fix: Don't collect runtime information when versionReporting is disabled

packages/@aws-cdk/cdk/lib/app.ts

@@ -45,10 +45,14 @@ export class App extends Root {
 
     const result: cxapi.SynthesizeResponse = {
       version: cxapi.PROTO_RESPONSE_VERSION,
-      stacks: this.synthesizeStacks(Object.keys(this.stacks)),
-      runtime: this.collectRuntimeInformation()
+      stacks: this.synthesizeStacks(Object.keys(this.stacks))
     };
 
+    const disableVersionReporting = this.node.getContext(cxapi.DISABLE_VERSION_REPORTING);
+    if (!disableVersionReporting) {
+      result.runtime = this.collectRuntimeInformation();
+    }
+
     const outfile = path.join(outdir, cxapi.OUTFILE_NAME);
     fs.writeFileSync(outfile, JSON.stringify(result, undefined, 2));
   }

packages/@aws-cdk/cdk/test/test.app.ts

@@ -268,6 +268,19 @@ export = {
     test.done();
   },
 
+  'runtime library versions disabled'(test: Test) {
+    const context: any = {};
+    context[cxapi.DISABLE_VERSION_REPORTING] = true;
+
+    const response = withApp(context, app => {
+      const stack = new Stack(app, 'stack1');
+      new Resource(stack, 'MyResource', { type: 'Resource::Type' });
+    });
+
+    test.equals(response.runtime, undefined);
+    test.done();
+  },
+
   'runtime library versions'(test: Test) {
     const response = withApp({}, app => {
       const stack = new Stack(app, 'stack1');

packages/@aws-cdk/cx-api/lib/cxapi.ts

@@ -133,3 +133,8 @@ export const PATH_METADATA_KEY = 'aws:cdk:path';
  * Enables the embedding of the "aws:cdk:path" in CloudFormation template metadata.
  */
 export const PATH_METADATA_ENABLE_CONTEXT = 'aws:cdk:enable-path-metadata';
+
+/**
+ * Disable the collection and reporting of version information.
+ */
+export const DISABLE_VERSION_REPORTING = 'aws:cdk:disable-version-reporting';

packages/aws-cdk/lib/api/cxapp/exec.ts

@@ -33,6 +33,15 @@ export async function execProgram(aws: SDK, config: Settings): Promise<cxapi.Syn
     context[cxapi.ASSET_RESOURCE_METADATA_ENABLED_CONTEXT] = true;
   }
 
+  let versionReporting: boolean = config.get(['versionReporting']);
+  if (versionReporting === undefined) {
+    versionReporting = true; // defaults to true
+  }
+
+  if (!versionReporting) {
+    context[cxapi.DISABLE_VERSION_REPORTING] = true;
+  }
+
   debug('context:', context);
 
   env[cxapi.CONTEXT_ENV] = JSON.stringify(context);