skip empty string for start position

models/points.go

@@ -726,7 +726,7 @@ func skipWhitespace(buf []byte, i int) int {
 			return i
 		}
 
-		if buf[i] == ' ' || buf[i] == '\t' {
+		if buf[i] == ' ' || buf[i] == '\t' || buf[i] == 0 {
 			i += 1
 			continue
 		}

models/points_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"math"
+	"math/rand"
 	"reflect"
 	"strconv"
 	"strings"
@@ -1509,3 +1510,25 @@ func TestPrecisionString(t *testing.T) {
 		}
 	}
 }
+
+func TestParsePointsStringWithExtraBuffer(t *testing.T) {
+	b := make([]byte, 70*5000)
+	buf := bytes.NewBuffer(b)
+	key := "cpu,host=A,region=uswest"
+	buf.WriteString(fmt.Sprintf("%s value=%.3f 1\n", key, rand.Float64()))
+
+	points, err := models.ParsePointsString(buf.String())
+	if err != nil {
+		t.Fatalf("failed to write points: %s", err.Error())
+	}
+
+	pointKey := string(points[0].Key())
+
+	if len(key) != len(pointKey) {
+		t.Fatalf("expected length of both keys are same but got %d and %d", len(key), len(pointKey))
+	}
+
+	if key != pointKey {
+		t.Fatalf("expected both keys are same but got %s and %s", key, pointKey)
+	}
+}