Allow using specific zones when creating a VPC. (#638)

CHANGELOG.md

@@ -2,7 +2,7 @@ CHANGELOG
 =========
 
 ## HEAD (Unreleased)
-
+* Introduce `requestedAvailabilityZone` on `ec2.vps.VpcArgs` that takes `number | "all" | string[]`, to allow specific zones for creating a VPC.
 * Extend the `volumeSize` of the default root block device in ECS
   autoscaling launch configuration to 32 GB to accomodate the latest
   default AMI snapshot size

nodejs/awsx/ec2/README.md

@@ -33,21 +33,21 @@ const vpc = new awsx.ec2.Vpc("custom", {
 });
 ```
 
-This range will then be partitioned accordingly into the VPC depending on the other arguments provided.  The additional arguments that affect this partitioning are `subnets` and `numberOfAvailabilityZones`.
+This range will then be partitioned accordingly into the VPC depending on the other arguments provided.  The additional arguments that affect this partitioning are `subnets` and `requestedAvailabilityZones`.
 
 ### Availability Zones
 
 Availability Zones are distinct locations that are engineered to be isolated from failures in other Availability Zones. By launching instances in separate Availability Zones, you can protect your applications from the failure of a single location
 
-If not provided `numberOfAvailabilityZones` will default to `2`, but a different value can be specified like so if appropriate for your region:
+Not providing a list of zones for `requestedAvailabilityZones` will default to `2`, but a different value can be specified like so if appropriate for your region:
 
 ```ts
 import * as aws from "@pulumi/aws";
 import * as awsx from "@pulumi/awsx";
 
 const vpc = new awsx.ec2.Vpc("custom", {
    cidrBlock: "10.0.0.0/16",
-   numberOfAvailabilityZones: 3,
+   requestedAvailabilityZones: 3,
 });
 ```
 
@@ -77,7 +77,7 @@ import * as awsx from "@pulumi/awsx";
 
 const vpc = new awsx.ec2.Vpc("custom", {
    cidrBlock: "10.0.0.0/16",
-   numberOfAvailabilityZones: 3,
+   requestedAvailabilityZones: 3,
    subnets: [{ type: "public" }, { type: "private" }, { type: isolated }],
 });
 ```
@@ -90,7 +90,7 @@ import * as awsx from "@pulumi/awsx";
 
 const vpc = new awsx.ec2.Vpc("custom", {
    cidrBlock: "10.0.0.0/16",
-   numberOfAvailabilityZones: 3,
+   requestedAvailabilityZones: 3,
    subnets: [
      { type: "public" },
      { type: "private" },
@@ -113,7 +113,7 @@ import * as awsx from "@pulumi/awsx";
 
