Add Column datatype

pkg/models/column.go

@@ -0,0 +1,163 @@
+package models
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"go.mongodb.org/mongo-driver/bson"
+	"go.mongodb.org/mongo-driver/bson/bsontype"
+)
+
+type Column struct {
+	Name           string
+	ValueType      bsontype.Type
+	StoredAsString bool
+	Field          *data.Field
+	Size           int
+}
+
+func (c *Column) AppendValue(rv bson.RawValue) error {
+	switch c.ValueType {
+	case bson.TypeBoolean:
+		if rv.Type != bson.TypeBoolean {
+			return fmt.Errorf("field \"%s\" should have boolean type", c.Name)
+		}
+
+		v := new(bool)
+		*v = rv.Boolean()
+		c.Field.Append(v)
+
+	case bson.TypeInt32:
+		if rv.Type != bson.TypeInt32 {
+			return fmt.Errorf("field \"%s\" should have int32 type", c.Name)
+		}
+
+		v := new(int32)
+		*v = rv.Int32()
+		c.Field.Append(v)
+
+	case bson.TypeInt64:
+		if rv.Type != bson.TypeInt64 {
+			return fmt.Errorf("field \"%s\" should have int64 type", c.Name)
+		}
+
+		v := new(int64)
+		*v = rv.Int64()
+		c.Field.Append(v)
+
+	case bson.TypeDouble:
+		if rv.Type != bson.TypeDouble {
+			return fmt.Errorf("field \"%s\" should have double type", c.Name)
+		}
+
+		v := new(float64)
+		*v = rv.Double()
+		c.Field.Append(v)
+
+	case bson.TypeString:
+		if rv.Type != bson.TypeString {
+			return fmt.Errorf("field \"%s\" should have string type", c.Name)
+		}
+
+		v := new(string)
+		*v = rv.StringValue()
+		c.Field.Append(v)
+
+	case bson.TypeDateTime:
+		if rv.Type != bson.TypeDateTime {
+			return fmt.Errorf("field \"%s\" should have datetime type", c.Name)
+		}
+
+		v := new(time.Time)
+		*v = rv.Time()
+		c.Field.Append(v)
+
+	case bson.TypeObjectID:
+		if rv.Type != bson.TypeObjectID {
+			return fmt.Errorf("field \"%s\" should have objectId type", c.Name)
+		}
+
+		v := new(string)
+		*v = rv.ObjectID().String()
+		c.Field.Append(v)
+
+	default:
+		v := new(string)
+		*v = rv.String()
+		c.Field.Append(v)
+	}
+
+	c.Size++
+	return nil
+}
+
+func NewColumn(rowIndex int, element bson.RawElement) *Column {
+	key := element.Key()
+	value := element.Value()
+	savedAsString := false
+	var field *data.Field
+
+	switch value.Type {
+	case bson.TypeBoolean:
+		field = data.NewField(key, nil, make([]*bool, rowIndex+1))
+		v := new(bool)
+		*v = value.Boolean()
+		field.Set(rowIndex, v)
+
+	case bson.TypeInt32:
+		field = data.NewField(key, nil, make([]*int32, rowIndex+1))
+		v := new(int32)
+		*v = value.Int32()
+		field.Set(rowIndex, v)
+
+	case bson.TypeInt64:
+		field = data.NewField(key, nil, make([]*int64, rowIndex+1))
+		v := new(int64)
+		*v = value.Int64()
+		field.Set(rowIndex, v)
+
+	case bson.TypeDouble:
+		field = data.NewField(key, nil, make([]*float64, rowIndex+1))
+		v := new(float64)
+		*v = value.Double()
+		field.Set(rowIndex, v)
+
+	case bson.TypeString:
+		field = data.NewField(key, nil, make([]*string, rowIndex+1))
+		v := new(string)
+		*v = value.StringValue()
+		field.Set(rowIndex, v)
+
+		savedAsString = true
+
+	case bson.TypeDateTime:
+		field = data.NewField(key, nil, make([]*time.Time, rowIndex+1))
+		v := new(time.Time)
+		*v = value.Time()
+		field.Set(rowIndex, v)
+
+	case bson.TypeObjectID:
+		field = data.NewField(key, nil, make([]*string, rowIndex+1))
+		v := new(string)
+		*v = value.ObjectID().String()
+		field.Set(rowIndex, v)
+
+		savedAsString = true
+	default:
+		field = data.NewField(key, nil, make([]*string, rowIndex+1))
+		v := new(string)
+		*v = value.String()
+		field.Set(rowIndex, v)
+
+		savedAsString = true
+	}
+
+	return &Column{
+		Name:           key,
+		ValueType:      value.Type,
+		StoredAsString: savedAsString,
+		Field:          field,
+		Size:           rowIndex + 1,
+	}
+}

pkg/plugin/query.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"github.com/haohanyang/mongodb-datasource/pkg/models"
 	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
 )
@@ -221,3 +222,48 @@ func initFrameField(element bson.RawElement, frame *data.Frame) columnDefinition
 
 	return d
 }
+
+func createTableFramesFromQuery_(ctx context.Context, cursor *mongo.Cursor) (*data.Frame, error) {
+
+	columns := make(map[string]*models.Column)
+	rowIndex := 0
+	for cursor.Next(ctx) {
+		var result bson.Raw
+		if err := cursor.Decode(&result); err != nil {
+			return nil, err
+		}
+
+		elements, err := result.Elements()
+		if err != nil {
+			return nil, err
+		}
+
+		for _, element := range elements {
+			name := element.Key()
+			if c, ok := columns[name]; ok {
+				err = c.AppendValue(element.Value())
+				if err != nil {
+					return nil, err
+				}
+			} else {
+				columns[name] = models.NewColumn(rowIndex, element)
+			}
+		}
+
+		for _, c := range columns {
+			// Pad other columns with null value
+			if c.Size != rowIndex+1 {
+				c.Field.Append(nil)
+			}
+		}
+
+		rowIndex++
+	}
+
+	frame := data.NewFrame("Table")
+	for _, c := range columns {
+		frame.Fields = append(frame.Fields, c.Field)
+	}
+
+	return frame, nil
+}