// Copyright 2023 Prometheus Team // 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 featurecontrol import ( "errors" "fmt" "strings" "github.com/go-kit/log" "github.com/go-kit/log/level" ) const ( FeatureReceiverNameInMetrics = "receiver-name-in-metrics" FeatureClassicMode = "classic-mode" FeatureUTF8StrictMode = "utf8-strict-mode" ) var AllowedFlags = []string{ FeatureReceiverNameInMetrics, FeatureClassicMode, FeatureUTF8StrictMode, } type Flagger interface { EnableReceiverNamesInMetrics() bool ClassicMode() bool UTF8StrictMode() bool } type Flags struct { logger log.Logger enableReceiverNamesInMetrics bool classicMode bool utf8StrictMode bool } func (f *Flags) EnableReceiverNamesInMetrics() bool { return f.enableReceiverNamesInMetrics } func (f *Flags) ClassicMode() bool { return f.classicMode } func (f *Flags) UTF8StrictMode() bool { return f.utf8StrictMode } type flagOption func(flags *Flags) func enableReceiverNameInMetrics() flagOption { return func(configs *Flags) { configs.enableReceiverNamesInMetrics = true } } func enableClassicMode() flagOption { return func(configs *Flags) { configs.classicMode = true } } func enableUTF8StrictMode() flagOption { return func(configs *Flags) { configs.utf8StrictMode = true } } func NewFlags(logger log.Logger, features string) (Flagger, error) { fc := &Flags{logger: logger} opts := []flagOption{} if len(features) == 0 { return NoopFlags{}, nil } for _, feature := range strings.Split(features, ",") { switch feature { case FeatureReceiverNameInMetrics: opts = append(opts, enableReceiverNameInMetrics()) level.Warn(logger).Log("msg", "Experimental receiver name in metrics enabled") case FeatureClassicMode: opts = append(opts, enableClassicMode()) level.Warn(logger).Log("msg", "Classic mode enabled") case FeatureUTF8StrictMode: opts = append(opts, enableUTF8StrictMode()) level.Warn(logger).Log("msg", "UTF-8 mode enabled") default: return nil, fmt.Errorf("Unknown option '%s' for --enable-feature", feature) } } for _, opt := range opts { opt(fc) } if fc.classicMode && fc.utf8StrictMode { return nil, errors.New("cannot have both classic and UTF-8 modes enabled") } return fc, nil } type NoopFlags struct{} func (n NoopFlags) EnableReceiverNamesInMetrics() bool { return false } func (n NoopFlags) ClassicMode() bool { return false } func (n NoopFlags) UTF8StrictMode() bool { return false }