planner

type InputSpec struct {
	ColumnTypes []byte
	Links       []LinkSpec
}

type LinkSpec struct {
	ProcessorID int
}

type LogicalPlan interface {
	GetTaskExtraParams() proto.ExtraParams
	ToTaskMeta() ([]byte, error)
	FromTaskMeta([]byte) error
	ToPhysicalPlan(PlanCtx) (*PhysicalPlan, error)
}

type OutputSpec struct {
	Links []LinkSpec
}

type PhysicalPlan struct {
	Processors []ProcessorSpec
}

type PipelineSpec interface {
	// ToSubtaskMeta converts the pipeline to a subtask meta
	ToSubtaskMeta(PlanCtx) ([]byte, error)
}

type PlanCtx struct {
	Ctx context.Context

	// integrate with current distribute framework
	SessionCtx sessionctx.Context
	TaskID     int64
	TaskKey    string
	TaskType   proto.TaskType
	ThreadCnt  int
	MaxNodeCnt int
	Keyspace   string

	// PreviousSubtaskMetas is subtask metas of previous steps.
	// We can remove this field if we find a better way to pass the result between steps.
	PreviousSubtaskMetas map[proto.Step][][]byte
	GlobalSort           bool
	NextTaskStep         proto.Step
	ExecuteNodesCnt      int

	Store kv.Storage
}

type Planner struct{}

type ProcessorSpec struct {
	ID       int
	Input    InputSpec
	Pipeline PipelineSpec
	Output   OutputSpec
	// We can remove this field if we find a better way to pass the result between steps.
	Step proto.Step
}