Add OAuth2 access_token and client config as credential options. (#2838)

Signed-off-by: Modular Magician <magic-modules@google.com>

google/config.go

@@ -2,11 +2,9 @@ package google
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"log"
 	"net/http"
-	"strings"
 
 	"github.com/hashicorp/terraform/helper/logging"
 	"github.com/hashicorp/terraform/helper/pathorcontents"
@@ -14,8 +12,7 @@ import (
 	"github.com/terraform-providers/terraform-provider-google/version"
 
 	"golang.org/x/oauth2"
-	"golang.org/x/oauth2/google"
-	"golang.org/x/oauth2/jwt"
+	googleoauth "golang.org/x/oauth2/google"
 	appengine "google.golang.org/api/appengine/v1"
 	"google.golang.org/api/bigquery/v2"
 	"google.golang.org/api/cloudbilling/v1"
@@ -53,6 +50,7 @@ import (
 // provider.
 type Config struct {
 	Credentials string
+	AccessToken string
 	Project     string
 	Region      string
 	Zone        string
@@ -98,7 +96,6 @@ type Config struct {
 }
 
 func (c *Config) loadAndValidate() error {
-	var account accountFile
 	clientScopes := []string{
 		"https://www.googleapis.com/auth/compute",
 		"https://www.googleapis.com/auth/cloud-platform",
@@ -106,55 +103,13 @@ func (c *Config) loadAndValidate() error {
 		"https://www.googleapis.com/auth/devstorage.full_control",
 	}
 
-	var client *http.Client
-	var tokenSource oauth2.TokenSource
-
-	if c.Credentials != "" {
-		contents, _, err := pathorcontents.Read(c.Credentials)
-		if err != nil {
-			return fmt.Errorf("Error loading credentials: %s", err)
-		}
-
-		// Assume account_file is a JSON string
-		if err := parseJSON(&account, contents); err != nil {
-			return fmt.Errorf("Error parsing credentials '%s': %s", contents, err)
-		}
-
-		// Get the token for use in our requests
-		log.Printf("[INFO] Requesting Google token...")
-		log.Printf("[INFO]   -- Email: %s", account.ClientEmail)
-		log.Printf("[INFO]   -- Scopes: %s", clientScopes)
-		log.Printf("[INFO]   -- Private Key Length: %d", len(account.PrivateKey))
-
-		conf := jwt.Config{
-			Email:      account.ClientEmail,
-			PrivateKey: []byte(account.PrivateKey),
-			Scopes:     clientScopes,
-			TokenURL:   "https://accounts.google.com/o/oauth2/token",
-		}
-
-		// Initiate an http.Client. The following GET request will be
-		// authorized and authenticated on the behalf of
-		// your service account.
-		client = conf.Client(context.Background())
-
-		tokenSource = conf.TokenSource(context.Background())
-	} else {
-		log.Printf("[INFO] Authenticating using DefaultClient")
-		err := error(nil)
-		client, err = google.DefaultClient(context.Background(), clientScopes...)
-		if err != nil {
-			return err
-		}
-
-		tokenSource, err = google.DefaultTokenSource(context.Background(), clientScopes...)
-		if err != nil {
-			return err
-		}
+	tokenSource, err := c.getTokenSource(clientScopes)
+	if err != nil {
+		return err
 	}
-
 	c.tokenSource = tokenSource
 
+	client := oauth2.NewClient(context.Background(), tokenSource)
 	client.Transport = logging.NewTransport("Google", client.Transport)
 
 	terraformVersion := httpclient.UserAgentString()
@@ -165,8 +120,6 @@ func (c *Config) loadAndValidate() error {
 	c.client = client
 	c.userAgent = userAgent
 
-	var err error
-
 	log.Printf("[INFO] Instantiating GCE client...")
 	c.clientCompute, err = compute.New(client)
 	if err != nil {
@@ -391,17 +344,31 @@ func (c *Config) loadAndValidate() error {
 	return nil
 }
 
-// accountFile represents the structure of the account file JSON file.
-type accountFile struct {
-	PrivateKeyId string `json:"private_key_id"`
-	PrivateKey   string `json:"private_key"`
-	ClientEmail  string `json:"client_email"`
-	ClientId     string `json:"client_id"`
-}
+func (c *Config) getTokenSource(clientScopes []string) (oauth2.TokenSource, error) {
+	if c.AccessToken != "" {
+		log.Printf("[INFO] Using configured Google access token (length %d)", len(c.AccessToken))
+		log.Printf("[INFO]   -- Scopes: %s", clientScopes)
+		token := &oauth2.Token{AccessToken: c.AccessToken}
+		return oauth2.StaticTokenSource(token), nil
+	}
 
