Added plan descriptions for a few more primitives

Signed-off-by: Andres Taylor <andres@planetscale.com>

go/vt/vtgate/engine/fake_primitive_test.go

@@ -139,5 +139,5 @@ func wrapStreamExecute(prim Primitive, vcursor VCursor, bindVars map[string]*que
 }
 
 func (f *fakePrimitive) description() PlanDescription {
-	return PlanDescription{OperatorType: "fake - not implemented"}
+	return PlanDescription{OperatorType: "fake"}
 }

go/vt/vtgate/engine/memory_sort.go

@@ -23,6 +23,7 @@ import (
 	"math"
 	"reflect"
 	"sort"
+	"strings"
 
 	"vitess.io/vitess/go/sqltypes"
 	"vitess.io/vitess/go/vt/key"
@@ -201,20 +202,27 @@ func (ms *MemorySort) description() PlanDescription {
 }
 
 func orderByParamsToString(i interface{}) string {
-	ob := i.(OrderbyParams)
-	return ob.String()
+	return i.(OrderbyParams).String()
 }
 
+//GenericJoin will iterate over arrays, slices or maps, and executes the f function to get a
+//string representation of each element, and then uses strings.Join() join all the strings into a single one
 func GenericJoin(input interface{}, f func(interface{}) string) string {
 	sl := reflect.ValueOf(input)
-	str := ""
+	var keys []string
+	switch sl.Kind() {
+	case reflect.Slice:
 		for i := 0; i < sl.Len(); i++ {
-		if len(str) != 0 {
-			str += ","
+			keys = append(keys, f(sl.Index(i).Interface()))
 		}
-		str += f(sl.Index(i).Interface())
+	case reflect.Map:
+		for _, k := range sl.MapKeys() {
+			keys = append(keys, f(k.Interface()))
 		}
-	return str
+	default:
+		panic("GenericJoin doesn't know how to deal with " + sl.Kind().String())
+	}
+	return strings.Join(keys, ", ")
 }
 
 // sortHeap is sorted based on the orderBy params.

go/vt/vtgate/engine/ordered_aggregate.go

@@ -18,6 +18,9 @@ package engine
 
 import (
 	"fmt"
+	"strconv"
+
+	"vitess.io/vitess/go/vt/key"
 
 	"vitess.io/vitess/go/vt/proto/vtrpc"
 	"vitess.io/vitess/go/vt/vterrors"
@@ -67,6 +70,14 @@ func (ap AggregateParams) isDistinct() bool {
 	return ap.Opcode == AggregateCountDistinct || ap.Opcode == AggregateSumDistinct
 }
 
+func (ap AggregateParams) String() string {
+	if ap.Alias != "" {
+		return fmt.Sprintf("%s(%d) AS %s", ap.Opcode.String(), ap.Col, ap.Alias)
+	}
+
+	return fmt.Sprintf("%s(%d)", ap.Opcode.String(), ap.Col)
+}
+
 // AggregateOpcode is the aggregation Opcode.
 type AggregateOpcode int
 
@@ -394,9 +405,26 @@ func createEmptyValueFor(opcode AggregateOpcode) (sqltypes.Value, error) {
 	return sqltypes.NULL, vterrors.Errorf(vtrpc.Code_INVALID_ARGUMENT, "unknown aggregation %v", opcode)
 }
 
+func aggregateParamsToString(in interface{}) string {
+	return in.(AggregateParams).String()
+}
+
+func intToString(i interface{}) string {
+	return strconv.Itoa(i.(int))
+}
+
 func (oa *OrderedAggregate) description() PlanDescription {
+	orderByIndexes := GenericJoin(oa.Aggregates, aggregateParamsToString)
+	groupBy := GenericJoin(oa.Keys, intToString)
+	other := map[string]string{
+		"OrderBy":  orderByIndexes,
+		"GroupBy":  groupBy,
+		"Distinct": strconv.FormatBool(oa.HasDistinct),
+	}
 	return PlanDescription{
-		OperatorType: "OrderedAggregation not implemented",
-		Other:        nil,
+		OperatorType:      "Aggregate",
+		Variant:           "Ordered",
+		TargetDestination: key.DestinationVtGate{},
+		Other:             other,
 	}
 }

