feat: Add option to specify zone in compute_instance (#162)

* Add option to specify zone in compute_instance

Also added a test that creates two instances and ensure they're in the same specified zone.

* Update docs

* Update examples/compute_instance/simple/variables.tf

Co-authored-by: Bharath KKB <[email protected]>

* Update modules/compute_instance/variables.tf

Co-authored-by: Bharath KKB <[email protected]>

* Remove newlines

* Update docs

Co-authored-by: Bharath KKB <[email protected]>

.kitchen.yml

@@ -50,6 +50,11 @@ suites:
       name: terraform
       command_timeout: 1800
       root_module_directory: test/fixtures/compute_instance/simple
+  - name: instance_simple_zone
+    driver:
+      name: terraform
+      command_timeout: 1800
+      root_module_directory: test/fixtures/compute_instance/simple_zone
   - name: disk_snapshot
     driver:
       name: terraform

examples/compute_instance/simple/README.md

@@ -14,6 +14,7 @@ This is a simple, minimal example of how to use the compute_instance module
 | region | The GCP region to create and test resources in | `string` | `"us-central1"` | no |
 | service\_account | Service account to attach to the instance. See https://www.terraform.io/docs/providers/google/r/compute_instance_template.html#service_account. | <pre>object({<br>    email  = string,<br>    scopes = set(string)<br>  })</pre> | `null` | no |
 | subnetwork | The subnetwork selflink to host the compute instances in | `any` | n/a | yes |
+| zone | The GCP zone to create resources in | `string` | `null` | no |
 
 ## Outputs
 

examples/compute_instance/simple/main.tf

@@ -30,6 +30,7 @@ module "instance_template" {
 module "compute_instance" {
   source            = "../../../modules/compute_instance"
   region            = var.region
+  zone              = var.zone
   subnetwork        = var.subnetwork
   num_instances     = var.num_instances
   hostname          = "instance-simple"

examples/compute_instance/simple/variables.tf

@@ -27,6 +27,12 @@ variable "region" {
   default     = "us-central1"
 }
 
+variable "zone" {
+  description = "The GCP zone to create resources in"
+  type        = string
+  default     = null
+}
+
 variable "subnetwork" {
   description = "The subnetwork selflink to host the compute instances in"
 }

modules/compute_instance/README.md

@@ -24,6 +24,7 @@ See the [simple](https://github.com/terraform-google-modules/terraform-google-vm
 | static\_ips | List of static IPs for VM instances | `list(string)` | `[]` | no |
 | subnetwork | Subnet to deploy to. Only one of network or subnetwork should be specified. | `string` | `""` | no |
 | subnetwork\_project | The project that subnetwork belongs to | `string` | `""` | no |
+| zone | Zone where the instances should be created. If not specified, instances will be spread across available zones in the region. | `string` | `null` | no |
 
 ## Outputs
 

modules/compute_instance/main.tf

@@ -43,7 +43,7 @@ resource "google_compute_instance_from_template" "compute_instance" {
   count    = local.num_instances
   name     = "${local.hostname}-${format("%03d", count.index + 1)}"
   project  = local.project_id
-  zone     = data.google_compute_zones.available.names[count.index % length(data.google_compute_zones.available.names)]
+  zone     = var.zone == null ? data.google_compute_zones.available.names[count.index % length(data.google_compute_zones.available.names)] : var.zone
 
   network_interface {
     network            = var.network

modules/compute_instance/variables.tf

@@ -64,3 +64,8 @@ variable "region" {
   default     = null
 }
 
+variable "zone" {
+  type        = string
+  description = "Zone where the instances should be created. If not specified, instances will be spread across available zones in the region."
+  default     = null
+}

test/fixtures/compute_instance/simple_zone/main.tf

@@ -0,0 +1,26 @@
+/**
+ * Copyright 2018 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+module "instance_simple" {
+  source          = "../../../../examples/compute_instance/simple"
+  project_id      = var.project_id
+  region          = "us-central1"
+  zone            = "us-central1-b"
+  subnetwork      = google_compute_subnetwork.main.self_link
+  num_instances   = 2
+  service_account = var.service_account
+}

test/fixtures/compute_instance/simple_zone/network.tf

@@ -0,0 +1 @@
+../../shared/network.tf

test/fixtures/compute_instance/simple_zone/outputs.tf

@@ -0,0 +1,26 @@
+/**
+ * Copyright 2018 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+output "instances_self_links" {
+  description = "List of instance self-links"
+  value       = module.instance_simple.instances_self_links
+}
+
+output "project_id" {
+  description = "The GCP project to use for integration tests"
+  value       = var.project_id
+}
+

test/fixtures/compute_instance/simple_zone/variables.tf

@@ -0,0 +1,29 @@
+/**
+ * Copyright 2018 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+variable "project_id" {
+  description = "The GCP project to use for integration tests"
+}
+
+variable "service_account" {
+  default = null
+  type = object({
+    email  = string
+    scopes = list(string)
+  })
+  description = "Service account to attach to the instance. See https://www.terraform.io/docs/providers/google/r/compute_instance_template.html#service_account."
+}
+

test/fixtures/compute_instance/simple_zone/versions.tf

@@ -0,0 +1,19 @@
+/**
+ * Copyright 2018 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+terraform {
+  required_version = ">=0.12.6"
+}

test/integration/instance_simple_zone/controls/instance_simple_zone.rb

@@ -0,0 +1,60 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+project_id = attribute('project_id')
+
+expected_instances = 2
+
+control "Compute Instances" do
+  title "Simple Configuration With Zone Specified"
+
+  describe command("gcloud --project=#{project_id} compute instances list --format=json --filter='name~instance-simple*'") do
+    its(:exit_status) { should eq 0 }
+    its(:stderr) { should eq '' }
+
+    let!(:data) do
+      if subject.exit_status == 0
+        JSON.parse(subject.stdout)
+      else
+        []
+      end
+    end
+
+    describe "number of instances" do
+      it "should be #{expected_instances}" do
+        expect(data.length).to eq(expected_instances)
+      end
+    end
+
+    describe "instance 001" do
+      let(:instance) do
+        data.find { |i| i['name'] == "instance-simple-001" }
+      end
+
+      it "should be in zone us-central1-b}" do
+        expect(instance['zone']).to match(/.*us-central1-b$/)
+      end
+    end
+
+    describe "instance 002" do
+      let(:instance) do
+        data.find { |i| i['name'] == "instance-simple-002" }
+      end
+
+      it "should be in zone us-central1-b}" do
+        expect(instance['zone']).to match(/.*us-central1-b$/)
+      end
+    end
+  end
+end

test/integration/instance_simple_zone/inspec.yml

@@ -0,0 +1,20 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+---
+name: instance_simple_zone
+attributes:
+  - name: project_id
+    required: true
+    type: string