lib/protoparser/graphite: properly parse Graphite line with whitespace after the timestamp

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1865

docs/CHANGELOG.md

@@ -27,6 +27,7 @@ sort: 15
 * BUGFIX: [vmrestore](https://docs.victoriametrics.com/vmrestore.html): properly resume downloading for partially downloaded big files. Previously such files were re-downloaded from the beginning after the interrupt. Now only the remaining parts of the file are downloaded. This allows saving network bandwidth. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/487).
 * BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): do not store the last query across vmui page reloads. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1694).
 * BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix `Cannot read properties of undefined` error at table view. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1797).
+* BUGFIX: properly parse Graphite plaintext lines with whitespace after the timestamp. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1865).
 
 
 ## [v1.69.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.69.0)

lib/protoparser/graphite/parser.go

@@ -114,15 +114,32 @@ func (r *Row) unmarshal(s string, tagsPool []Tag) ([]Tag, error) {
 	if err != nil {
 		return tagsPool, fmt.Errorf("cannot unmarshal value from %q: %w", tail[:n], err)
 	}
-	ts, err := fastfloat.Parse(tail[n+1:])
+	tail = stripTailSpace(tail[n+1:])
+	ts, err := fastfloat.Parse(tail)
 	if err != nil {
-		return tagsPool, fmt.Errorf("cannot unmarshal timestamp from %q: %w", tail[n+1:], err)
+		return tagsPool, fmt.Errorf("cannot unmarshal timestamp from %q: %w", tail, err)
 	}
 	r.Value = v
 	r.Timestamp = int64(ts)
 	return tagsPool, nil
 }
 
+func stripTailSpace(s string) string {
+	n := len(s)
+	for {
+		n--
+		if n < 0 {
+			return ""
+		}
+		ch := s[n]
+		// graphite text line protocol may use white space or tab as separator
+		// See https://github.com/grobian/carbon-c-relay/commit/f3ffe6cc2b52b07d14acbda649ad3fd6babdd528
+		if ch != ' ' && ch != '\t' {
+			return s[:n+1]
+		}
+	}
+}
+
 func unmarshalRows(dst []Row, s string, tagsPool []Tag) ([]Row, []Tag) {
 	for len(s) > 0 {
 		n := strings.IndexByte(s, '\n')

lib/protoparser/graphite/parser_test.go

@@ -288,6 +288,23 @@ func TestRowsUnmarshalSuccess(t *testing.T) {
 		}},
 	})
 
+	// Whitespace after the timestamp
+	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1865
+	f("foo.baz 125 1789 \na 1.34 567\t  ", &Rows{
+		Rows: []Row{
+			{
+				Metric:    "foo.baz",
+				Value:     125,
+				Timestamp: 1789,
+			},
+			{
+				Metric:    "a",
+				Value:     1.34,
+				Timestamp: 567,
+			},
+		},
+	})
+
 }
 
 func Test_streamContext_Read(t *testing.T) {