blob: 48a87bc60247c881022846faea5d357c3ab3558e [file] [log] [blame]
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package experiment provides functionality for experiments.
package experiment
import (
"context"
)
type contextKey struct{}
// Set is the set of experiments that are enabled for a request.
type Set struct {
set map[string]bool
}
// Active returns a list of all the active experiments in s.
func (s *Set) Active() []string {
if s == nil {
return nil
}
var es []string
for e := range s.set {
es = append(es, e)
}
return es
}
// FromContext returns the set of experiments enabled for the context.
func FromContext(ctx context.Context) *Set {
s, _ := ctx.Value(contextKey{}).(*Set)
return s
}
// NewSet creates a new experiment.Set with the data provided.
func NewSet(experimentNames ...string) *Set {
set := map[string]bool{}
for _, e := range experimentNames {
set[e] = true
}
return &Set{set: set}
}
// NewContext stores a set constructed from the provided experiment names in the context.
func NewContext(ctx context.Context, experimentNames ...string) context.Context {
return context.WithValue(ctx, contextKey{}, NewSet(experimentNames...))
}
// IsActive reports whether an experiment is active for this set.
func IsActive(ctx context.Context, experiment string) bool {
return FromContext(ctx).IsActive(experiment)
}
// IsActive reports whether an experiment is active for this set.
func (s *Set) IsActive(experiment string) bool {
if s == nil {
return false
}
return s.set[experiment]
}