feat(s3-deployment): prune - keep missing files on destination bucket

packages/@aws-cdk/assert/jest.ts

@@ -1,5 +1,6 @@
 import * as core from '@aws-cdk/core';
 import * as cxapi from '@aws-cdk/cx-api';
+import { countResources } from './lib';
 import { JestFriendlyAssertion } from './lib/assertion';
 import { haveOutput, HaveOutputProperties } from './lib/assertions/have-output';
 import { HaveResourceAssertion, ResourcePart } from './lib/assertions/have-resource';
@@ -25,6 +26,8 @@ declare global {
         comparison?: ResourcePart): R;
 
       toHaveOutput(props: HaveOutputProperties): R;
+
+      toCountResources(resourceType: string, count: number): R;
     }
   }
 }
@@ -77,6 +80,14 @@ expect.extend({
 
     return applyAssertion(haveOutput(props), actual);
   },
+
+  toCountResources(
+    actual: cxapi.CloudFormationStackArtifact | core.Stack,
+    resourceType: string,
+    count = 1) {
+
+    return applyAssertion(countResources(resourceType, count), actual);
+  },
 });
 
 function applyAssertion(assertion: JestFriendlyAssertion<StackInspector>, actual: cxapi.CloudFormationStackArtifact | core.Stack) {

packages/@aws-cdk/assert/lib/assertions/count-resources.ts

@@ -1,11 +1,11 @@
-import { Assertion } from '../assertion';
+import { Assertion, JestFriendlyAssertion } from '../assertion';
 import { StackInspector } from '../inspector';
 import { isSuperObject } from './have-resource';
 
 /**
  * An assertion to check whether a resource of a given type and with the given properties exists, disregarding properties
  */
-export function countResources(resourceType: string, count = 1): Assertion<StackInspector> {
+export function countResources(resourceType: string, count = 1): JestFriendlyAssertion<StackInspector> {
   return new CountResourcesAssertion(resourceType, count);
 }
 
@@ -16,7 +16,7 @@ export function countResourcesLike(resourceType: string, count = 1, props: any):
   return new CountResourcesAssertion(resourceType, count, props);
 }
 
-class CountResourcesAssertion extends Assertion<StackInspector> {
+class CountResourcesAssertion extends JestFriendlyAssertion<StackInspector> {
   private inspected: number = 0;
   private readonly props: any;
 
@@ -48,6 +48,10 @@ class CountResourcesAssertion extends Assertion<StackInspector> {
     return counted === this.count;
   }
 
+  public generateErrorMessage(): string {
+    return this.description;
+  }
+
   public get description(): string {
     return `stack only has ${this.inspected} resource of type ${this.resourceType}${this.props ? ' with specified properties' : ''} but we expected to find ${this.count}`;
   }

packages/@aws-cdk/aws-s3-deployment/.gitignore

@@ -18,3 +18,5 @@ nyc.config.js
 
 *.snk
 !.eslintrc.js
+
+!jest.config.js

packages/@aws-cdk/aws-s3-deployment/.npmignore

@@ -22,5 +22,6 @@ lambda/*.sh
 tsconfig.json
 .eslintrc.js
 
+jest.config.js
 # exclude cdk artifacts
-**/cdk.out
+**/cdk.out

packages/@aws-cdk/aws-s3-deployment/README.md

@@ -41,7 +41,7 @@ This is what happens under the hood:
    is set to point to the assets bucket.
 3. The custom resource downloads the .zip archive, extracts it and issues `aws
    s3 sync --delete` against the destination bucket (in this case
-   `websiteBucket`). If there is more than one source, the sources will be 
+   `websiteBucket`). If there is more than one source, the sources will be
    downloaded and merged pre-deployment at this step.
 