 const vpc = new awsx.ec2.Vpc("custom", {
    cidrBlock: "10.0.0.0/16",
-   numberOfAvailabilityZones: 3,
+   requestedAvailabilityZones: 3,
    numberOfNatGateways: 1,
 });
 ```

nodejs/awsx/ec2/vpc.ts

@@ -327,7 +327,7 @@ export class Vpc extends pulumi.ComponentResource<VpcData> {
     /** @internal */
     public async initializeVpcArgs(name: string, args: x.ec2.VpcArgs, opts: pulumi.ComponentResourceOptions): Promise<VpcData> {
         const provider = Vpc.getProvider(opts);
-        const availabilityZones = await getAvailabilityZones(opts.parent, provider, args.numberOfAvailabilityZones);
+        const availabilityZones = await getAvailabilityZones(opts.parent, provider, args.requestedAvailabilityZones ?? args.numberOfAvailabilityZones);
 
         return new VpcData(name, this, {
             ...args,
@@ -504,23 +504,30 @@ utils.Capture(Vpc.prototype).initializeVpcArgs.doNotCapture = true;
 async function getAvailabilityZones(
         parent: pulumi.Resource | undefined,
         provider: pulumi.ProviderResource | undefined,
-        requestedCount: "all" | number | undefined): Promise<topology.AvailabilityZoneDescription[]> {
+        requestedZones: VpcArgs["requestedAvailabilityZones"] = 2): Promise<topology.AvailabilityZoneDescription[]> {
 
     const result = await aws.getAvailabilityZones(/*args:*/ undefined, { provider, async: true });
     if (result.names.length !== result.zoneIds.length) {
         throw new pulumi.ResourceError("Availability zones for region had mismatched names and ids.", parent);
     }
 
-    const descriptions: topology.AvailabilityZoneDescription[] = [];
-    for (let i = 0, n = result.names.length; i < n; i++) {
-        descriptions.push({ name: result.names[i], id: result.zoneIds[i] });
-    }
 
-    const count =
-        typeof requestedCount === "number" ? requestedCount :
-        requestedCount === "all" ? descriptions.length : 2;
+    const descriptions = result.names.map((name, idx) => ({ name, id: result.zoneIds[idx] }) );
+
+    if (Array.isArray(requestedZones) || typeof requestedZones === "object" ) {
+        return new Promise((resolve, reject) => {
+            pulumi.Output.create(requestedZones).apply(requestedZones => {
+                const mappedZones = descriptions.filter(zone => requestedZones.includes(zone.name));
+                mappedZones.length === requestedZones.length ?
+                    resolve(mappedZones) :
+                    reject(new pulumi.ResourceError("Availability zones did not match requested zones", parent));
+            });
+        });
+    }
+    else {
+        return descriptions.slice(0, requestedZones === "all" ? descriptions.length : requestedZones);
+    }
 
-    return descriptions.slice(0, count);
 }
 
 function getExistingSubnets(vpcData: VpcData, vpc: Vpc, vpcName: string, type: VpcSubnetType, inputs: pulumi.Input<string>[] = []) {
@@ -702,10 +709,12 @@ export interface VpcArgs {
     subnets?: VpcSubnetArgs[];
 
     /**
-     * The maximum number of availability zones to use in the current region.  Defaults to `2` if
-     * unspecified.  Use `"all"` to use all the availability zones in the current region.
+     * The names of the availability zones to use in the current region. Defaults to `2` if
+     * unspecified. Use `"all"` to use all the availability zones in the current region.
      */
-    numberOfAvailabilityZones?: number | "all";
+    requestedAvailabilityZones?: number | "all" | [string, ...string[]] | pulumi.Input<string[]>;
+
+    numberOfAvailabilityZones?: VpcArgs["requestedAvailabilityZones"];
 
     /**
      * The max number of NAT gateways to create if there are any private subnets created.  A NAT

nodejs/examples/vpc/index.ts

@@ -15,6 +15,7 @@
 import * as pulumi from "@pulumi/pulumi";
 import * as aws from "@pulumi/aws";
 import * as awsx from "@pulumi/awsx";
+import * as random from "@pulumi/random";
 
 const config = new pulumi.Config("aws");
 const providerOpts = { provider: new aws.Provider("prov", { region: <aws.Region>config.require("envRegion") }) };
@@ -53,4 +54,22 @@ const vpcWithLocations = new awsx.ec2.Vpc("custom6", {
         { type: "isolated", name: "db", location: "10.0.2.0/24" },
         { type: "isolated", name: "redis", location: "10.0.3.0/24" },
     ],
-}, providerOpts);
+}, providerOpts);
+
+
+
+const allZones =   aws.getAvailabilityZones(undefined, { provider: providerOpts.provider, async: true }).then(allZones => allZones.names)
+const selectedZones = new random.RandomShuffle("custom7_az", {
+    inputs: allZones,
+    resultCount: allZones.then(z => z.length / 2)
+}).results;
+
+const vpcWithSpecificZones = new awsx.ec2.Vpc("custom7", {
+    requestedAvailabilityZones: selectedZones,
+    subnets: [
+        { type: "public" },
+        { type: "private" },
+        { type: "isolated", name: "db" },
+        { type: "isolated", name: "redis" },
+    ],
+}, providerOpts);

nodejs/examples/vpc/package.json

@@ -9,7 +9,8 @@
     },
     "dependencies": {
         "@pulumi/pulumi": "^3.0.0",
-        "@pulumi/aws": "^4.0.0"
+        "@pulumi/aws": "^4.0.0",
+        "@pulumi/random": "^4.0.0"
     },
     "devDependencies": {
         "@types/node": "^8.0.0"