feat: replace "azurerm_sql_failover_group" with "azurerm_mssql_failov…

…er_group"

The resource "azurerm_sql_failover_group" has been deprecated and is removed in the next
version of the AzureRM provider. In order to prepare for this, we are replacing it with
the new alternative "azurerm_mssql_failover_group". Because OpenTofu will run the delete
of "azurerm_sql_failover_group" in parallel with the creation of "azurerm_mssql_failover_group",
we need to create a resource with a different name so that Azure does not fail with
a name conflict error.

- Whether or not `instance_name` is set, a `-g` will be appended to the name of the failover
  group in Azure
- Because the name of the failover group has changed, existing bindings will cease to work,
  and apps must be rebound and restaged.

acceptance-tests/helpers/apps/http.go

@@ -34,6 +34,16 @@ func (a *App) GET(format string, s ...any) string {
 	return string(data)
 }
 
+func (a *App) GETResponse(format string, s ...any) *http.Response {
+	GinkgoHelper()
+
+	url := a.urlf(format, s...)
+	GinkgoWriter.Printf("HTTP GET: %s\n", url)
+	response, err := http.Get(url)
+	Expect(err).NotTo(HaveOccurred())
+	return response
+}
+
 func (a *App) PUT(data, format string, s ...any) {
 	url := a.urlf(format, s...)
 	GinkgoWriter.Printf("HTTP PUT: %s\n", url)

acceptance-tests/mssql_server_pair_and_fog_db_test.go

@@ -2,6 +2,7 @@ package acceptance_test
 
 import (
 	"context"
+	"fmt"
 
 	"csbbrokerpakazure/acceptance-tests/helpers/apps"
 	"csbbrokerpakazure/acceptance-tests/helpers/brokers"
@@ -96,9 +97,11 @@ var _ = Describe("MSSQL Server Pair and Failover Group DB", Label("mssql-db-fail
 			runFailoverServicePlan,
 			services.WithBroker(serviceBroker),
 			services.WithParameters(map[string]any{
-				"server_pair_name":  serversConfig.ServerPairTag,
-				"server_pairs":      serversConfig.ServerPairsConfig(),
-				"fog_instance_name": fogName,
+				"server_pair_name": serversConfig.ServerPairTag,
+				"server_pairs":     serversConfig.ServerPairsConfig(),
+				// We now append a "-g" to the instance name as we replace the "azurerm_sql_failover_group"
+				// resource with the "azurerm_mssql_failover_group" to avoid name clashes.
+				"fog_instance_name": fmt.Sprintf("%s-g", fogName),
 			}),
 			services.WithName(serviceNameStandard),
 		)

acceptance-tests/upgrade/update_and_upgrade_mssql_db_failover_group_test.go

@@ -2,6 +2,7 @@ package upgrade_test
 
 import (
 	"context"
+	"net/http"
 
 	"csbbrokerpakazure/acceptance-tests/helpers/apps"
 	"csbbrokerpakazure/acceptance-tests/helpers/brokers"
@@ -50,7 +51,7 @@ var _ = Describe("UpgradeMssqlDBFailoverGroupTest", Label("mssql-db-failover-gro
 			// is cleaned up regardless as to whether it wa successful. This is important when we use our own service broker
 			// (which can only have 5 instances at any time) to prevent subsequent test failures.
 			defer services.Delete(serviceName)
-			fogConfig := failoverGroupConfig(serversConfig.ServerPairTag)
+			fogConfig := newFailoverGroupConfig(serversConfig.ServerPairTag)
 			initialFogInstance := services.CreateInstance(
 				serviceOffering,
 				servicePlan,
@@ -65,8 +66,8 @@ var _ = Describe("UpgradeMssqlDBFailoverGroupTest", Label("mssql-db-failover-gro
 			defer apps.Delete(appOne, appTwo)
 
 			By("binding to the apps")
-			initialFogInstance.Bind(appOne)
-			initialFogInstance.Bind(appTwo)
+			bindingOne := initialFogInstance.Bind(appOne)
+			bindingTwo := initialFogInstance.Bind(appTwo)
 
 			By("starting the apps")
 			apps.Start(appOne, appTwo)
@@ -93,17 +94,37 @@ var _ = Describe("UpgradeMssqlDBFailoverGroupTest", Label("mssql-db-failover-gro
 			By("upgrading previous services")
 			initialFogInstance.Upgrade()
 
+			// When the "azurerm_sql_failover_group" resource is updated to the "azurerm_mssql_failover_group" resource,
+			// the name of the FOG has to be changed (to avoid name clashes), resulting in the URL of the FOG
+			// changing. This means that existing bindings do not work, and apps need to be re-bound.
+			// At some stage this behavior will change, and this check and the subsequent re-bind can be removed.
+			By("observing that existing bindings do not work")
+			resp := appTwo.GETResponse("%s/%s", schema, keyOne)
+			Expect(resp).To(HaveHTTPStatus(http.StatusInternalServerError))
+			Expect(resp).To(HaveHTTPBody(MatchRegexp(`error preparing statement:.*no such host`)))
+
+			By("re-binding and re-staging the apps")
+			bindingOne.Unbind()
+			bindingTwo.Unbind()
+			initialFogInstance.Bind(appOne)
+			initialFogInstance.Bind(appTwo)
+			apps.Restage(appOne, appTwo)
+
 			By("getting the previously set value using the second app")
 			got = appTwo.GET("%s/%s", schema, keyOne)
 			Expect(got).To(Equal(valueOne))
 
