feat(cli): hotswap deployments for CodeBuild projects (aws#18161)

This extends the `cdk deploy --hotswap` command to support CodeBuild projects. 

This supports all changes to the `Source`, `SourceVersion`, and `Environment` attributes of the AWS::CodeBuild::Project cloudformation resource. The possible changes supported on the [Project](https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_aws-codebuild.Project.html) L2 Construct will be changes to the [buildSpec](https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_aws-codebuild.Project.html#buildspec), [environment](https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_aws-codebuild.Project.html#environment), [environmentVariables](https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_aws-codebuild.Project.html#environmentvariables), and [source](https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_aws-codebuild.Project.html#source) constructor props.

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/aws-cdk/README.md

@@ -366,6 +366,7 @@ Hotswapping is currently supported for the following changes
 - Definition changes of AWS Step Functions State Machines.
 - Container asset changes of AWS ECS Services.
 - Website asset changes of AWS S3 Bucket Deployments.
+- Source and Environment changes of AWS CodeBuild Projects.
 
 **⚠ Note #1**: This command deliberately introduces drift in CloudFormation stacks in order to speed up deployments.
 For this reason, only use it for development purposes.

packages/aws-cdk/lib/api/aws-auth/sdk.ts

@@ -61,6 +61,7 @@ export interface ISDK {
   secretsManager(): AWS.SecretsManager;
   kms(): AWS.KMS;
   stepFunctions(): AWS.StepFunctions;
+  codeBuild(): AWS.CodeBuild
 }
 
 /**
@@ -180,6 +181,10 @@ export class SDK implements ISDK {
     return this.wrapServiceErrorHandling(new AWS.StepFunctions(this.config));
   }
 
+  public codeBuild(): AWS.CodeBuild {
+    return this.wrapServiceErrorHandling(new AWS.CodeBuild(this.config));
+  }
+
   public async currentAccount(): Promise<Account> {
     // Get/refresh if necessary before we can access `accessKeyId`
     await this.forceCredentialRetrieval();

packages/aws-cdk/lib/api/hotswap-deployments.ts

@@ -5,6 +5,7 @@ import * as colors from 'colors/safe';
 import { print } from '../logging';
 import { ISDK, Mode, SdkProvider } from './aws-auth';
 import { DeployStackResult } from './deploy-stack';
+import { isHotswappableCodeBuildProjectChange } from './hotswap/code-build-projects';
 import { ICON, ChangeHotswapImpact, ChangeHotswapResult, HotswapOperation, HotswappableChangeCandidate, ListStackResources } from './hotswap/common';
 import { isHotswappableEcsServiceChange } from './hotswap/ecs-services';
 import { EvaluateCloudFormationTemplate } from './hotswap/evaluate-cloudformation-template';
@@ -77,6 +78,7 @@ async function findAllHotswappableChanges(
         isHotswappableStateMachineChange(logicalId, resourceHotswapEvaluation, evaluateCfnTemplate),
         isHotswappableEcsServiceChange(logicalId, resourceHotswapEvaluation, evaluateCfnTemplate),
         isHotswappableS3BucketDeploymentChange(logicalId, resourceHotswapEvaluation, evaluateCfnTemplate),
+        isHotswappableCodeBuildProjectChange(logicalId, resourceHotswapEvaluation, evaluateCfnTemplate),
       ]);
     }
   });

packages/aws-cdk/lib/api/hotswap/code-build-projects.ts

@@ -0,0 +1,67 @@
+import * as AWS from 'aws-sdk';
+import { ISDK } from '../aws-auth';
+import { ChangeHotswapImpact, ChangeHotswapResult, establishResourcePhysicalName, HotswapOperation, HotswappableChangeCandidate, lowerCaseFirstCharacter, transformObjectKeys } from './common';
+import { EvaluateCloudFormationTemplate } from './evaluate-cloudformation-template';
+
+export async function isHotswappableCodeBuildProjectChange(
+  logicalId: string, change: HotswappableChangeCandidate, evaluateCfnTemplate: EvaluateCloudFormationTemplate,
+): Promise<ChangeHotswapResult> {
+  if (change.newValue.Type !== 'AWS::CodeBuild::Project') {
+    return ChangeHotswapImpact.REQUIRES_FULL_DEPLOYMENT;
+  }
+
+  const updateProjectInput: AWS.CodeBuild.UpdateProjectInput = {
+    name: '',
+  };
+  for (const updatedPropName in change.propertyUpdates) {
+    const updatedProp = change.propertyUpdates[updatedPropName];
+    switch (updatedPropName) {
+      case 'Source':
+        updateProjectInput.source = transformObjectKeys(
+          await evaluateCfnTemplate.evaluateCfnExpression(updatedProp.newValue),
+          convertSourceCloudformationKeyToSdkKey,
+        );
+        break;
+      case 'Environment':
+        updateProjectInput.environment = await transformObjectKeys(
+          await evaluateCfnTemplate.evaluateCfnExpression(updatedProp.newValue),
+          lowerCaseFirstCharacter,
+        );
+        break;
+      case 'SourceVersion':
+        updateProjectInput.sourceVersion = await evaluateCfnTemplate.evaluateCfnExpression(updatedProp.newValue);
+        break;
+      default:
+        return ChangeHotswapImpact.REQUIRES_FULL_DEPLOYMENT;
+    }
+  }
+
+  const projectName = await establishResourcePhysicalName(logicalId, change.newValue.Properties?.Name, evaluateCfnTemplate);
+  if (!projectName) {
+    return ChangeHotswapImpact.REQUIRES_FULL_DEPLOYMENT;
+  }
+  updateProjectInput.name = projectName;
+  return new ProjectHotswapOperation(updateProjectInput);
+}
+
+class ProjectHotswapOperation implements HotswapOperation {
+  public readonly service = 'codebuild'
+  public readonly resourceNames: string[];
+
+  constructor(
+    private readonly updateProjectInput: AWS.CodeBuild.UpdateProjectInput,
+  ) {
+    this.resourceNames = [updateProjectInput.name];
+  }
+
+  public async apply(sdk: ISDK): Promise<any> {
+    return sdk.codeBuild().updateProject(this.updateProjectInput).promise();
+  }
+}
+
+function convertSourceCloudformationKeyToSdkKey(key: string): string {
+  if (key.toLowerCase() === 'buildspec') {
+    return key.toLowerCase();
+  }
+  return lowerCaseFirstCharacter(key);
+}

