etl

type Extract interface {

	// Extract raw records from source database to be transformed and loaded into target search index
	Extract(table config.FeatureTable, fields []string, where string, limit int, offset int) ([]t.RawRecord, error)

	// Close connection to source database
	Close()
}

type Load interface {

	// Init the target database by creating an empty search index
	Init(index string) error

	// Load records into search index
	Load(records []t.SearchIndexRecord, index string) (int64, error)

	// Close connection to target database
	Close()
}

type Transform interface {

	// Transform each raw record in one or more search records depending on the given configuration
	Transform(records []t.RawRecord, collection config.GeoSpatialCollection) ([]t.SearchIndexRecord, error)
}