add utility functions

packages/@aws-cdk/aws-s3objectlambda/lib/object-lambda.ts

@@ -1,6 +1,7 @@
 import * as iam from '@aws-cdk/aws-iam';
 import * as lambda from '@aws-cdk/aws-lambda';
 import * as s3 from '@aws-cdk/aws-s3';
+import { Stack } from '@aws-cdk/core';
 import { Construct } from 'constructs';
 import { CfnAccessPoint } from './s3objectlambda.generated';
 
@@ -60,10 +61,15 @@ export interface ObjectLambdaProps {
   * An S3 Object Lambda for intercepting and transforming `GetObject` requests.
   */
 export class ObjectLambda extends CoreConstruct {
+  private readonly objectLambda: CfnAccessPoint
+  private readonly stack: Stack
+
   constructor(scope: Construct, id: string, props: ObjectLambdaProps) {
     super(scope, id);
 
-    const supporting = new s3.CfnAccessPoint(this, 'access-point', {
+    this.stack = props.bucket.stack;
+
+    const supporting = new s3.CfnAccessPoint(this, 'AccessPoint', {
       bucket: props.bucket.bucketName,
       // TODO: configure publicAccessBlockConfiguration?
     });
@@ -76,8 +82,8 @@ export class ObjectLambda extends CoreConstruct {
       allowedFeatures.push('GetObject-Range');
     }
 
-    const objectLambda = new CfnAccessPoint(this, 'lambda-access-point', {
-      name: `${props.fn.functionName}-access-point`,
+    this.objectLambda = new CfnAccessPoint(this, 'LambdaAccessPoint', {
+      name: `${props.fn.functionName.toLowerCase()}-access-point`,
       objectLambdaConfiguration: {
         allowedFeatures,
         cloudWatchMetricsEnabled: props.cloudWatchMetricsEnabled,
@@ -95,7 +101,7 @@ export class ObjectLambda extends CoreConstruct {
         ],
       },
     });
-    objectLambda.addDependsOn(supporting);
+    this.objectLambda.addDependsOn(supporting);
 
     props.fn.addToRolePolicy(
       new iam.PolicyStatement({
@@ -104,4 +110,51 @@ export class ObjectLambda extends CoreConstruct {
       }),
     );
   }
+
+  /**
+   * The ARN of the Object Lambda access point.
+   */
+  get arn(): string {
+    return this.objectLambda.getAtt('Arn').toString();
+  }
+
+  /**
+   * The IPv4 DNS name of the Object Lambda access point.
+   */
+  get domainName(): string {
+    const urlSuffix = this.stack.urlSuffix;
+    return `${this.objectLambda.name}-${this.stack.account}.s3.${urlSuffix}`;
+  }
+
+  /**
+   * The regional domain name of the Object Lambda access point.
+   */
+  get regionalDomainName(): string {
+    const urlSuffix = this.stack.urlSuffix;
+    const region = this.stack.region;
+    return `${this.objectLambda.name}-${this.stack.account}.s3.${region}.${urlSuffix}`;
+  }
+
+  /**
+   * The virtual hosted-style URL of an S3 object through this access point.
+   * Specify `regional: false` at the options for non-regional URL.
+   * @param key The S3 key of the object. If not specified, the URL of the
+   *      bucket is returned.
+   * @param options Options for generating URL.
+   * @returns an ObjectS3Url token
+   */
+  public virtualHostedUrlForObject(key?: string, options?: s3.VirtualHostedStyleUrlOptions): string {
+    const domainName = options?.regional ?? true ? this.regionalDomainName : this.domainName;
+    const prefix = `https://${domainName}`;
+    if (typeof key !== 'string') {
+      return prefix;
+    }
+    if (key.startsWith('/')) {
+      key = key.slice(1);
+    }
+    if (key.endsWith('/')) {
+      key = key.slice(0, -1);
+    }
+    return `${prefix}/${key}`;
+  }
 }

packages/@aws-cdk/aws-s3objectlambda/package.json

@@ -110,4 +110,4 @@
   "publishConfig": {
     "tag": "latest"
   }
-}
+}

packages/@aws-cdk/aws-s3objectlambda/test/integ.s3objectlambda.expected.json

@@ -149,36 +149,26 @@
         "MyFunction2ServiceRole07E5BE0E"
       ]
     },
-    "MyObjectLambda1accesspoint2C407F9B": {
+    "MyObjectLambda1AccessPointD5812646": {
       "Type": "AWS::S3::AccessPoint",
       "Properties": {
         "Bucket": {
           "Ref": "MyBucketF68F3FF0"
         }
       }
     },
-    "MyObjectLambda1lambdaaccesspoint742618A6": {
+    "MyObjectLambda1LambdaAccessPoint73C4BD68": {
       "Type": "AWS::S3ObjectLambda::AccessPoint",
       "Properties": {
-        "Name": {
-          "Fn::Join": [
-            "",
-            [
-              {
-                "Ref": "MyFunction12A744C2E"
-              },
-              "-access-point"
-            ]
-          ]
-        },
+        "Name": "${token[token.87]}-access-point",
         "ObjectLambdaConfiguration": {
           "AllowedFeatures": [
             "GetObject-PartNumber"
           ],
           "CloudWatchMetricsEnabled": true,
           "SupportingAccessPoint": {
             "Fn::GetAtt": [
-              "MyObjectLambda1accesspoint2C407F9B",
+              "MyObjectLambda1AccessPointD5812646",
               "Arn"
             ]
           },
@@ -203,38 +193,28 @@
         }
       },
       "DependsOn": [
-        "MyObjectLambda1accesspoint2C407F9B"
+        "MyObjectLambda1AccessPointD5812646"
       ]
     },
-    "MyObjectLambda2accesspoint757C55B0": {
+    "MyObjectLambda2AccessPoint76FB5ACF": {
       "Type": "AWS::S3::AccessPoint",
       "Properties": {
         "Bucket": {
           "Ref": "MyBucketF68F3FF0"
         }
       }
     },
-    "MyObjectLambda2lambdaaccesspoint16890151": {
+    "MyObjectLambda2LambdaAccessPoint1043EB83": {
       "Type": "AWS::S3ObjectLambda::AccessPoint",
       "Properties": {
-        "Name": {
-          "Fn::Join": [
-            "",
-            [
-              {
-                "Ref": "MyFunction2F2A964CA"
-              },
-              "-access-point"
-            ]
-          ]
-        },
+        "Name": "${token[token.104]}-access-point",
         "ObjectLambdaConfiguration": {
           "AllowedFeatures": [
             "GetObject-Range"
           ],
           "SupportingAccessPoint": {
             "Fn::GetAtt": [
-              "MyObjectLambda2accesspoint757C55B0",
+              "MyObjectLambda2AccessPoint76FB5ACF",
               "Arn"
             ]
           },
@@ -259,7 +239,7 @@
         }
       },
       "DependsOn": [
-        "MyObjectLambda2accesspoint757C55B0"
+        "MyObjectLambda2AccessPoint76FB5ACF"
       ]
     }
   }