# CfnGroup

AWS IoT Greengrass seamlessly extends AWS to edge devices so they can act locally on the data they generate, while still using the cloud for management, analytics, and durable storage.

With AWS IoT Greengrass , connected devices can run AWS Lambda functions, execute predictions based on machine learning models, keep device data in sync, and communicate with other devices securely – even when not connected to the internet. For more information, see the [Developer Guide](https://docs.aws.amazon.com/greengrass/v1/developerguide/what-is-gg.html) .

> For AWS Region support, see [CloudFormation Support for AWS IoT Greengrass](https://docs.aws.amazon.com/greengrass/v1/developerguide/cloudformation-support.html) in the *Developer Guide* .

The `AWS::Greengrass::Group` resource represents a group in AWS IoT Greengrass . In the AWS IoT Greengrass API, groups are used to organize your group versions.

Groups can reference multiple group versions. All group versions must be associated with a group. A group version references a device definition version, subscription definition version, and other version types that contain the components you want to deploy to a Greengrass core device.

To deploy a group version, the group version must reference a core definition version that contains one core. Other version types are optionally included, depending on your business need.

> When you create a group, you can optionally include an initial group version. To associate a group version later, create a [`AWS::Greengrass::GroupVersion`](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-greengrass-groupversion.html) resource and specify the ID of this group.
>
> To change group components (such as devices, subscriptions, or functions), you must create new versions. This is because versions are immutable. For example, to add a function, you create a function definition version that contains the new function (and all other functions that you want to deploy). Then you create a group version that references the new function definition version (and all other version types that you want to deploy).

*Deploying a Group Version*

After you create the group version in your CloudFormation template, you can deploy it using the [`aws greengrass create-deployment`](https://docs.aws.amazon.com/greengrass/v1/apireference/createdeployment-post.html) command in the AWS CLI or from the *Greengrass* node in the AWS IoT console. To deploy a group version, you must have a Greengrass service role associated with your AWS account . For more information, see [CloudFormation Support for AWS IoT Greengrass](https://docs.aws.amazon.com/greengrass/v1/developerguide/cloudformation-support.html) in the *Developer Guide* .

Extends: Construct › CfnElement › CfnRefElement › CfnResource › CfnGroup
Implements: IInspectable, ITaggable, IEnvironmentAware, IGroupRef, IConstruct, IDependable

- CloudFormation: [`AWS::Greengrass::Group`](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-resource-greengrass-group.html)
- Source: Generated code
- Type last changed: v2.252.0 · 30 Apr 2026

## Example

```ts
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_greengrass as greengrass } from 'aws-cdk-lib';

declare const tags: any;
const cfnGroup = new greengrass.CfnGroup(this, 'MyCfnGroup', {
  name: 'name',

  // the properties below are optional
  initialVersion: {
    connectorDefinitionVersionArn: 'connectorDefinitionVersionArn',
    coreDefinitionVersionArn: 'coreDefinitionVersionArn',
    deviceDefinitionVersionArn: 'deviceDefinitionVersionArn',
    functionDefinitionVersionArn: 'functionDefinitionVersionArn',
    loggerDefinitionVersionArn: 'loggerDefinitionVersionArn',
    resourceDefinitionVersionArn: 'resourceDefinitionVersionArn',
    subscriptionDefinitionVersionArn: 'subscriptionDefinitionVersionArn',
  },
  roleArn: 'roleArn',
  tags: tags,
});
```

## Initializer

```ts
new CfnGroup(scope: Construct, id: string, props: CfnGroupProps)
```

## Construct Props

- `initialVersion`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnGroup.GroupVersionProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_greengrass.CfnGroup.GroupVersionProperty.html) — The group version to include when the group is created.

  A group version references the Amazon Resource Name (ARN) of a core definition version, device definition version, subscription definition version, and other version types. The group version must reference a core definition version that contains one core. Other version types are optionally included, depending on your business need.

  > To associate a group version after the group is created, create an [`AWS::Greengrass::GroupVersion`](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-greengrass-groupversion.html) resource and specify the ID of this group.

- `name`: string (required) — The name of the group.

- `roleArn`: string — The Amazon Resource Name (ARN) of the IAM role attached to the group.

  This role contains the permissions that Lambda functions and connectors use to interact with other AWS services.

- `tags`: any — Application-specific metadata to attach to the group.

  You can use tags in IAM policies to control access to AWS IoT Greengrass resources. You can also use tags to categorize your resources. For more information, see [Tagging Your AWS IoT Greengrass Resources](https://docs.aws.amazon.com/greengrass/v1/developerguide/tagging.html) in the *Developer Guide* .

