azurerm_api_management_policy - fixes an error caused by a migration

internal/services/apimanagement/api_management_gateway_api_resource.go

@@ -41,7 +41,7 @@ func resourceApiManagementGatewayApi() *pluginsdk.Resource {
 
 		SchemaVersion: 1,
 		StateUpgraders: pluginsdk.StateUpgrades(map[int]pluginsdk.StateUpgrade{
-			0: migration.ApiManagementApiPolicyV0ToV1{},
+			0: migration.ApiManagementGatewayApiV0ToV1{},
 		}),
 
 		Schema: map[string]*pluginsdk.Schema{

internal/services/apimanagement/api_management_policy_resource.go

@@ -31,10 +31,11 @@ func resourceApiManagementPolicy() *pluginsdk.Resource {
 			return err
 		}),
 
-		SchemaVersion: 2,
+		SchemaVersion: 3,
 		StateUpgraders: pluginsdk.StateUpgrades(map[int]pluginsdk.StateUpgrade{
 			0: migration.ApiManagementPolicyV0ToV1{},
 			1: migration.ApiManagementPolicyV1ToV2{},
+			2: migration.ApiManagementPolicyV2ToV3{},
 		}),
 
 		Timeouts: &pluginsdk.ResourceTimeout{

internal/services/apimanagement/migration/gateway_api_v0_to_v1.go

@@ -0,0 +1,34 @@
+package migration
+
+import (
+	"context"
+
+	"github.com/hashicorp/terraform-provider-azurerm/internal/tf/pluginsdk"
+)
+
+var _ pluginsdk.StateUpgrade = ApiManagementGatewayApiV0ToV1{}
+
+type ApiManagementGatewayApiV0ToV1 struct{}
+
+func (ApiManagementGatewayApiV0ToV1) Schema() map[string]*pluginsdk.Schema {
+	return map[string]*pluginsdk.Schema{
+		"api_id": {
+			Type:     pluginsdk.TypeString,
+			Required: true,
+			ForceNew: true,
+		},
+		"gateway_id": {
+			Type:     pluginsdk.TypeString,
+			Required: true,
+			ForceNew: true,
+		},
+	}
+}
+
+// UpgradeFunc this is a noop migration to account for a migration that was accidentally added from github.com/hashicorp/terraform-provider-azurerm/pull/22783/
+// That migration didn't do anything for this resource so we'll just swap it for a no-op migration here
+func (ApiManagementGatewayApiV0ToV1) UpgradeFunc() pluginsdk.StateUpgraderFunc {
+	return func(ctx context.Context, rawState map[string]interface{}, meta interface{}) (map[string]interface{}, error) {
+		return rawState, nil
+	}
+}

internal/services/apimanagement/migration/policy_v1_to_v2.go

@@ -13,9 +13,28 @@ var _ pluginsdk.StateUpgrade = ApiManagementPolicyV1ToV2{}
 type ApiManagementPolicyV1ToV2 struct{}
 
 func (ApiManagementPolicyV1ToV2) Schema() map[string]*pluginsdk.Schema {
-	return policySchemaForV0AndV1()
+	return map[string]*pluginsdk.Schema{
+		"api_management_id": {
+			Type:     pluginsdk.TypeString,
+			Required: true,
+			ForceNew: true,
+		},
+
+		"xml_content": {
+			Type:     pluginsdk.TypeString,
+			Optional: true,
+			Computed: true,
+		},
+
+		"xml_link": {
+			Type:     pluginsdk.TypeString,
+			Optional: true,
+		},
+	}
 }
 
+// UpgradeFunc this migration doesn't do anything as `/policies/xml` is never the suffix for this but I don't believe we can remove it as we need it go from one migration
+// to the next
 func (ApiManagementPolicyV1ToV2) UpgradeFunc() pluginsdk.StateUpgraderFunc {
 	return func(ctx context.Context, rawState map[string]interface{}, meta interface{}) (map[string]interface{}, error) {
 		// old id : /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/group1/providers/Microsoft.ApiManagement/service/instance1/policies/policy

internal/services/apimanagement/migration/policy_v2_to_v3.go

@@ -0,0 +1,48 @@
+package migration
+
+import (
+	"context"
+	"log"
+	"strings"
+
+	"github.com/hashicorp/terraform-provider-azurerm/internal/tf/pluginsdk"
+)
+
+var _ pluginsdk.StateUpgrade = ApiManagementPolicyV2ToV3{}
+
+type ApiManagementPolicyV2ToV3 struct{}
+
+func (ApiManagementPolicyV2ToV3) Schema() map[string]*pluginsdk.Schema {
+	return map[string]*pluginsdk.Schema{
+		"api_management_id": {
+			Type:     pluginsdk.TypeString,
+			Required: true,
+			ForceNew: true,
+		},
+
+		"xml_content": {
+			Type:     pluginsdk.TypeString,
+			Optional: true,
+			Computed: true,
+		},
+
+		"xml_link": {
+			Type:     pluginsdk.TypeString,
+			Optional: true,
+		},
+	}
+}
+
+func (ApiManagementPolicyV2ToV3) UpgradeFunc() pluginsdk.StateUpgraderFunc {
+	return func(ctx context.Context, rawState map[string]interface{}, meta interface{}) (map[string]interface{}, error) {
+		// old id : /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/group1/providers/Microsoft.ApiManagement/service/instance1/policies/policy
+		// new id : /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/group1/providers/Microsoft.ApiManagement/service/instance1
+		oldId := rawState["id"].(string)
+		newId := strings.TrimSuffix(oldId, "/policies/policy")
+
+		log.Printf("[DEBUG] Updating ID from %q to %q", oldId, newId)
+		rawState["id"] = newId
+
+		return rawState, nil
+	}
+}