go/vt/vtgate/engine/plan_description.go

@@ -17,6 +17,8 @@ limitations under the License.
 package engine
 
 import (
+	"encoding/json"
+
 	"vitess.io/vitess/go/vt/key"
 	topodatapb "vitess.io/vitess/go/vt/proto/topodata"
 	"vitess.io/vitess/go/vt/vtgate/vindexes"
@@ -25,16 +27,42 @@ import (
 // PlanDescription is used to create a serializable representation of the Primitive tree
 type PlanDescription struct {
 	OperatorType string
-	Variant      string
+	Variant      string `json:",omitempty"`
 	// Keyspace specifies the keyspace to send the query to.
-	Keyspace *vindexes.Keyspace
+	Keyspace *vindexes.Keyspace `json:",omitempty"`
 	// TargetDestination specifies an explicit target destination to send the query to.
-	TargetDestination key.Destination
+	TargetDestination key.Destination `json:",omitempty"`
 	// TargetTabletType specifies an explicit target destination tablet type
 	// this is only used in conjunction with TargetDestination
-	TargetTabletType topodatapb.TabletType
-	Other            map[string]string
-	Inputs           []PlanDescription
+	TargetTabletType topodatapb.TabletType `json:",omitempty"`
+	Other            map[string]string     `json:",omitempty"`
+	Inputs           []PlanDescription     `json:",omitempty"`
+}
+
+// MarshalJSON serializes the PlanDescription into a JSON representation.
+func (pd *PlanDescription) MarshalJSON() ([]byte, error) {
+	var dest string
+	if pd.TargetDestination != nil {
+		dest = pd.TargetDestination.String()
+	}
+	out := struct {
+		OperatorType      string
+		Variant           string             `json:",omitempty"`
+		Keyspace          *vindexes.Keyspace `json:",omitempty"`
+		TargetDestination string             `json:",omitempty"`
+		TargetTabletType  string             `json:",omitempty"`
+		Other             map[string]string  `json:",omitempty"`
+		Inputs            []PlanDescription  `json:",omitempty"`
+	}{
+		OperatorType:      pd.OperatorType,
+		Variant:           pd.Variant,
+		Keyspace:          pd.Keyspace,
+		TargetDestination: dest,
+		TargetTabletType:  pd.TargetTabletType.String(),
+		Other:             pd.Other,
+		Inputs:            pd.Inputs,
+	}
+	return json.Marshal(out)
 }
 
 //PrimitiveToPlanDescription transforms a primitive tree into a corresponding PlanDescription tree

go/vt/vtgate/engine/pullout_subquery.go

@@ -19,6 +19,8 @@ package engine
 import (
 	"fmt"
 
+	"vitess.io/vitess/go/vt/key"
+
 	"vitess.io/vitess/go/sqltypes"
 	"vitess.io/vitess/go/vt/vterrors"
 
@@ -32,8 +34,11 @@ var _ Primitive = (*PulloutSubquery)(nil)
 // the results in a bind variable.
 type PulloutSubquery struct {
 	Opcode PulloutOpcode
+
+	// SubqueryResult and HasValues are used to send in the bindvar used in the query to the underlying primitive
 	SubqueryResult string
 	HasValues      string
+
 	Subquery   Primitive
 	Underlying Primitive
 }
@@ -154,7 +159,11 @@ func (ps *PulloutSubquery) execSubquery(vcursor VCursor, bindVars map[string]*qu
 }
 
 func (ps *PulloutSubquery) description() PlanDescription {
-	return PlanDescription{OperatorType: "pullout subquery not implemented"}
+	return PlanDescription{
+		OperatorType:      "Subquery",
+		Variant:           ps.Opcode.String(),
+		TargetDestination: key.DestinationVtGate{},
+	}
 }
 
 // PulloutOpcode is a number representing the opcode

go/vt/vtgate/engine/subquery.go

@@ -18,6 +18,7 @@ package engine
 
 import (
 	"vitess.io/vitess/go/sqltypes"
+	"vitess.io/vitess/go/vt/key"
 	querypb "vitess.io/vitess/go/vt/proto/query"
 )
 
@@ -104,5 +105,12 @@ func (sq *Subquery) buildFields(inner *sqltypes.Result) []*querypb.Field {
 }
 
 func (sq *Subquery) description() PlanDescription {
-	return PlanDescription{OperatorType: "subquery - not implemented"}
+	other := map[string]string{
+		"Columns": GenericJoin(sq.Cols, intToString),
+	}
+	return PlanDescription{
+		OperatorType:      "Subquery",
+		TargetDestination: key.DestinationVtGate{},
+		Other:             other,
+	}
 }

go/vt/vtgate/planbuilder/plan_test.go

@@ -301,13 +301,9 @@ func getPlanOrErrorOutput(err error, plan *engine.Plan) string {
 	}
 
 	descr := engine.PrimitiveToPlanDescription(plan.Instructions)
-	sss, _ := json.MarshalIndent(descr, "", "  ")
-	fmt.Println(string(sss))
 
-	bout, _ := json.MarshalIndent(testPlan{
-		Original:     plan.Original,
-		Instructions: plan.Instructions,
-	}, "", "  ")
+	bout, _ := json.MarshalIndent(descr, "  ", "  ")
+	fmt.Println(string(bout))
 	return string(bout)
 }