pulumi/pkg/authhelpers/gcpauth.go

108 lines
3.7 KiB
Go

// Copyright 2019-2024, Pulumi Corporation.
//
// 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 authhelpers
import (
"context"
"encoding/json"
"fmt"
"os"
"cloud.google.com/go/storage"
"golang.org/x/oauth2"
"golang.org/x/oauth2/google"
"gocloud.dev/blob/gcsblob"
"gocloud.dev/blob"
"gocloud.dev/gcp"
)
type GoogleCredentials struct {
PrivateKeyID string `json:"private_key_id"`
PrivateKey string `json:"private_key"`
ClientEmail string `json:"client_email"`
ClientID string `json:"client_id"`
}
// ResolveGoogleCredentials loads the google credentials using the pulumi-specific
// logic first, falling back to the DefaultCredentials resoulution after.
func ResolveGoogleCredentials(ctx context.Context, scope string) (*google.Credentials, error) {
// GOOGLE_CREDENTIALS aren't part of the gcloud standard authorization variables
// but the GCP terraform provider uses this variable to allow users to authenticate
// with the contents of a credentials.json file instead of just a file path.
// https://www.terraform.io/docs/backends/types/gcs.html
if creds := os.Getenv("GOOGLE_CREDENTIALS"); creds != "" {
// We try $GOOGLE_CREDENTIALS before gcp.DefaultCredentials
// so that users can override the default creds
credentials, err := google.CredentialsFromJSON(ctx, []byte(creds), scope)
if err != nil {
return nil, fmt.Errorf("unable to parse credentials from $GOOGLE_CREDENTIALS: %w", err)
}
return credentials, nil
}
// GOOGLE_OAUTH_ACCESS_TOKEN isnt't part of the gcloud standard authorization variables
// but the GCP terraform provider uses this variable to allow users to authenticate
// with a temporary access token obtained from the Google Authorization Server instead
// of just a file path or credentials.json.
// https://www.terraform.io/docs/backends/types/gcs.html
if creds := os.Getenv("GOOGLE_OAUTH_ACCESS_TOKEN"); creds != "" {
// We try $GOOGLE_OAUTH_ACCESS_TOKEN before gcp.DefaultCredentials
// so that users can override the default creds
return &google.Credentials{
TokenSource: oauth2.StaticTokenSource(&oauth2.Token{AccessToken: creds}),
}, nil
}
// DefaultCredentials will attempt to load creds in the following order:
// 1. a file located at $GOOGLE_APPLICATION_CREDENTIALS
// 2. application_default_credentials.json file in ~/.config/gcloud or $APPDATA\gcloud
credentials, err := gcp.DefaultCredentials(ctx)
if err != nil {
return nil, fmt.Errorf("unable to find gcp credentials: %w", err)
}
return credentials, nil
}
func GoogleCredentialsMux(ctx context.Context) (*blob.URLMux, error) {
credentials, err := ResolveGoogleCredentials(ctx, storage.ScopeReadWrite)
if err != nil {
return nil, fmt.Errorf("missing google credentials: %w", err)
}
client, err := gcp.NewHTTPClient(gcp.DefaultTransport(), credentials.TokenSource)
if err != nil {
return nil, err
}
options := gcsblob.Options{}
account := GoogleCredentials{}
err = json.Unmarshal(credentials.JSON, &account)
if err == nil && account.ClientEmail != "" && account.PrivateKey != "" {
options.GoogleAccessID = account.ClientEmail
options.PrivateKey = []byte(account.PrivateKey)
}
blobmux := &blob.URLMux{}
blobmux.RegisterBucket(gcsblob.Scheme, &gcsblob.URLOpener{
Client: client,
Options: options,
})
return blobmux, nil
}