 ## Supported sources
@@ -59,10 +59,44 @@ all but a single file:
 
 ## Retain on Delete
 
-By default, the contents of the destination bucket will be deleted when the
+By default, the contents of the destination bucket will **not** be deleted when the
 `BucketDeployment` resource is removed from the stack or when the destination is
-changed. You can use the option `retainOnDelete: true` to disable this behavior,
-in which case the contents will be retained.
+changed. You can use the option `retainOnDelete: false` to disable this behavior,
+in which case the contents will be deleted.
+
+## Prune
+
+By default, files in the destination bucket that don't exist in the source will be deleted
+when the `BucketDeployment` resource is created or updated. You can use the option `prune: false` to disable
+this behavior, in which case the files will not be deleted.
+
+```typescript
+new s3deploy.BucketDeployment(this, 'DeployMeWithoutDeletingFilesOnDestination', {
+  sources: [s3deploy.Source.asset(path.join(__dirname, 'my-website'))],
+  destinationBucket,
+  prune: false,
+});
+```
+
+This option also enables you to specify multiple bucket deployments for the same destination bucket & prefix,
+each with its own characteristics. For example, you can set different cache-control headers
+based on file extensions:
+
+```typescript
+new BucketDeployment(this, 'BucketDeployment', {
+  sources: [Source.asset('./website', { exclude: ['index.html' })],
+  destinationBucket: bucket,
+  cacheControl: [CacheControl.fromString('max-age=31536000,public,immutable')],
+  prune: false,
+});
+
+new BucketDeployment(this, 'HTMLBucketDeployment', {
+  sources: [Source.asset('./website', { exclude: ['!index.html'] })],
+  destinationBucket: bucket,
+  cacheControl: [CacheControl.fromString('max-age=0,no-cache,no-store,must-revalidate')],
+  prune: false,
+});
+```
 
 ## Objects metadata
 

packages/@aws-cdk/aws-s3-deployment/jest.config.js

@@ -0,0 +1,2 @@
+const baseConfig = require('../../../tools/cdk-build-tools/config/jest.config');
+module.exports = baseConfig;

packages/@aws-cdk/aws-s3-deployment/lambda/src/index.py

@@ -47,6 +47,7 @@ def cfn_error(message=None):
             distribution_id     = props.get('DistributionId', '')
             user_metadata       = props.get('UserMetadata', {})
             system_metadata     = props.get('SystemMetadata', {})
+            prune               = props.get('Prune', 'true').lower() == 'true'
 
             default_distribution_path = dest_bucket_prefix
             if not default_distribution_path.endswith("/"):
@@ -98,7 +99,7 @@ def cfn_error(message=None):
             aws_command("s3", "rm", old_s3_dest, "--recursive")
 
         if request_type == "Update" or request_type == "Create":
-            s3_deploy(s3_source_zips, s3_dest, user_metadata, system_metadata)
+            s3_deploy(s3_source_zips, s3_dest, user_metadata, system_metadata, prune)
 
         if distribution_id:
             cloudfront_invalidate(distribution_id, distribution_paths)
@@ -112,7 +113,7 @@ def cfn_error(message=None):
 
 #---------------------------------------------------------------------------------------------------
 # populate all files from s3_source_zips to a destination bucket
-def s3_deploy(s3_source_zips, s3_dest, user_metadata, system_metadata):
+def s3_deploy(s3_source_zips, s3_dest, user_metadata, system_metadata, prune):
     # create a temporary working directory
     workdir=tempfile.mkdtemp()
     logger.info("| workdir: %s" % workdir)
@@ -131,7 +132,16 @@ def s3_deploy(s3_source_zips, s3_dest, user_metadata, system_metadata):
           zip.extractall(contents_dir)
 
     # sync from "contents" to destination
-    aws_command("s3", "sync", "--delete", contents_dir, s3_dest, *create_metadata_args(user_metadata, system_metadata))
+
+    s3_command = ["s3", "sync"]
+
+    if prune:
+      s3_command.append("--delete")
+
+    s3_command.extend([contents_dir, s3_dest])
+    s3_command.extend(create_metadata_args(user_metadata, system_metadata))
+    aws_command(*s3_command)
+
     shutil.rmtree(workdir)
 