  This `Json` property type is processed as a map of key-value pairs. It uses the following format, which is different from most `Tags` implementations in CloudFormation templates.

  ```json
  "Tags": { "KeyName0": "value", "KeyName1": "value", "KeyName2": "value"
  }
  ```

## Properties

- `attrArn`: string — The ARN of the `Group` , such as `arn:aws:greengrass:us-east-1: :/greengrass/definition/groups/1234a5b6-78cd-901e-2fgh-3i45j6k178l9` .

- `attrId`: string — The ID of the `Group` , such as `1234a5b6-78cd-901e-2fgh-3i45j6k178l9` .

- `attrLatestVersionArn`: string — The ARN of the last `GroupVersion` that was added to the `Group` , such as `arn:aws:greengrass:us-east-1: :/greengrass/definition/groups/1234a5b6-78cd-901e-2fgh-3i45j6k178l9/versions/9876ac30-4bdb-4f9d-95af-b5fdb66be1a2` .

- `attrName`: string — The name of the `Group` , such as `MyGroup` .

- `attrRoleArn`: string — The ARN of the IAM role that's attached to the `Group` , such as `arn:aws:iam:: :role/role-name` .

- `attrRoleAttachedAt`: string — The time (in milliseconds since the epoch) when the group role was attached to the `Group` .

- `CFN_RESOURCE_TYPE_NAME`: string (static) — The CloudFormation resource type name for this resource class.

- `cfnOptions`: [ICfnResourceOptions](/cdk/api/v2/docs/aws-cdk-lib.ICfnResourceOptions.html) — Options for this resource, such as condition, update policy etc.

- `cfnResourceType`: string — AWS resource type.

- `creationStack`: string[]

- `env`: [ResourceEnvironment](/cdk/api/v2/docs/aws-cdk-lib.interfaces.ResourceEnvironment.html)

- `groupRef`: [GroupReference](/cdk/api/v2/docs/aws-cdk-lib.interfaces.aws_greengrass.GroupReference.html) — A reference to a Group resource.

- `initialVersion`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnGroup.GroupVersionProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_greengrass.CfnGroup.GroupVersionProperty.html) — The group version to include when the group is created.

- `logicalId`: string — The logical ID for this CloudFormation stack element.

  The logical ID of the element
  is calculated from the path of the resource node in the construct tree.

  To override this value, use `overrideLogicalId(newLogicalId)`.

- `name`: string — The name of the group.

- `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) — The tree node.

- `ref`: string — Return a string that will be resolved to a CloudFormation `{ Ref }` for this element.

  If, by any chance, the intrinsic reference of a resource is not a string, you could
  coerce it to an IResolvable through `Lazy.any({ produce: resource.ref })`.

- `roleArn`: string — The Amazon Resource Name (ARN) of the IAM role attached to the group.

- `stack`: [Stack](/cdk/api/v2/docs/aws-cdk-lib.Stack.html) — The stack in which this element is defined.

  CfnElements must be defined within a stack scope (directly or indirectly).

- `tags`: [TagManager](/cdk/api/v2/docs/aws-cdk-lib.TagManager.html) — Tag Manager which manages the tags for this resource.

- `tagsRaw`: any — Application-specific metadata to attach to the group.

## Methods

- `addDeletionOverride(path: string): void` — Syntactic sugar for `addOverride(path, undefined)`.

  **Parameters**

  - `path` — The path of the value to delete.

- `addDependency(target: CfnResource): void` — Use `addResourceDependency` instead.

  This method has been renamed to `addResourceDependency` to more clearly
  set it apart from `construct.node.addDependency`. See the documentation
  of that function for more details.

- `addDependsOn(target: CfnResource): void` — Use `addResourceDependency` instead.

  This can be used for resources across stacks (or nested stack) boundaries
  and the dependency will automatically be transferred to the relevant scope.

  This method has been renamed to `addResourceDependency`, which makes it
  more clear that this method operates at a different level from the
  construct-level `construct.node.addDependency()` mechanism.

- `addMetadata(key: string, value: any): void` — Add a value to the CloudFormation Resource Metadata.

- `addOverride(path: string, value: any): void` — Adds an override to the synthesized CloudFormation resource.

  To add a
  property override, either use `addPropertyOverride` or prefix `path` with
  "Properties." (i.e. `Properties.TopicName`).

  If the override is nested, separate each nested level using a dot (.) in the path parameter.
  If there is an array as part of the nesting, specify the index in the path.

  To include a literal `.` in the property name, prefix with a `\`. In most
  programming languages you will need to write this as `"\\."` because the
  `\` itself will need to be escaped.

