user_agent.go

// Copyright 2023 Google LLC
//
// 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 platform

import (
	"fmt"
	"html/template"
	"strings"

	"github.com/GoogleCloudPlatform/ops-agent/internal/version"
)

var versionLabelTemplate = template.Must(template.New("versionlabel").Parse(`{{.Prefix}}/{{.AgentVersion}}-{{.BuildDistro}}`))
var userAgentTemplate = template.Must(template.New("useragent").Parse(`{{.Prefix}}/{{.AgentVersion}} (BuildDistro={{.BuildDistro}};Platform={{.Platform}};ShortName={{.ShortName}};ShortVersion={{.ShortVersion}})`))

func expandTemplate(t *template.Template, prefix string, extraParams map[string]string) (string, error) {
	params := map[string]string{
		"Prefix":       prefix,
		"AgentVersion": version.Version,
		"BuildDistro":  version.BuildDistro,
	}
	for k, v := range extraParams {
		params[k] = v
	}
	var b strings.Builder
	if err := t.Execute(&b, params); err != nil {
		fmt.Println(err.Error())
		return "", err
	}
	return b.String(), nil
}

func (p Platform) VersionLabel(prefix string) (string, error) {
	return expandTemplate(versionLabelTemplate, prefix, nil)
}

func (p Platform) UserAgent(prefix string) (string, error) {
	extraParams := map[string]string{
		"Platform":     p.HostInfo.OS,
		"ShortName":    p.HostInfo.Platform,
		"ShortVersion": p.HostInfo.PlatformVersion,
	}
	return expandTemplate(userAgentTemplate, prefix, extraParams)
}