Merge pull request #109 from sosedoff/bigint-to-string

Convert bigints that exceed js number limits to strings

pkg/client/client.go

@@ -193,6 +193,8 @@ func (client *Client) query(query string, args ...interface{}) (*Result, error)
 		}
 	}
 
+	result.PrepareBigints()
+
 	return &result, nil
 }
 

pkg/client/result.go

@@ -5,6 +5,8 @@ import (
 	"encoding/csv"
 	"encoding/json"
 	"fmt"
+	"reflect"
+	"strconv"
 )
 
 type Row []interface{}
@@ -14,6 +16,31 @@ type Result struct {
 	Rows    []Row    `json:"rows"`
 }
 
+// Due to big int number limitations in javascript, numbers should be encoded
+// as strings so they could be properly loaded on the frontend.
+func (res *Result) PrepareBigints() {
+	for i, row := range res.Rows {
+		for j, col := range row {
+			if col == nil {
+				continue
+			}
+
+			switch reflect.TypeOf(col).Kind() {
+			case reflect.Int64:
+				val := col.(int64)
+				if val < -9007199254740991 || val > 9007199254740991 {
+					res.Rows[i][j] = strconv.FormatInt(col.(int64), 10)
+				}
+			case reflect.Float64:
+				val := col.(float64)
+				if val < -999999999999999 || val > 999999999999999 {
+					res.Rows[i][j] = strconv.FormatFloat(val, 'e', -1, 64)
+				}
+			}
+		}
+	}
+}
+
 func (res *Result) Format() []map[string]interface{} {
 	var items []map[string]interface{}
 

pkg/client/result_test.go

@@ -7,6 +7,27 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func Test_PrepareBigints(t *testing.T) {
+	result := Result{
+		Columns: []string{"value"},
+		Rows: []Row{
+			Row{int(1234)},
+			Row{int64(9223372036854775807)},
+			Row{int64(-9223372036854775808)},
+			Row{float64(9223372036854775808.9223372036854775808)},
+			Row{float64(999999999999999.9)},
+		},
+	}
+
+	result.PrepareBigints()
+
+	assert.Equal(t, 1234, result.Rows[0][0])
+	assert.Equal(t, "9223372036854775807", result.Rows[1][0])
+	assert.Equal(t, "-9223372036854775808", result.Rows[2][0])
+	assert.Equal(t, "9.223372036854776e+18", result.Rows[3][0])
+	assert.Equal(t, "9.999999999999999e+14", result.Rows[4][0])
+}
+
 func Test_CSV(t *testing.T) {
 	result := Result{
 		Columns: []string{"id", "name", "email"},