-func parseJSON(result interface{}, contents string) error {
-	r := strings.NewReader(contents)
-	dec := json.NewDecoder(r)
+	if c.Credentials != "" {
+		contents, _, err := pathorcontents.Read(c.Credentials)
+		if err != nil {
+			return nil, fmt.Errorf("Error loading credentials: %s", err)
+		}
 
-	return dec.Decode(result)
+		creds, err := googleoauth.CredentialsFromJSON(context.Background(), []byte(contents), clientScopes...)
+		if err != nil {
+			return nil, fmt.Errorf("Unable to parse credentials from '%s': %s", contents, err)
+		}
+
+		log.Printf("[INFO] Requesting Google token using Credential File %q...", c.Credentials)
+		log.Printf("[INFO]   -- Scopes: %s", clientScopes)
+		return creds.TokenSource, nil
+	}
+
+	log.Printf("[INFO] Authenticating using DefaultClient")
+	log.Printf("[INFO]   -- Scopes: %s", clientScopes)
+	return googleoauth.DefaultTokenSource(context.Background(), clientScopes...)
 }

google/config_test.go

@@ -48,3 +48,18 @@ func TestConfigLoadAndValidate_accountFileJSONInvalid(t *testing.T) {
 		t.Fatalf("expected error, but got nil")
 	}
 }
+
+func TestConfigLoadValidate_accessToken(t *testing.T) {
+	accessToken := getTestAccessTokenFromEnv(t)
+
+	config := Config{
+		AccessToken: accessToken,
+		Project:     "my-gce-project",
+		Region:      "us-central1",
+	}
+
+	err := config.loadAndValidate()
+	if err != nil {
+		t.Fatalf("error: %v", err)
+	}
+}

google/provider.go

@@ -1,13 +1,15 @@
 package google
 
 import (
-	"encoding/json"
+	"context"
 	"fmt"
 	"os"
 
 	"github.com/hashicorp/terraform/helper/mutexkv"
 	"github.com/hashicorp/terraform/helper/schema"
 	"github.com/hashicorp/terraform/terraform"
+
+	googleoauth "golang.org/x/oauth2/google"
 )
 
 // Global MutexKV
@@ -28,6 +30,12 @@ func Provider() terraform.ResourceProvider {
 				ValidateFunc: validateCredentials,
 			},
 
+			"access_token": {
+				Type:          schema.TypeString,
+				Optional:      true,
+				ConflictsWith: []string{"credentials"},
+			},
+
 			"project": {
 				Type:     schema.TypeString,
 				Optional: true,
@@ -244,12 +252,17 @@ func ResourceMapWithErrors() (map[string]*schema.Resource, error) {
 }
 
 func providerConfigure(d *schema.ResourceData) (interface{}, error) {
-	credentials := d.Get("credentials").(string)
 	config := Config{
-		Credentials: credentials,
-		Project:     d.Get("project").(string),
-		Region:      d.Get("region").(string),
-		Zone:        d.Get("zone").(string),
+		Project: d.Get("project").(string),
+		Region:  d.Get("region").(string),
+		Zone:    d.Get("zone").(string),
+	}
+
+	// Add credential source
+	if v, ok := d.GetOk("access_token"); ok {
+		config.AccessToken = v.(string)
+	} else if v, ok := d.GetOk("credentials"); ok {
+		config.Credentials = v.(string)
 	}
 
 	if err := config.loadAndValidate(); err != nil {
@@ -268,10 +281,9 @@ func validateCredentials(v interface{}, k string) (warnings []string, errors []e
 	if _, err := os.Stat(creds); err == nil {
 		return
 	}
-	var account accountFile
-	if err := json.Unmarshal([]byte(creds), &account); err != nil {
+	if _, err := googleoauth.CredentialsFromJSON(context.Background(), []byte(creds)); err != nil {
 		errors = append(errors,
-			fmt.Errorf("credentials are not valid JSON '%s': %s", creds, err))
+			fmt.Errorf("JSON credentials in %q are not valid: %s", creds, err))
 	}
 
 	return

google/provider_test.go

@@ -57,6 +57,10 @@ var billingAccountEnvVars = []string{
 	"GOOGLE_BILLING_ACCOUNT",
 }
 
+var accessTokenEnvVars = []string{
+	"GOOGLE_OAUTH2_ACCESS_TOKEN",
+}
+
 func init() {
 	testAccProvider = Provider().(*schema.Provider)
 	testAccRandomProvider = random.Provider().(*schema.Provider)
@@ -202,6 +206,11 @@ func getTestServiceAccountFromEnv(t *testing.T) string {
 	return multiEnvSearch(serviceAccountEnvVars)
 }
 
+func getTestAccessTokenFromEnv(t *testing.T) string {
+	skipIfEnvNotSet(t, accessTokenEnvVars...)
+	return multiEnvSearch(accessTokenEnvVars)
+}
+
 func multiEnvSearch(ks []string) string {
 	for _, k := range ks {
 		if v := os.Getenv(k); v != "" {