Create temporary file with Google credential for terraformcloud (#249)

* feat: create temporary file containing Google credentials

* error comment format added

Co-authored-by: Jérémy Levilain <[email protected]>
Co-authored-by: Felipe Reyes <[email protected]>
Co-authored-by: chris-minka <[email protected]>

Author: 4 people

postgresql/provider.go

@@ -3,10 +3,12 @@ package postgresql
 import (
 	"context"
 	"fmt"
+	"os"
 
 	"github.com/blang/semver"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/validation"
+	"golang.org/x/oauth2/google"
 
 	"github.com/aws/aws-sdk-go-v2/aws"
 	awsConfig "github.com/aws/aws-sdk-go-v2/config"
@@ -210,6 +212,30 @@ func getRDSAuthToken(region string, profile string, username string, host string
 	return token, err
 }
 
+func createGoogleCredsFileIfNeeded() error {
+	if _, err := google.FindDefaultCredentials(context.Background()); err == nil {
+		return nil
+	}
+
+	rawGoogleCredentials := os.Getenv("GOOGLE_CREDENTIALS")
+	if rawGoogleCredentials == "" {
+		return nil
+	}
+
+	tmpFile, err := os.CreateTemp("", "")
+	if err != nil {
+		return fmt.Errorf("could not create temporary file: %w", err)
+	}
+	defer tmpFile.Close()
+
+	_, err = tmpFile.WriteString(rawGoogleCredentials)
+	if err != nil {
+		return fmt.Errorf("could not write in temporary file: %w", err)
+	}
+
+	return os.Setenv("GOOGLE_APPLICATION_CREDENTIALS", tmpFile.Name())
+}
+
 func providerConfigure(d *schema.ResourceData) (interface{}, error) {
 	var sslMode string
 	if sslModeRaw, ok := d.GetOk("sslmode"); ok {
@@ -265,6 +291,12 @@ func providerConfigure(d *schema.ResourceData) (interface{}, error) {
 		}
 	}
 
+	if config.Scheme == "gcppostgres" {
+		if err := createGoogleCredsFileIfNeeded(); err != nil {
+			return nil, err
+		}
+	}
+
 	client := config.NewClient(d.Get("database").(string))
 	return client, nil
 }