From 744d7dab69d79e8b12b7c80039530a04e8a90de3 Mon Sep 17 00:00:00 2001
From: Joe Flateau <joe@joeflateau.net>
Date: Tue, 31 May 2022 22:20:47 -0400
Subject: [PATCH] ensure docker build platform is passed along to
 DefaultStackSynthesizer

---
 .../aws-ecr-assets/test/image-asset.test.ts      | 16 ++++++++++++++++
 .../_asset-manifest-builder.ts                   |  1 +
 2 files changed, 17 insertions(+)

diff --git a/packages/@aws-cdk/aws-ecr-assets/test/image-asset.test.ts b/packages/@aws-cdk/aws-ecr-assets/test/image-asset.test.ts
index 4fe6299ab9c87..89a5aeb3d0309 100644
--- a/packages/@aws-cdk/aws-ecr-assets/test/image-asset.test.ts
+++ b/packages/@aws-cdk/aws-ecr-assets/test/image-asset.test.ts
@@ -170,6 +170,22 @@ describe('image asset', () => {
     expect(assetMetadata && (assetMetadata.data as cxschema.ContainerImageAssetMetadataEntry).platform).toEqual('linux/arm64');
   });
 
+  testFutureBehavior('with platform: default synth edition', flags, App, (app) => {
+    // GIVEN
+    const stack = new Stack(app, 'Stack', { synthesizer: new DefaultStackSynthesizer() });
+    // WHEN
+    const asset = new DockerImageAsset(stack, 'Image', {
+      directory: path.join(__dirname, 'demo-image'),
+      platform: Platform.LINUX_ARM64,
+    });
+
+    // THEN
+    const asm = app.synth();
+    const stackAssets = JSON.parse(fs.readFileSync(path.join(asm.directory, 'Stack.assets.json'), { encoding: 'utf-8' }));
+    const dockerImageAsset = stackAssets.dockerImages[asset.assetHash];
+    expect(dockerImageAsset.source.platform).toEqual('linux/arm64');
+  });
+
   testFutureBehavior('asset.repository.grantPull can be used to grant a principal permissions to use the image', flags, App, (app) => {
     // GIVEN
     const stack = new Stack(app);
diff --git a/packages/@aws-cdk/core/lib/stack-synthesizers/_asset-manifest-builder.ts b/packages/@aws-cdk/core/lib/stack-synthesizers/_asset-manifest-builder.ts
index b1e121399cf4a..3d0d833245b8d 100644
--- a/packages/@aws-cdk/core/lib/stack-synthesizers/_asset-manifest-builder.ts
+++ b/packages/@aws-cdk/core/lib/stack-synthesizers/_asset-manifest-builder.ts
@@ -93,6 +93,7 @@ export class AssetManifestBuilder {
         dockerBuildTarget: asset.dockerBuildTarget,
         dockerFile: asset.dockerFile,
         networkMode: asset.networkMode,
+        platform: asset.platform,
       },
       destinations: {
         [this.manifestEnvName(stack)]: {