image/resources/netapp-exports/secrets.go

/*
 Copyright 2022 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

      https://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 main

import (
	"context"
	"errors"
	"fmt"
	"log"
	"unicode/utf8"

	secretmanager "cloud.google.com/go/secretmanager/apiv1"
	"google.golang.org/api/transport"
	secretmanagerpb "google.golang.org/genproto/googleapis/cloud/secretmanager/v1"
)

type GCPSecret struct {
	ServiceAccountKey string `hcl:"service_account_key,optional"`
	Project           string `hcl:"project,optional"`
	Name              string `hcl:"name"`
	Version           string `hcl:"version,optional"`
}

var cachedProjectID = ""

func (s *GCPSecret) validate() error {
	if s.Name == "" {
		return errors.New("name required for Google Cloud Secret")
	}
	return nil
}

func (s *GCPSecret) fullName(ctx context.Context) (string, error) {
	name := s.Name
	if name == "" {
		return "", errors.New("secret name not set")
	}

	project := s.Project
	if project == "" {
		var err error
		project, err = projectIDFromEnvironment(ctx)
		if err != nil {
			return "", err
		}
		log.Printf("Resolved project ID as %s\n", project)
	}

	version := s.Version
	if version == "" {
		version = "latest"
	}

	fullName := fmt.Sprintf(
		"projects/%s/secrets/%s/versions/%s",
		project, name, version)

	return fullName, nil
}

func (s *GCPSecret) get(ctx context.Context) (string, error) {
	client, err := secretmanager.NewClient(ctx)
	if err != nil {
		return "", err
	}
	defer client.Close()

	name, err := s.fullName(ctx)
	if err != nil {
		return "", err
	}

	request := &secretmanagerpb.AccessSecretVersionRequest{
		Name: name,
	}

	response, err := client.AccessSecretVersion(ctx, request)
	if err != nil {
		return "", err
	}

	data := response.GetPayload().GetData()
	if data == nil {
		return "", errors.New("secret did not contain any data")
	}

	if !utf8.Valid(data) {
		return "", errors.New("secret is not valid UTF8")
	}

	return string(data), nil
}

func projectIDFromEnvironment(ctx context.Context) (string, error) {
	if cachedProjectID != "" {
		return cachedProjectID, nil
	}

	creds, err := transport.Creds(ctx)
	if err != nil {
		return "", fmt.Errorf("could not get project ID from environment: %w", err)
	}

	project := creds.ProjectID
	if project == "" {
		return "", fmt.Errorf("could not get project ID from environment")
	}

	cachedProjectID = project
	return project, nil
}