Add an enum union type for AWS instance types

lib/aws/ec2/instance.ts

@@ -11,7 +11,7 @@ export class Instance
         implements InstanceProperties {
 
     public imageId: string;
-    public instanceType?: string;
+    public instanceType?: InstanceType;
     public securityGroups?: SecurityGroup[];
     public keyName?: string;
 
@@ -31,9 +31,117 @@ export interface InstanceProperties extends cloudformation.TagArgs {
     // Provides the unique ID of the Amazon Machine Image (AMI) that was assigned during registration.
     imageId: string;
     // The instance type, such as t2.micro. The default type is "m3.medium".
-    instanceType?: string;
+    instanceType?: InstanceType;
     // A list that contains the Amazon EC2 security groups to assign to the Amazon EC2 instance.
     securityGroups?: SecurityGroup[];
     // Provides the name of the Amazon EC2 key pair.
     keyName?: string;
 }
+
+// InstanceType is an enum type with all the names of instance types available in EC2.
+export type InstanceType =
+    // GENERAL PURPOSE:
+
+    // T2: Instances are Burstable Performance Instances that provide a baseline level of CPU performance with the
+    // ability to burst above the baseline. The baseline performance and ability to burst are governed by CPU Credits.
+    // Each T2 instance receives CPU Credits continuously at a set rate depending on the instance size.  T2 instances
+    // accrue CPU Credits when they are idle, and use CPU credits when they are active.  T2 instances are a good choice
+    // for workloads that don’t use the full CPU often or consistently, but occasionally need to burst (e.g. web
+    // servers, developer environments and databases). For more information see Burstable Performance Instances.
+    "t2.nano"     |
+    "t2.micro"    |
+    "t2.small"    |
+    "t2.medium"   |
+    "t2.large"    |
+    "t2.xlarge"   |
+    "t2.2xlarge"  |
+
+    // M4: Instances are the latest generation of General Purpose Instances. This family provides a balance of compute,
+    // memory, and network resources, and it is a good choice for many applications.
+    "m4.large"    |
+    "m4.xlarge"   |
+    "m4.2xlarge"  |
+    "m4.4xlarge"  |
+    "m4.10xlarge" |
+    "m4.16xlarge" |
+
+    // M3: This family includes the M3 instance types and provides a balance of compute, memory, and network resources,
+    // and it is a good choice for many applications.
+    "m3.medium"   |
+    "m3.large"    |
+    "m3.xlarge"   |
+    "m3.2xlarge"  |
+
+    // COMPUTE OPTIMIZED:
+
+    // C4: Instances are the latest generation of Compute-optimized instances, featuring the highest performing
+    // processors and the lowest price/compute performance in EC2.
+    "c4.large"    |
+    "c4.xlarge"   |
+    "c4.2xlarge"  |
+    "c4.4xlarge"  |
+    "c4.8xlarge"  |
+
+    // C3: Instances are the previous generation of Compute-optimized instances.
+    "c3.large"    |
+    "c3.xlarge"   |
+    "c3.2xlarge"  |
+    "c3.4xlarge"  |
+    "c3.8xlarge"  |
+
+    // MEMORY OPTIMIZED:
+
+    // X1: Instances are optimized for large-scale, enterprise-class, in-memory applications and have the lowest price
+    // per GiB of RAM among Amazon EC2 instance types.
+    "x1.32xlarge" |
+    "x1.16xlarge" |
+
+    // R4: Instances are optimized for memory-intensive applications and offer better price per GiB of RAM than R3.
+    "r4.large"    |
+    "r4.xlarge"   |
+    "r4.2xlarge"  |
+    "r4.4xlarge"  |
+    "r4.8xlarge"  |
+    "r4.16xlarge" |
+
+    // R3: Instances are optimized for memory-intensive applications and offer lower price per GiB of RAM.
+    "r3.large"    |
+    "r3.xlarge"   |
+    "r3.2xlarge"  |
+    "r3.4xlarge"  |
+    "r3.8xlarge"  |
+
+    // ACCELERATED COMPUTING INSTANCES:
+
+    // P2: Instances are intended for general-purpose GPU compute applications. 
+    "p2.xlarge"   |
+    "p2.8xlarge"  |
+    "p2.16xlarge" |
+
+    // G2: Instances are optimized for graphics-intensive applications.
+    "g2.2xlarge"  |
+    "g2.8xlarge"  |
+
+    // F1: Instances offer customizable hardware acceleration with field programmable gate arrays (FPGAs).
+    "f1.2xlarge"  |
+    "f1.16xlarge" |
+
+    // STORAGE OPTIMIZED:
+
+    // I3: This family includes the High Storage Instances that provide Non-Volatile Memory Express (NVMe) SSD backed
+    // instance storage optimized for low latency, very high random I/O performance, high sequential read throughput and
+    // provide high IOPS at a low cost.
+    "i3.large"    |
+    "i3.xlarge"   |
+    "i3.2xlarge"  |
+    "i3.4xlarge"  |
+    "i3.8xlarge"  |
+    "i3.16xlarge" |
+
+    // D2: Instances feature up to 48 TB of HDD-based local storage, deliver high disk throughput, and offer the lowest
+    // price per disk throughput performance on Amazon EC2.
+    "d2.xlarge"   |
+    "d2.2xlarge"  |
+    "d2.4xlarge"  |
+    "d2.8xlarge"  ;
+