feat(aws-eks): add atomic flag for HelmChart construct

packages/@aws-cdk/aws-eks/lib/helm-chart.ts

@@ -73,6 +73,13 @@ export interface HelmChartOptions {
    */
   readonly timeout?: Duration;
 
+  /**
+   * Whether or not Helm should treat this operation as atomic; if set, upgrade process rolls back changes
+   * made in case of failed upgrade. The --wait flag will be set automatically if --atomic is used.
+   * @default false
+   */
+  readonly atomic?: boolean;
+
   /**
    * create namespace if not exist
    * @default true
@@ -129,6 +136,8 @@ export class HelmChart extends Construct {
     const wait = props.wait ?? false;
     // default to create new namespace
     const createNamespace = props.createNamespace ?? true;
+    // default to not use atomic operations
+    const atomic = props.atomic ?? false;
 
     props.chartAsset?.grantRead(provider.handlerRole);
 
@@ -143,6 +152,7 @@ export class HelmChart extends Construct {
         ChartAssetURL: props.chartAsset?.s3ObjectUrl,
         Version: props.version,
         Wait: wait || undefined, // props are stringified so we encode “false” as undefined
+        Atomic: atomic || undefined, // props are stringified so we encode “false” as undefined
         Timeout: timeout ? `${timeout.toString()}s` : undefined, // Helm v3 expects duration instead of integer
         Values: (props.values ? stack.toJsonString(props.values) : undefined),
         Namespace: props.namespace ?? 'default',

packages/@aws-cdk/aws-eks/lib/kubectl-handler/helm/__init__.py

@@ -42,6 +42,7 @@ def helm_handler(event, context):
     chart_asset_url  = props.get('ChartAssetURL', None)
     version          = props.get('Version', None)
     wait             = props.get('Wait', False)
+    atomic           = props.get('Atomic', False)
     timeout          = props.get('Timeout', None)
     namespace        = props.get('Namespace', None)
     create_namespace = props.get('CreateNamespace', None)
@@ -146,7 +147,7 @@ def get_chart_from_oci(tmpdir, release, repository = None, version = None):
     raise Exception(f'Operation failed after {maxAttempts} attempts: {output}')
 
 
-def helm(verb, release, chart = None, repo = None, file = None, namespace = None, version = None, wait = False, timeout = None, create_namespace = None):
+def helm(verb, release, chart = None, repo = None, file = None, namespace = None, version = None, wait = False, atomic = False, timeout = None, create_namespace = None):
     import subprocess
 
     cmnd = ['helm', verb, release]
@@ -166,6 +167,8 @@ def helm(verb, release, chart = None, repo = None, file = None, namespace = None
         cmnd.extend(['--namespace', namespace])
     if wait:
         cmnd.append('--wait')
+    if atomic:
+        cmnd.append("--atomic")
     if not timeout is None:
         cmnd.extend(['--timeout', timeout])
     cmnd.extend(['--kubeconfig', kubeconfig])

packages/@aws-cdk/aws-eks/test/helm-chart.test.ts

@@ -187,6 +187,29 @@ describe('helm chart', () => {
       // THEN
       Template.fromStack(stack).hasResourceProperties(eks.HelmChart.RESOURCE_TYPE, { Wait: true });
     });
+
+    test('should disable atomic operations by default', () => {
+      // GIVEN
+      const { stack, cluster } = testFixtureCluster();
+
+      // WHEN
+      new eks.HelmChart(stack, 'MyChart', { cluster, chart: 'chart' });
+
+      // THEN
+      const charts = Template.fromStack(stack).findResources(eks.HelmChart.RESOURCE_TYPE, { Atomic: true });
+      expect(Object.keys(charts).length).toEqual(0);
+    });
+    test('should enable atomic operations when specified', () => {
+      // GIVEN
+      const { stack, cluster } = testFixtureCluster();
+
+      // WHEN
+      new eks.HelmChart(stack, 'MyAtomicChart', { cluster, chart: 'chart', atomic: true });
+
+      // THEN
+      Template.fromStack(stack).hasResourceProperties(eks.HelmChart.RESOURCE_TYPE, { Atomic: true });
+    });
+
     test('should disable waiting when specified as false', () => {
       // GIVEN
       const { stack, cluster } = testFixtureCluster();