Investigate and fix flaky sql user test.

This test fails for a few reasons: one, there are persistent quota
and service-unavailable errors with the second-gen SQL instances.
Two, the issue mentioned in #1184, that there's unspecified behavior
in tests where two resources have the same ID.  This changes the ID
to be user/host/instance instead of user/instance, and adds 429/503
handling to the sqladminOperationWait().

google/resource_sql_user.go

@@ -87,7 +87,7 @@ func resourceSqlUserCreate(d *schema.ResourceData, meta interface{}) error {
 			"user %s into instance %s: %s", name, instance, err)
 	}
 
-	d.SetId(fmt.Sprintf("%s/%s", instance, name))
+	d.SetId(fmt.Sprintf("%s/%s/%s", user.Name, user.Host, user.Instance))
 
 	err = sqladminOperationWait(config, op, project, "Insert User")
 
@@ -109,7 +109,7 @@ func resourceSqlUserRead(d *schema.ResourceData, meta interface{}) error {
 
 	instance := d.Get("instance").(string)
 	name := d.Get("name").(string)
-	host := d.Get("host").(string)
+	host, hostOk := d.GetOk("host")
 
 	users, err := config.clientSqlAdmin.Users.List(project, instance).Do()
 
@@ -119,7 +119,7 @@ func resourceSqlUserRead(d *schema.ResourceData, meta interface{}) error {
 
 	var user *sqladmin.User
 	for _, currentUser := range users.Items {
-		if currentUser.Name == name && currentUser.Host == host {
+		if currentUser.Name == name && (!hostOk || currentUser.Host == host.(string)) {
 			user = currentUser
 			break
 		}
@@ -136,6 +136,7 @@ func resourceSqlUserRead(d *schema.ResourceData, meta interface{}) error {
 	d.Set("instance", user.Instance)
 	d.Set("name", user.Name)
 	d.Set("project", project)
+	d.SetId(fmt.Sprintf("%s/%s/%s", user.Name, user.Host, user.Instance))
 	return nil
 }
 
@@ -225,7 +226,6 @@ func resourceSqlUserImporter(d *schema.ResourceData, meta interface{}) ([]*schem
 		d.Set("instance", parts[0])
 		d.Set("host", parts[1])
 		d.Set("name", parts[2])
-		d.SetId(fmt.Sprintf("%s/%s", parts[0], parts[2]))
 	} else {
 		return nil, fmt.Errorf("Invalid specifier. Expecting {instance}/{name} for 2nd generation instance and {instance}/{host}/{name} for 1st generation instance")
 	}

google/resource_sql_user_test.go

@@ -68,6 +68,7 @@ func TestAccSqlUser_secondGen(t *testing.T) {
 			},
 			resource.TestStep{
 				ResourceName:            "google_sql_user.user",
+				ImportStateId:           instance + "/admin",
 				ImportState:             true,
 				ImportStateVerify:       true,
 				ImportStateVerifyIgnore: []string{"password"},

google/sqladmin_operation.go

@@ -2,11 +2,13 @@ package google
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"log"
 	"time"
 
 	"github.com/hashicorp/terraform/helper/resource"
+	"google.golang.org/api/googleapi"
 	"google.golang.org/api/sqladmin/v1beta4"
 )
 
@@ -20,10 +22,23 @@ func (w *SqlAdminOperationWaiter) RefreshFunc() resource.StateRefreshFunc {
 	return func() (interface{}, string, error) {
 		var op *sqladmin.Operation
 		var err error
+		backoff := 1 * time.Second
 
 		log.Printf("[DEBUG] self_link: %s", w.Op.SelfLink)
-		op, err = w.Service.Operations.Get(w.Project, w.Op.Name).Do()
-
+		for {
+			op, err = w.Service.Operations.Get(w.Project, w.Op.Name).Do()
+
+			if e, ok := err.(*googleapi.Error); ok && (e.Code == 429 || e.Code == 503) {
+				backoff = backoff * 2
+				if backoff > 30*time.Second {
+					return nil, "", errors.New("Too many quota / service unavailable errors waiting for operation.")
+				}
+				time.Sleep(backoff)
+				continue
+			} else {
+				break
+			}
+		}
 		if err != nil {
 			return nil, "", err
 		}