feat: use arm64 instances for arm64 platform builds

src/container-image-build.ts

@@ -2,7 +2,7 @@ import { createHash } from 'crypto';
 import { existsSync, readFileSync } from 'fs';
 import { join } from 'path';
 import { CfnResource, CustomResource, Duration, RemovalPolicy } from 'aws-cdk-lib';
-import { BuildSpec, LinuxBuildImage } from 'aws-cdk-lib/aws-codebuild';
+import { BuildSpec, ComputeType, LinuxArmBuildImage, LinuxBuildImage } from 'aws-cdk-lib/aws-codebuild';
 import { IVpc } from 'aws-cdk-lib/aws-ec2';
 import { IRepository, Repository } from 'aws-cdk-lib/aws-ecr';
 import { DockerImageAssetProps } from 'aws-cdk-lib/aws-ecr-assets';
@@ -64,12 +64,12 @@ export class ContainerImageBuild extends Construct implements IGrantable {
       timeout: Duration.minutes(5),
     });
 
-    // use buildx for cross-platform image build.
-    // because soci-snapshotter currently only supports amd64 environment.
-    // const armImage = LinuxArmBuildImage.fromCodeBuildImageId('aws/codebuild/amazonlinux2-aarch64-standard:3.0');
+    // Use buildx for cross-platform image build
+    const armImage = LinuxArmBuildImage.fromCodeBuildImageId('aws/codebuild/amazonlinux2-aarch64-standard:3.0');
     const x64Image = LinuxBuildImage.fromCodeBuildImageId('aws/codebuild/standard:7.0');
-    // const buildImage = props.platform == Platform.LINUX_ARM64 ? armImage : x64Image;
-    const buildImage = x64Image;
+    // Select the build image based on the target platform
+    const isArm64 = props.platform?.platform === 'linux/arm64';
+    const buildImage = isArm64 ? armImage : x64Image;
 
     let repository = props.repository;
     if (repository === undefined) {
@@ -79,8 +79,9 @@ export class ContainerImageBuild extends Construct implements IGrantable {
 
     const project = new SingletonProject(this, 'Project', {
       uuid: 'e83729fe-b156-4e70-9bec-452b15847a30',
-      projectPurpose: 'ContainerImageBuildAmd64',
+      projectPurpose: isArm64 ? 'ContainerImageBuildArm64' : 'ContainerImageBuildAmd64',
       environment: {
+        computeType: ComputeType.SMALL,
         buildImage: buildImage,
         privileged: true,
       },

src/singleton-project.ts

@@ -46,9 +46,14 @@ export class SingletonProject extends Construct {
     // Things that can be added to the slug later (we have to create a new project per these properties):
     //   * vpc addr
     //   * instance type
+    //   * platform (amd64/arm64)
     // But actually, replacement will not cause any disruption because of its stateless nature.
     let slug = '';
     slug += props.vpc?.node.addr ?? '';
+    // Get platform info from environment.buildImage if available
+    if (props.environment?.buildImage) {
+      slug += props.environment.buildImage.toString().includes('aarch64') ? 'arm64' : 'amd64';
+    }
     return slug;
   }