only allow instance templates with 375gb scratch disks (#2495)

GoogleCloudPlatform · Oct 24, 2019 · ae81037 · ae81037
1 parent e9e46bf
commit ae81037
Show file tree

Hide file tree

Showing 4 changed files with 63 additions and 0 deletions.
diff --git a/third_party/terraform/resources/resource_compute_instance_template.go b/third_party/terraform/resources/resource_compute_instance_template.go
@@ -522,6 +522,11 @@ func resourceComputeInstanceTemplateSourceImageCustomizeDiff(diff *schema.Resour
 }
 
 func resourceComputeInstanceTemplateScratchDiskCustomizeDiff(diff *schema.ResourceDiff, meta interface{}) error {
+	// separate func to allow unit testing
+	return resourceComputeInstanceTemplateScratchDiskCustomizeDiffFunc(diff)
+}
+
+func resourceComputeInstanceTemplateScratchDiskCustomizeDiffFunc(diff TerraformResourceDiff) error {
 	numDisks := diff.Get("disk.#").(int)
 	for i := 0; i < numDisks; i++ {
 		// misspelled on purpose, type is a special symbol
@@ -534,6 +539,11 @@ func resourceComputeInstanceTemplateScratchDiskCustomizeDiff(diff *schema.Resour
 		if diskType == "local-ssd" && typee != "SCRATCH" {
 			return fmt.Errorf("disks with a disk_type of local-ssd must be SCRATCH disks. disk %d is a %s disk", i, typee)
 		}
+
+		diskSize := diff.Get(fmt.Sprintf("disk.%d.disk_size_gb", i)).(int)
+		if typee == "SCRATCH" && diskSize != 375 {
+			return fmt.Errorf("SCRATCH disks must be exactly 375GB, disk %d is %d", i, diskSize)
+		}
 	}
 
 	return nil

diff --git a/third_party/terraform/tests/resource_compute_instance_template_test.go b/third_party/terraform/tests/resource_compute_instance_template_test.go
@@ -161,6 +161,54 @@ func TestComputeInstanceTemplate_reorderDisks(t *testing.T) {
 	}
 }
 
+func TestComputeInstanceTemplate_scratchDiskSizeCustomizeDiff(t *testing.T) {
+	t.Parallel()
+
+	cases := map[string]struct {
+		Typee       string // misspelled on purpose, type is a special symbol
+		DiskType    string
+		DiskSize    int
+		ExpectError bool
+	}{
+		"scratch disk correct size": {
+			Typee:       "SCRATCH",
+			DiskType:    "local-ssd",
+			DiskSize:    375,
+			ExpectError: false,
+		},
+		"scratch disk incorrect size": {
+			Typee:       "SCRATCH",
+			DiskType:    "local-ssd",
+			DiskSize:    300,
+			ExpectError: true,
+		},
+		"non-scratch disk": {
+			Typee:       "PERSISTENT",
+			DiskType:    "",
+			DiskSize:    300,
+			ExpectError: false,
+		},
+	}
+
+	for tn, tc := range cases {
+		d := &ResourceDiffMock{
+			After: map[string]interface{}{
+				"disk.#":              1,
+				"disk.0.type":         tc.Typee,
+				"disk.0.disk_type":    tc.DiskType,
+				"disk.0.disk_size_gb": tc.DiskSize,
+			},
+		}
+		err := resourceComputeInstanceTemplateScratchDiskCustomizeDiffFunc(d)
+		if tc.ExpectError && err == nil {
+			t.Errorf("%s failed, expected error but was none", tn)
+		}
+		if !tc.ExpectError && err != nil {
+			t.Errorf("%s failed, found unexpected error: %s", tn, err)
+		}
+	}
+}
+
 func TestAccComputeInstanceTemplate_basic(t *testing.T) {
 	t.Parallel()
 

diff --git a/third_party/terraform/utils/test_utils.go b/third_party/terraform/utils/test_utils.go
@@ -72,6 +72,10 @@ func (d *ResourceDiffMock) GetChange(key string) (interface{}, interface{}) {
 	return d.Before[key], d.After[key]
 }
 
+func (d *ResourceDiffMock) Get(key string) interface{} {
+	return d.After[key]
+}
+
 func (d *ResourceDiffMock) Clear(key string) error {
 	if d.Cleared == nil {
 		d.Cleared = map[string]struct{}{}

diff --git a/third_party/terraform/utils/utils.go.erb b/third_party/terraform/utils/utils.go.erb
@@ -30,6 +30,7 @@ type TerraformResourceData interface {
 
 type TerraformResourceDiff interface {
 	GetChange(string) (interface{}, interface{})
+	Get(string) interface{}
 	Clear(string) error
 }