Google create_experiment_config / main.go

// Copyright 2020 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.
// Command create_experiment_config creates an experiment.yaml file, which will
// set a rollout of 100 for all experiments.
package main
import (
    "fmt"
    "log"
    "os"
    "sort"
    "strings"
    "github.com/ghodss/yaml"
    "golang.org/x/pkgsite/internal"
)
type Experiment struct {
    Name    string `yaml:"name"`
    Rollout int    `yaml:"rollout"`
}
func main() {
    data, err := experimentsYAML()
    if err != nil {
        log.Fatal(err)
    }
    if err := writeConfigFile(data); err != nil {
        log.Fatal(err)
    }
}
func experimentsYAML() ([]byte, error) {
    var exps []*Experiment
    for e := range internal.Experiments {
        exps = append(exps, &Experiment{
            Name:    e,
            Rollout: 100,
        })
    }
    sort.Slice(exps, func(i, j int) bool { return exps[i].Name < exps[j].Name })
    data := map[string][]*Experiment{"experiments": exps}
    return yaml.Marshal(&data)
}
func writeConfigFile(data []byte) error {
    path, err := os.Getwd()
    if err != nil {
        return err
    }
    p := strings.TrimSuffix(path, "/devtools/cmd/run_beta") + "/experiment.yaml"
    f, err := os.Create(p)
    if err != nil {
        return err
    }
    if _, err = f.Write(data); err != nil {
        // Ignore f.Close() error, since f.Write returned an error.
        _ = f.Close()
        return err
    }
    if err := f.Close(); err != nil {
        return err
    }
    fmt.Printf("Set `export GO_DISCOVERY_CONFIG_DYNAMIC=%q` to enable experiments.\n", p)
    return nil
}