packages/aws-cdk/lib/api/hotswap/common.ts

@@ -82,3 +82,31 @@ export async function establishResourcePhysicalName(
   }
   return evaluateCfnTemplate.findPhysicalNameFor(logicalId);
 }
+
+/**
+ * This function transforms all keys (recursively) in the provided `val` object.
+ *
+ * @param val The object whose keys need to be transformed.
+ * @param transform The function that will be applied to each key.
+ * @returns A new object with the same values as `val`, but with all keys transformed according to `transform`.
+ */
+export function transformObjectKeys(val: any, transform: (str: string) => string): any {
+  if (val == null || typeof val !== 'object') {
+    return val;
+  }
+  if (Array.isArray(val)) {
+    return val.map((input: any) => transformObjectKeys(input, transform));
+  }
+  const ret: { [k: string]: any; } = {};
+  for (const [k, v] of Object.entries(val)) {
+    ret[transform(k)] = transformObjectKeys(v, transform);
+  }
+  return ret;
+}
+
+/**
+ * This function lower cases the first character of the string provided.
+ */
+export function lowerCaseFirstCharacter(str: string): string {
+  return str.length > 0 ? `${str[0].toLowerCase()}${str.substr(1)}` : str;
+}

packages/aws-cdk/lib/api/hotswap/ecs-services.ts

@@ -1,6 +1,6 @@
 import * as AWS from 'aws-sdk';
 import { ISDK } from '../aws-auth';
-import { ChangeHotswapImpact, ChangeHotswapResult, establishResourcePhysicalName, HotswapOperation, HotswappableChangeCandidate } from './common';
+import { ChangeHotswapImpact, ChangeHotswapResult, establishResourcePhysicalName, HotswapOperation, HotswappableChangeCandidate, lowerCaseFirstCharacter, transformObjectKeys } from './common';
 import { EvaluateCloudFormationTemplate } from './evaluate-cloudformation-template';
 
 export async function isHotswappableEcsServiceChange(
@@ -90,7 +90,7 @@ class EcsServiceHotswapOperation implements HotswapOperation {
     // Step 1 - update the changed TaskDefinition, creating a new TaskDefinition Revision
     // we need to lowercase the evaluated TaskDef from CloudFormation,
     // as the AWS SDK uses lowercase property names for these
-    const lowercasedTaskDef = lowerCaseFirstCharacterOfObjectKeys(this.taskDefinitionResource);
+    const lowercasedTaskDef = transformObjectKeys(this.taskDefinitionResource, lowerCaseFirstCharacter);
     const registerTaskDefResponse = await sdk.ecs().registerTaskDefinition(lowercasedTaskDef).promise();
     const taskDefRevArn = registerTaskDefResponse.taskDefinition?.taskDefinitionArn;
 
@@ -172,21 +172,3 @@ class EcsServiceHotswapOperation implements HotswapOperation {
     }));
   }
 }
-
-function lowerCaseFirstCharacterOfObjectKeys(val: any): any {
-  if (val == null || typeof val !== 'object') {
-    return val;
-  }
-  if (Array.isArray(val)) {
-    return val.map(lowerCaseFirstCharacterOfObjectKeys);
-  }
-  const ret: { [k: string]: any; } = {};
-  for (const [k, v] of Object.entries(val)) {
-    ret[lowerCaseFirstCharacter(k)] = lowerCaseFirstCharacterOfObjectKeys(v);
-  }
-  return ret;
-}
-
-function lowerCaseFirstCharacter(str: string): string {
-  return str.length > 0 ? `${str[0].toLowerCase()}${str.substr(1)}` : str;
-}