---
url: /rules/no-construct-in-interface.md
---

# no-construct-in-interface

This rule enforces specifying interfaces for read-only resources (e.g. `IBucket`) for properties in an `interface`.

When AWS resource Constructs (e.g. `Bucket`) implement interfaces for read-only resources (e.g. `IBucket`), it is recommended to specify the read-only resource interface (e.g. `IBucket`) for interface properties to help prevent unintended resource modifications.

***

#### 🔧 How to use

::: code-group

```ts [Oxlint]
// oxlint.config.ts
export default defineConfig({
  // ... some configs
  rules: {
    "awscdk/no-construct-in-interface": "error",
  },
});
```

```js [ESLint]
// eslint.config.mjs
export default defineConfig({
  // ... some configs
  rules: {
    "awscdk/no-construct-in-interface": "error",
  },
});
```

:::

#### ✅ Correct Example

```ts
import { IBucket } from "aws-cdk-lib/aws-s3";
import { DockerImageAsset } from "aws-cdk-lib/aws-ecr-assets";
import { MetricFilter } from "aws-cdk-lib/aws-logs";

interface MyConstructProps {
  // ✅ Read-only interfaces (e.g. `IBucket`) can be used
  readonly bucket: IBucket;

  // ✅ Constructs that are not AWS resource constructs (e.g. `DockerImageAsset`) can be used
  readonly asset: DockerImageAsset;

  // ✅ When there is no read-only resource interface, Construct types (e.g. `MetricFilter`) can be used
  readonly metricFilter: MetricFilter;
}
```

#### ❌ Incorrect Example

```ts
import { Bucket } from "aws-cdk-lib/aws-s3";

interface MyConstructProps {
  // ❌ When a read-only resource interface exists, Construct types (e.g. `Bucket`) should not be used
  readonly bucket: Bucket;
}
```