 #---------------------------------------------------------------------------------------------------

packages/@aws-cdk/aws-s3-deployment/lambda/test/aws

@@ -21,7 +21,7 @@ if sys.argv[2] == "cp" and not sys.argv[4].startswith("s3://"):
     sys.argv[4] = "archive.zip"
 
 if sys.argv[2] == "sync":
-    sys.argv[4] = "contents.zip"
+    sys.argv[4 if '--delete' in sys.argv else 3] = "contents.zip"
 
 with open("./aws.out", "a") as myfile:
     myfile.write(json.dumps(sys.argv[1:]) + "\n")

packages/@aws-cdk/aws-s3-deployment/lambda/test/test.py

@@ -16,7 +16,7 @@
 class TestHandler(unittest.TestCase):
     def setUp(self):
         logger = logging.getLogger()
-        
+
         # clean up old aws.out file (from previous runs)
         try: os.remove("aws.out")
         except OSError: pass
@@ -37,6 +37,34 @@ def test_create_update(self):
             ["s3", "sync", "--delete", "contents.zip", "s3://<dest-bucket-name>/"]
         )
 
+    def test_create_no_delete(self):
+        invoke_handler("Create", {
+            "SourceBucketNames": ["<source-bucket>"],
+            "SourceObjectKeys": ["<source-object-key>"],
+            "DestinationBucketName": "<dest-bucket-name>",
+            "Prune": "false"
+        })
+
+        self.assertAwsCommands(
+            ["s3", "cp", "s3://<source-bucket>/<source-object-key>", "archive.zip"],
+            ["s3", "sync", "contents.zip", "s3://<dest-bucket-name>/"]
+        )
+
+    def test_update_no_delete(self):
+        invoke_handler("Update", {
+            "SourceBucketNames": ["<source-bucket>"],
+            "SourceObjectKeys": ["<source-object-key>"],
+            "DestinationBucketName": "<dest-bucket-name>",
+            "Prune": "false"
+        }, old_resource_props={
+            "DestinationBucketName": "<dest-bucket-name>",
+        }, physical_id="<physical-id>")
+
+        self.assertAwsCommands(
+            ["s3", "cp", "s3://<source-bucket>/<source-object-key>", "archive.zip"],
+            ["s3", "sync", "contents.zip", "s3://<dest-bucket-name>/"]
+        )
+
     def test_create_update_multiple_sources(self):
         invoke_handler("Create", {
             "SourceBucketNames": ["<source-bucket1>", "<source-bucket2>"],

packages/@aws-cdk/aws-s3-deployment/lib/bucket-deployment.ts

@@ -30,6 +30,16 @@ export interface BucketDeploymentProps {
    */
   readonly destinationKeyPrefix?: string;
 
+  /**
+   * If this is set to false, files in the destination bucket that
+   * do not exist in the asset, will NOT be deleted during deployment (create/update).
+   *
+   * @see https://docs.aws.amazon.com/cli/latest/reference/s3/sync.html
+   *
+   * @default true
+   */
+  readonly prune?: boolean
+
   /**
    * If this is set to "false", the destination files will be deleted when the
    * resource is deleted or the destination is updated.
@@ -197,12 +207,14 @@ export class BucketDeployment extends cdk.Construct {
         DestinationBucketName: props.destinationBucket.bucketName,
         DestinationBucketKeyPrefix: props.destinationKeyPrefix,
         RetainOnDelete: props.retainOnDelete,
+        Prune: props.prune ?? true,
         UserMetadata: props.metadata ? mapUserMetadata(props.metadata) : undefined,
         SystemMetadata: mapSystemMetadata(props),
         DistributionId: props.distribution ? props.distribution.distributionId : undefined,
         DistributionPaths: props.distributionPaths,
       },
     });
+
   }
 
   private renderSingletonUuid(memoryLimit?: number) {

packages/@aws-cdk/aws-s3-deployment/package.json

@@ -51,7 +51,8 @@
     ],
     "test": [
       "/bin/bash lambda/test.sh"
-    ]
+    ],
+    "jest": true
   },
   "keywords": [
     "aws",
@@ -77,10 +78,10 @@
   "license": "Apache-2.0",
   "devDependencies": {
     "@aws-cdk/assert": "0.0.0",
-    "@types/nodeunit": "^0.0.31",
+    "@types/jest": "^25.2.3",
     "cdk-build-tools": "0.0.0",
     "cdk-integ-tools": "0.0.0",
-    "nodeunit": "^0.11.3",
+    "jest": "^25.5.4",
     "pkglint": "0.0.0"
   },
   "dependencies": {