore keyValueStore bucketScanner // From returns a new Storm node with a new bucket root below the current. // All DB operations on the new node will be executed relative to this bucket. From(addend ...string) Node // Bucket returns the bucket name as a slice from the root. // In the normal, simple case this will be empty. Bucket() []string // GetBucket returns the given bucket below the current node. GetBucket(tx *bolt.Tx, children ...string) *bolt.Bucket // CreateBucketIfNotExists creates the bucket below the current node if it doesn't // already exist. CreateBucketIfNotExists(tx *bolt.Tx, bucket string) (*bolt.Bucket, error) // WithTransaction returns a New Storm node that will use the given transaction. WithTransaction(tx *bolt.Tx) Node // Begin starts a new transaction. Begin(writable bool) (Node, error) // Codec used by this instance of Storm Codec() codec.MarshalUnmarshaler // WithCodec returns a New Storm Node that will use the given Codec. WithCodec(codec codec.MarshalUnmarshaler) Node // WithBatch returns a new Storm Node with the batch mode enabled. WithBatch(enabled bool) Node } // A Node in Storm represents the API to a BoltDB bucket. type node struct { s *DB // The root bucket. In the normal, simple case this will be empty. rootBucket []string // Transaction object. Nil if not in transaction tx *bolt.Tx // Codec of this node codec codec.MarshalUnmarshaler // Enable batch mode for read-write transaction, instead of update mode batchMode bool } // From returns a new Storm Node with a new bucket root below the current. // All DB operations on the new node will be executed relative to this bucket. func (n node) From(addend ...string) Node { n.rootBucket = append(n.rootBucket, addend...) return &n } // WithTransaction returns a new Storm Node that will use the given transaction. func (n node) WithTransaction(tx *bolt.Tx) Node { n.tx = tx return &n } // WithCodec returns a new Storm Node that will use the given Codec. func (n node) WithCodec(codec codec.MarshalUnmarshaler) Node { n.codec = codec return &n } // WithBatch returns a new Storm Node with the batch mode enabled. func (n node) WithBatch(enabled bool) Node { n.batchMode = enabled return &n } // Bucket returns the bucket name as a slice from the root. // In the normal, simple case this will be empty. func (n *node) Bucket() []string { return n.rootBucket } // Codec returns the EncodeDecoder used by this instance of Storm func (n *node) Codec() codec.MarshalUnmarshaler { return n.codec } // Detects if already in transaction or runs a read write transaction. // Uses batch mode if enabled. func (n *node) readWriteTx(fn func(tx *bolt.Tx) error) error { if n.tx != nil { return fn(n.tx) } if n.batchMode { return n.s.Bolt.Batch(func(tx *bolt.Tx) error { return fn(tx) }) } return n.s.Bolt.Update(func(tx *bolt.Tx) error { return fn(tx) }) } // Detects if already in transaction or runs a read transaction. func (n *node) readTx(fn func(tx *bolt.Tx) error) error { if n.tx != nil { return fn(n.tx) } return n.s.Bolt.View(func(tx *bolt.Tx) error { return fn(tx) }) }