Add support for setting kube version on data.helm_template. (#985)

* Add support for setting kube version on data.template.

* Add test for unparsable kube-version.

* Add kube_version to docs.

* Change doc of kube_version to be more in line with description from helm package.

helm/data_template.go

@@ -346,6 +346,11 @@ func dataTemplate() *schema.Resource {
 				Computed:    true,
 				Description: "Rendered notes if the chart contains a `NOTES.txt`.",
 			},
+			"kube_version": {
+				Type:        schema.TypeString,
+				Optional:    true,
+				Description: "Kubernetes version used for Capabilities.KubeVersion",
+			},
 		},
 	}
 }
@@ -449,6 +454,14 @@ func dataTemplateRead(ctx context.Context, d *schema.ResourceData, meta interfac
 	client.Description = d.Get("description").(string)
 	client.CreateNamespace = d.Get("create_namespace").(bool)
 
+	if ver := d.Get("kube_version").(string); ver != "" {
+		parsedVer, err := chartutil.ParseKubeVersion(ver)
+		if err != nil {
+			return diag.FromErr(fmt.Errorf("couldn't parse string %q into kube-version", ver))
+		}
+		client.KubeVersion = parsedVer
+	}
+
 	// The following source has been adapted from the source of the helm template command
 	// https://github.com/helm/helm/blob/v3.5.3/cmd/helm/template.go#L67
 	client.DryRun = true

helm/data_template_test.go

@@ -2,6 +2,7 @@ package helm
 
 import (
 	"fmt"
+	"regexp"
 	"testing"
 
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
@@ -82,6 +83,57 @@ data:
 	})
 }
 
+func TestAccDataTemplate_kubeVersion(t *testing.T) {
+	name := randName("kube-version")
+	namespace := randName(testNamespacePrefix)
+
+	datasourceAddress := fmt.Sprintf("data.helm_template.%s", testResourceName)
+
+	// No kube version set, will fail as v1.20.0.
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{{
+			Config:      testAccDataHelmTemplateKubeVersionNoVersionSet(testResourceName, namespace, name, "1.2.3"),
+			ExpectError: regexp.MustCompile("chart requires kubeVersion.*"),
+		}},
+	})
+
+	// Kube Version set but for a to low version.
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{{
+			Config:      testAccDataHelmTemplateKubeVersion(testResourceName, namespace, name, "1.2.3", "1.18.0"),
+			ExpectError: regexp.MustCompile("chart requires kubeVersion.*"),
+		}},
+	})
+
+	// Kube Version set but not parsable.
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{{
+			Config:      testAccDataHelmTemplateKubeVersion(testResourceName, namespace, name, "1.2.3", "abcdef"),
+			ExpectError: regexp.MustCompile(`couldn't parse string "abcdef" into kube-version`),
+		}},
+	})
+
+	// Kube Version set and above the min version.
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{{
+			Config: testAccDataHelmTemplateKubeVersion(testResourceName, namespace, name, "1.2.3", "1.22.0"),
+			Check: resource.ComposeAggregateTestCheckFunc(
+				resource.TestCheckResourceAttr(datasourceAddress, "manifests.%", "1"),
+				resource.TestCheckResourceAttrSet(datasourceAddress, "manifests.templates/deployment.yaml"),
+				resource.TestCheckResourceAttrSet(datasourceAddress, "manifest"),
+			),
+		}},
+	})
+}
+
 func testAccDataHelmTemplateConfigBasic(resource, ns, name, version string) string {
 	return fmt.Sprintf(`
 		data "helm_template" "%s" {
@@ -133,3 +185,30 @@ func testAccDataHelmTemplateConfigTemplates(resource, ns, name, version string)
 		}
 	`, resource, name, ns, testRepositoryURL, version)
 }
+
+func testAccDataHelmTemplateKubeVersion(resource, ns, name, version, kubeVersion string) string {
+	return fmt.Sprintf(`
+		data "helm_template" "%s" {
+ 			name         = %q
+			namespace    = %q
+			description  = "Test"
+			repository   = %q
+  			chart        = "kube-version"
+			version      = %q
+			kube_version = %q
+		}
+	`, resource, name, ns, testRepositoryURL, version, kubeVersion)
+}
+
+func testAccDataHelmTemplateKubeVersionNoVersionSet(resource, ns, name, version string) string {
+	return fmt.Sprintf(`
+		data "helm_template" "%s" {
+ 			name         = %q
+			namespace    = %q
+			description  = "Test"
+			repository   = %q
+  			chart        = "kube-version"
+			version      = %q
+		}
+	`, resource, name, ns, testRepositoryURL, version)
+}