-			By("updating the instance plan")
-			initialFogInstance.Update("-p", "medium")
+			By("updating the instance")
+			initialFogInstance.Update("-c", "{}")
 
 			By("getting the previously set value using the second app")
 			got = appTwo.GET("%s/%s", schema, keyOne)
 			Expect(got).To(Equal(valueOne))
 
+			// We now append a "-g" to the instance name as we replace the "azurerm_sql_failover_group"
+			// resource with the "azurerm_mssql_failover_group" to avoid name clashes.
+			fogConfig.InstanceName += "-g"
+
 			By("connecting to the existing failover group")
 			const servicePlanExisting = "existing"
 			serviceNameExisting := random.Name(random.WithPrefix(serviceOffering, servicePlanExisting))
@@ -119,9 +140,9 @@ var _ = Describe("UpgradeMssqlDBFailoverGroupTest", Label("mssql-db-failover-gro
 			By("purging the initial FOG instance")
 			initialFogInstance.Purge()
 
-			By("creating new bindings and testing they still work")
-			bindingOne := dbFogInstance.Bind(appOne)
-			bindingTwo := dbFogInstance.Bind(appTwo)
+			By("creating new bindings using the 'existing' plan")
+			bindingOne = dbFogInstance.Bind(appOne)
+			bindingTwo = dbFogInstance.Bind(appTwo)
 			apps.Restage(appOne, appTwo)
 			defer bindingOne.Unbind()
 			defer bindingTwo.Unbind()
@@ -143,10 +164,16 @@ var _ = Describe("UpgradeMssqlDBFailoverGroupTest", Label("mssql-db-failover-gro
 	})
 })
 
-func failoverGroupConfig(serverPairTag string) map[string]string {
-	return map[string]string{
-		"instance_name": random.Name(random.WithPrefix("fog")),
-		"db_name":       random.Name(random.WithPrefix("db")),
-		"server_pair":   serverPairTag,
+type failoverGroupConfig struct {
+	InstanceName  string `json:"instance_name"`
+	DBName        string `json:"db_name"`
+	ServerPairTag string `json:"server_pair"`
+}
+
+func newFailoverGroupConfig(serverPairTag string) failoverGroupConfig {
+	return failoverGroupConfig{
+		InstanceName:  random.Name(random.WithPrefix("fog")),
+		DBName:        random.Name(random.WithPrefix("db")),
+		ServerPairTag: serverPairTag,
 	}
 }

azure-mssql-db-failover-group.yml

@@ -70,7 +70,7 @@ provision:
     details: Maximum storage allocated to the database instance in GB
   - field_name: instance_name
     type: string
-    details: Name for your Azure SQL Failover Group
+    details: Name for your Azure SQL Failover Group. Note that the resource name in Azure will have "-g" appended.
     default: csb-azsql-fog-${request.instance_id}
     constraints:
       maxLength: 63

terraform/azure-mssql-db-failover/mssql-db-fog-main.tf

@@ -40,12 +40,15 @@ resource "azurerm_mssql_database" "secondary_db" {
   count                       = var.existing ? 0 : 1
 }
 
-resource "azurerm_sql_failover_group" "failover_group" {
-  name                = var.instance_name
-  resource_group_name = var.server_credential_pairs[var.server_pair].primary.resource_group
-  server_name         = data.azurerm_mssql_server.primary_sql_db_server.name
-  databases           = [azurerm_mssql_database.primary_db[count.index].id]
-  partner_servers {
+resource "azurerm_mssql_failover_group" "failover_group" {
+  # When switching from the "azurerm_sql_failover_group" to the "azurerm_mssql_failover_group"
+  # resource type, it's necessary to use a different name to prevent name clashes, so we add
+  # the suffix "-g" just to get a different name.
+  name = format("%s-g", var.instance_name)
+
+  server_id = data.azurerm_mssql_server.primary_sql_db_server.id
+  databases = [azurerm_mssql_database.primary_db[count.index].id]
+  partner_server {
     id = data.azurerm_mssql_server.secondary_sql_db_server.id
   }
 

terraform/azure-mssql-db-failover/mssql-db-fog-outputs.tf

@@ -3,8 +3,8 @@
 locals {
   primary_db_name = (length(azurerm_mssql_database.primary_db) > 0 ? azurerm_mssql_database.primary_db[0].name : "")
   primary_db_id   = (length(azurerm_mssql_database.primary_db) > 0 ? azurerm_mssql_database.primary_db[0].id : "")
-  fog_name        = (length(azurerm_sql_failover_group.failover_group) > 0 ? azurerm_sql_failover_group.failover_group[0].name : "")
-  fog_id          = (length(azurerm_sql_failover_group.failover_group) > 0 ? azurerm_sql_failover_group.failover_group[0].id : "")
+  fog_name        = (length(azurerm_mssql_failover_group.failover_group) > 0 ? azurerm_mssql_failover_group.failover_group[0].name : "")
+  fog_id          = (length(azurerm_mssql_failover_group.failover_group) > 0 ? azurerm_mssql_failover_group.failover_group[0].id : "")
 }
 
 output "sqldbName" { value = var.existing ? var.db_name : local.primary_db_name }