Presets

Presets are shared default values that you reference from resource definitions. They reduce repetition when multiple resources of the same type share common configuration.

Defining a Preset

Extract shared properties into exported const declarations:

src/preset-defaults.ts

import { ServerSideEncryptionByDefault, PublicAccessBlockConfiguration } from "@intentius/chant-lexicon-aws";

export const encryptionDefault = new ServerSideEncryptionByDefault({
  SSEAlgorithm: "AES256",
});

export const publicAccessBlock = new PublicAccessBlockConfiguration({
  BlockPublicAcls: true,
  BlockPublicPolicy: true,
  IgnorePublicAcls: true,
  RestrictPublicBuckets: true,
});

Using a Preset

Import the preset and use it in resource properties:

src/preset-usage.ts

import { Bucket, BucketEncryption, ServerSideEncryptionRule, Sub, AWS, Ref } from "@intentius/chant-lexicon-aws";
import { publicAccessBlock, encryptionDefault } from "./preset-defaults";
import { environment } from "./parameters";

export const secureBucket = new Bucket({
  BucketName: Sub`${AWS.StackName}-${Ref(environment)}-secure-data`,
  PublicAccessBlockConfiguration: publicAccessBlock,
  BucketEncryption: new BucketEncryption({
    ServerSideEncryptionConfiguration: [
      new ServerSideEncryptionRule({
        ServerSideEncryptionByDefault: encryptionDefault,
      }),
    ],
  }),
});

Properties listed after the preset reference override the preset values.

Rules

• The spread source must be a const binding. Spreading from let, var, or function calls triggers lint rule EVL004.
• Preset objects are plain data — they are not resource instances.
• Properties in the spread are merged shallowly. Nested objects are replaced entirely, not deep-merged.

See your lexicon’s documentation for working preset examples with concrete resource types.