Allow fuzzy matching GKE versions in the GKE version datasource

google-beta/data_source_google_container_engine_versions.go

@@ -2,6 +2,7 @@ package google
 
 import (
 	"fmt"
+	"strings"
 	"time"
 
 	"github.com/hashicorp/terraform/helper/schema"
@@ -15,6 +16,10 @@ func dataSourceGoogleContainerEngineVersions() *schema.Resource {
 				Type:     schema.TypeString,
 				Optional: true,
 			},
+			"version_prefix": {
+				Type:     schema.TypeString,
+				Optional: true,
+			},
 			"zone": {
 				Type:     schema.TypeString,
 				Optional: true,
@@ -72,16 +77,32 @@ func dataSourceGoogleContainerEngineVersionsRead(d *schema.ResourceData, meta in
 		return fmt.Errorf("Error retrieving available container cluster versions: %s", err.Error())
 	}
 
-	d.Set("valid_master_versions", resp.ValidMasterVersions)
-	d.Set("default_cluster_version", resp.DefaultClusterVersion)
-	d.Set("valid_node_versions", resp.ValidNodeVersions)
-	if len(resp.ValidMasterVersions) > 0 {
-		d.Set("latest_master_version", resp.ValidMasterVersions[0])
+	validMasterVersions := make([]string, 0)
+	for _, v := range resp.ValidMasterVersions {
+		if strings.HasPrefix(v, d.Get("version_prefix").(string)) {
+			validMasterVersions = append(validMasterVersions, v)
+		}
 	}
-	if len(resp.ValidNodeVersions) > 0 {
-		d.Set("latest_node_version", resp.ValidNodeVersions[0])
+
+	validNodeVersions := make([]string, 0)
+	for _, v := range resp.ValidNodeVersions {
+		if strings.HasPrefix(v, d.Get("version_prefix").(string)) {
+			validNodeVersions = append(validNodeVersions, v)
+		}
 	}
 
+	d.Set("valid_master_versions", validMasterVersions)
+	if len(validMasterVersions) > 0 {
+		d.Set("latest_master_version", validMasterVersions[0])
+	}
+
+	d.Set("valid_node_versions", validNodeVersions)
+	if len(validNodeVersions) > 0 {
+		d.Set("latest_node_version", validNodeVersions[0])
+	}
+
+	d.Set("default_cluster_version", resp.DefaultClusterVersion)
+
 	d.SetId(time.Now().UTC().String())
 	return nil
 }

google-beta/data_source_google_container_engine_versions_test.go

@@ -27,6 +27,24 @@ func TestAccContainerEngineVersions_basic(t *testing.T) {
 	})
 }
 
+func TestAccContainerEngineVersions_filtered(t *testing.T) {
+	t.Parallel()
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccCheckGoogleContainerEngineVersions_filtered,
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr("data.google_container_engine_versions.versions", "valid_master_versions.#", "0"),
+					resource.TestCheckResourceAttr("data.google_container_engine_versions.versions", "valid_node_versions.#", "0"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccContainerEngineVersions_regional(t *testing.T) {
 	t.Parallel()
 
@@ -120,6 +138,13 @@ data "google_container_engine_versions" "versions" {
 }
 `
 
+var testAccCheckGoogleContainerEngineVersions_filtered = `
+data "google_container_engine_versions" "versions" {
+  zone           = "us-central1-b"
+  version_prefix = "1.1."
+}
+`
+
 var testAccCheckGoogleContainerEngineVersionsRegionalConfig = `
 data "google_container_engine_versions" "versions" {
   region = "us-central1"

website/docs/d/google_container_engine_versions.html.markdown

@@ -18,7 +18,8 @@ to the datasource. A `region` can have a different set of supported versions tha
 
 ```hcl
 data "google_container_engine_versions" "central1b" {
-  zone = "us-central1-b"
+  zone           = "us-central1-b"
+  version_prefix = "1.12."
 }
 
 resource "google_container_cluster" "foo" {
@@ -48,6 +49,13 @@ The following arguments are supported:
 * `project` (optional) - ID of the project to list available cluster versions for. Should match the project the cluster will be deployed to.
   Defaults to the project that the provider is authenticated with.
 
+* `version_prefix` (optional) - If provided, Terraform will only return versions
+that match the string prefix. For example, `1.11.` will match all `1.11` series
+releases. Since this is just a string match, it's recommended that you append a
+`.` after minor versions to ensure that prefixes such as `1.1` don't match
+versions like `1.12.5-gke.10` accidentally. See [the docs on versioning schema](https://cloud.google.com/kubernetes-engine/versioning-and-upgrades#versioning_scheme)
+for full details on how version strings are formatted.
+
 ## Attributes Reference
 
 The following attributes are exported:

website/docs/r/container_cluster.html.markdown

@@ -213,7 +213,9 @@ output "cluster_ca_certificate" {
     If unset, the cluster's version will be set by GKE to the version of the most recent
     official release (which is not necessarily the latest version).  Most users will find
     the `google_container_engine_versions` data source useful - it indicates which versions
-    are available.  If you intend to specify versions manually, [the docs](https://cloud.google.com/kubernetes-engine/versioning-and-upgrades#specifying_cluster_version)
+    are available, and can be use to approximate fuzzy versions in a
+    Terraform-compatible way. If you intend to specify versions manually,
+    [the docs](https://cloud.google.com/kubernetes-engine/versioning-and-upgrades#specifying_cluster_version)
     describe the various acceptable formats for this field.
 
 -> If you are using the `google_container_engine_versions` datasource with a regional cluster, ensure that you have provided a `region`
@@ -249,8 +251,11 @@ to the datasource. A `region` can have a different set of supported versions tha
 * `node_version` - (Optional) The Kubernetes version on the nodes. Must either be unset
     or set to the same value as `min_master_version` on create. Defaults to the default
     version set by GKE which is not necessarily the latest version. This only affects
-    nodes in the default node pool. To update nodes in other node pools, use the `version`
-    attribute on the node pool.
+    nodes in the default node pool. While a fuzzy version can be specified, it's
+    recommended that you specify explicit versions as Terraform will see spurious diffs
+    when fuzzy versions are used. See the `google_container_engine_versions` data source's
+    `version_prefix` field to approximate fuzzy versions in a Terraform-compatible way.
+    To update nodes in other node pools, use the `version` attribute on the node pool.
 
 * `pod_security_policy_config` - (Optional, [Beta](https://terraform.io/docs/providers/google/provider_versions.html)) Configuration for the
     [PodSecurityPolicy](https://cloud.google.com/kubernetes-engine/docs/how-to/pod-security-policies) feature.

website/docs/r/container_node_pool.html.markdown

@@ -134,7 +134,10 @@ resource "google_container_cluster" "primary" {
 
 * `version` - (Optional) The Kubernetes version for the nodes in this pool. Note that if this field
     and `auto_upgrade` are both specified, they will fight each other for what the node version should
-    be, so setting both is highly discouraged.
+    be, so setting both is highly discouraged. While a fuzzy version can be specified, it's
+    recommended that you specify explicit versions as Terraform will see spurious diffs
+    when fuzzy versions are used. See the `google_container_engine_versions` data source's
+    `version_prefix` field to approximate fuzzy versions in a Terraform-compatible way.
 
 The `autoscaling` block supports: