graph

type BatchWriter interface {
	quad.WriteCloser
	Flush() error
}

type Delta struct {
	Quad   quad.Quad
	Action Procedure
}

type DeltaError struct {
	Delta Delta
	Err   error
}

type Handle struct {
	QuadStore
	QuadWriter
}

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

type IgnoreOpts struct {
	IgnoreDup, IgnoreMissing bool
}

type InitStoreFunc func(string, Options) error

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

type NewQuadWriterFunc func(QuadStore, Options) (QuadWriter, error)

type NewStoreFunc func(string, Options) (QuadStore, error)

type Options map[string]interface{}

type Procedure int8

type QuadIndexer interface {
	// Given an opaque token, returns the quad for that token from the store.
	Quad(Ref) quad.Quad

	// Given a direction and a token, creates an iterator of links which have
	// that node token in that directional field.
	QuadIterator(quad.Direction, Ref) iterator.Shape

	// QuadIteratorSize returns an estimated size of an iterator.
	QuadIteratorSize(ctx context.Context, d quad.Direction, v Ref) (refs.Size, error)

	// Convenience function for speed. Given a quad token and a direction
	// return the node token for that direction. Sometimes, a QuadStore
	// can do this without going all the way to the backing store, and
	// gives the QuadStore the opportunity to make this optimization.
	//
	// Iterators will call this. At worst, a valid implementation is
	//
	//  qs.ValueOf(qs.Quad(id).Get(dir))
	//
	QuadDirection(id Ref, d quad.Direction) Ref

	// Stats returns the number of nodes and quads currently stored.
	// Exact flag controls the correctness of the value. It can be an estimation, or a precise calculation.
	// The quadstore may have a fast way of retrieving the precise stats, in this case it may ignore 'exact'
	// flag and always return correct stats (with an appropriate flags set in the output).
	Stats(ctx context.Context, exact bool) (Stats, error)
}

type QuadStore interface {
	refs.Namer
	QuadIndexer

	// The only way in is through building a transaction, which
	// is done by a replication strategy.
	ApplyDeltas(in []Delta, opts IgnoreOpts) error

	// NewQuadWriter starts a batch quad import process.
	// The order of changes is not guaranteed, neither is the order and result of concurrent ApplyDeltas.
	NewQuadWriter() (quad.WriteCloser, error)

	// Returns an iterator enumerating all nodes in the graph.
	NodesAllIterator() iterator.Shape

	// Returns an iterator enumerating all links in the graph.
	QuadsAllIterator() iterator.Shape

	// Close the quad store and clean up. (Flush to disk, cleanly
	// sever connections, etc)
	Close() error
}

type QuadStoreRegistration struct {
	NewFunc      NewStoreFunc
	UpgradeFunc  UpgradeStoreFunc
	InitFunc     InitStoreFunc
	IsPersistent bool
}

type QuadWriter interface {
	// AddQuad adds a quad to the store.
	AddQuad(quad.Quad) error

	// TODO(barakmich): Deprecate in favor of transaction.
	// AddQuadSet adds a set of quads to the store, atomically if possible.
	AddQuadSet([]quad.Quad) error

	// RemoveQuad removes a quad matching the given one  from the database,
	// if it exists. Does nothing otherwise.
	RemoveQuad(quad.Quad) error

	// ApplyTransaction applies a set of quad changes.
	ApplyTransaction(*Transaction) error

	// RemoveNode removes all quads which have the given node as subject, predicate, object, or label.
	//
	// It returns ErrNodeNotExists if node is missing.
	RemoveNode(quad.Value) error

	// Close cleans up replication and closes the writing aspect of the database.
	Close() error
}

type Ref = refs.Ref

type Stats struct {
	Nodes refs.Size // number of nodes
	Quads refs.Size // number of quads
}

type Transaction struct {
	// Deltas stores the deltas in the right order
	Deltas []Delta
	// contains filtered or unexported fields
}

type UpgradeStoreFunc func(string, Options) error