Initial QSfera import

Server/vendor/contrib.go.opencensus.io/exporter/prometheus/sanitize.go

@@ -0,0 +1,38 @@
+// Copyright 2017, OpenCensus Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"github.com/prometheus/statsd_exporter/pkg/mapper"
+)
+
+const labelKeySizeLimit = 100
+
+// sanitize returns a string that is trunacated to 100 characters if it's too
+// long, and replaces non-alphanumeric characters to underscores.
+func sanitize(s string) string {
+	if len(s) == 0 {
+		return s
+	}
+	if len(s) > labelKeySizeLimit {
+		s = s[:labelKeySizeLimit]
+	}
+
+	s = mapper.EscapeMetricName(s)
+	if s[0] == '_' {
+		s = "key" + s
+	}
+	return s
+}