helm/testdata/charts/kube-version/Chart.yaml

@@ -0,0 +1,7 @@
+apiVersion: v2
+name: kube-version
+description: A chart requiring kube version 1.22 or above
+type: application
+version: 1.2.3
+appVersion: 1.2.3
+kubeVersion: ">=1.22.0-0"

helm/testdata/charts/kube-version/templates/_helpers.tpl

@@ -0,0 +1,42 @@
+{{/*
+Expand the name of the chart.
+*/}}
+{{- define "kube-version.name" -}}
+{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Create a default fully qualified app name.
+We truncate at 63 chars because some Kubernetes name fields are limited to this (by the DNS naming spec).
+If release name contains chart name it will be used as a full name.
+*/}}
+{{- define "kube-version.fullname" -}}
+{{- if .Values.fullnameOverride }}
+{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- $name := default .Chart.Name .Values.nameOverride }}
+{{- if contains $name .Release.Name }}
+{{- .Release.Name | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
+{{- end }}
+{{- end }}
+{{- end }}
+
+{{/*
+Create chart name and version as used by the chart label.
+*/}}
+{{- define "kube-version.chart" -}}
+{{- printf "%s-%s" .Chart.Name .Chart.Version | replace "+" "_" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+
+{{/*
+Common labels
+*/}}
+{{- define "kube-version.labels" -}}
+helm.sh/chart: {{ include "kube-version.chart" . }}
+{{- if .Chart.AppVersion }}
+app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
+{{- end }}
+app.kubernetes.io/managed-by: {{ .Release.Service }}
+{{- end }}

helm/testdata/charts/kube-version/templates/deployment.yaml

@@ -0,0 +1,53 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "kube-version.fullname" . }}
+  labels:
+    {{- include "kube-version.labels" . | nindent 4 }}
+spec:
+  replicas: {{ .Values.replicaCount }}
+  template:
+    metadata:
+    {{- with .Values.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+    {{- end }}
+    spec:
+      {{- with .Values.imagePullSecrets }}
+      imagePullSecrets:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      securityContext:
+        {{- toYaml .Values.podSecurityContext | nindent 8 }}
+      containers:
+        - name: {{ .Chart.Name }}
+          securityContext:
+            {{- toYaml .Values.securityContext | nindent 12 }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          ports:
+            - name: http
+              containerPort: 80
+              protocol: TCP
+          livenessProbe:
+            httpGet:
+              path: /
+              port: http
+          readinessProbe:
+            httpGet:
+              path: /
+              port: http
+          resources:
+            {{- toYaml .Values.resources | nindent 12 }}
+      {{- with .Values.nodeSelector }}
+      nodeSelector:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}

helm/testdata/charts/kube-version/values.yaml

@@ -0,0 +1,49 @@
+# Default values for kube-version.
+# This is a YAML-formatted file.
+# Declare variables to be passed into your templates.
+
+replicaCount: 1
+
+image:
+  repository: nginx
+  pullPolicy: IfNotPresent
+  # Overrides the image tag whose default is the chart appVersion.
+  tag: ""
+
+imagePullSecrets: []
+nameOverride: ""
+fullnameOverride: ""
+
+podAnnotations: {}
+
+podSecurityContext:
+  {}
+  # fsGroup: 2000
+
+securityContext:
+  {}
+  # capabilities:
+  #   drop:
+  #   - ALL
+  # readOnlyRootFilesystem: true
+  # runAsNonRoot: true
+  # runAsUser: 1000
+
+resources:
+  {}
+  # We usually recommend not to specify default resources and to leave this as a conscious
+  # choice for the user. This also increases chances charts run on environments with little
+  # resources, such as Minikube. If you do want to specify resources, uncomment the following
+  # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
+  # limits:
+  #   cpu: 100m
+  #   memory: 128Mi
+  # requests:
+  #   cpu: 100m
+  #   memory: 128Mi
+
+nodeSelector: {}
+
+tolerations: []
+
+affinity: {}

website/docs/d/template.html.markdown

@@ -155,6 +155,7 @@ The following attributes are specific to the `helm_template` data source and not
 * `is_upgrade` - (Optional) Set .Release.IsUpgrade instead of .Release.IsInstall. Defaults to `false`.
 * `show_only` - (Optional) Explicit list of chart templates to render, as Helm does with the `-s` or `--show-only` option. Paths to chart templates are relative to the root folder of the chart, e.g. `templates/deployment.yaml`. If not provided, all templates of the chart are rendered.
 * `validate` - (Optional) Validate your manifests against the Kubernetes cluster you are currently pointing at. This is the same validation performed on an install. Defaults to `false`.
+* `kube_version` - (Optional) Allows specifying a custom kubernetes version to use when templating.
 
 ## Attributes Reference