  For example,
  ```typescript
  cfnResource.addOverride('Properties.GlobalSecondaryIndexes.0.Projection.NonKeyAttributes', ['myattribute']);
  cfnResource.addOverride('Properties.GlobalSecondaryIndexes.1.ProjectionType', 'INCLUDE');
  ```
  would add the overrides
  ```json
  "Properties": {
    "GlobalSecondaryIndexes": [
      {
        "Projection": {
          "NonKeyAttributes": [ "myattribute" ]
          ...
        }
        ...
      },
      {
        "ProjectionType": "INCLUDE"
        ...
      },
    ]
    ...
  }
  ```

  The `value` argument to `addOverride` will not be processed or translated
  in any way. Pass raw JSON values in here with the correct capitalization
  for CloudFormation. If you pass CDK classes or structs, they will be
  rendered with lowercased key names, and CloudFormation will reject the
  template.

  **Parameters**

  - `path` — - The path of the property, you can use dot notation to override values in complex types.
  - `value` — - The value.

- `addPropertyDeletionOverride(propertyPath: string): void` — Adds an override that deletes the value of a property from the resource definition.

  **Parameters**

  - `propertyPath` — The path to the property.

- `addPropertyOverride(propertyPath: string, value: any): void` — Adds an override to a resource property.

  Syntactic sugar for `addOverride("Properties.<...>", value)`.

  **Parameters**

  - `propertyPath` — The path of the property.
  - `value` — The value.

- `addResourceDependency(target: CfnResource, reason?: string): void` — Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned.

  This can be used for resources across stacks (or nested stack) boundaries
  and the dependency will automatically be transferred to the relevant scope.

  This method only adds dependencies between L1 resources. If you are
  looking for a generic construct-to-construct dependency mechanism that works
  for all constructs including L2s, use `construct.node.addDependency` instead.

- `applyCrossStackReferenceStrength(strength: ReferenceStrength): void` — Sets the cross-stack reference strength for this resource.

  When set, any cross-stack reference to this resource will use the specified
  strength instead of the global default from the consuming stack's context.

  **Parameters**

  - `strength` — - The reference strength to use for this resource.

- `applyRemovalPolicy(policy?: RemovalPolicy, options?: RemovalPolicyOptions): void` — Sets the deletion policy of the resource based on the removal policy specified.

  The Removal Policy controls what happens to this resource when it stops
  being managed by CloudFormation, either because you've removed it from the
  CDK application or because you've made a change that requires the resource
  to be replaced.

  The resource can be deleted (`RemovalPolicy.DESTROY`), or left in your AWS
  account for data recovery and cleanup later (`RemovalPolicy.RETAIN`). In some
  cases, a snapshot can be taken of the resource prior to deletion
  (`RemovalPolicy.SNAPSHOT`). A list of resources that support this policy
  can be found in the following link:

- `arnForGroup(resource: IGroupRef): string` (static)

- `cfnPropertyName(cdkPropertyName: string): string`

- `fromGroupArn(scope: Construct, id: string, arn: string): IGroupRef` (static) — Creates a new IGroupRef from an ARN.

- `fromGroupId(scope: Construct, id: string, groupId: string): IGroupRef` (static) — Creates a new IGroupRef from a groupId.

- `getAtt(attributeName: string, typeHint?: ResolutionTypeHint): Reference` — Returns a token for an runtime attribute of this resource.

  Ideally, use generated attribute accessors (e.g. `resource.arn`), but this can be used for future compatibility
  in case there is no generated attribute.

  **Parameters**

  - `attributeName` — The name of the attribute.

- `getMetadata(key: string): any` — Retrieve a value value from the CloudFormation Resource Metadata.

- `inspect(inspector: TreeInspector): void` — Examines the CloudFormation resource and discloses attributes.

  **Parameters**

  - `inspector` — tree inspector to collect and process attributes.

- `isCfnElement(x: any): boolean` (static) — Returns `true` if a construct is a stack element (i.e. part of the synthesized cloudformation template).

  Uses duck-typing instead of `instanceof` to allow stack elements from different
  versions of this library to be included in the same stack.

  **Returns:** The construct as a stack element or undefined if it is not a stack element.

- `isCfnGroup(x: any): boolean` (static) — Checks whether the given object is a CfnGroup.

- `isCfnResource(x: any): boolean` (static) — Check whether the given object is a CfnResource.

- `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct.

  Use this method instead of `instanceof` to properly detect `Construct`
  instances, even when the construct library is symlinked.

  Explanation: in JavaScript, multiple copies of the `constructs` library on
  disk are seen as independent, completely different libraries. As a
  consequence, the class `Construct` in each copy of the `constructs` library
  is seen as a different class, and an instance of one class will not test as
  `instanceof` the other class. `npm install` will not create installations
  like this, but users may manually symlink construct libraries together or
  use a monorepo tool: in those cases, multiple copies of the `constructs`
  library can be accidentally installed, and `instanceof` will behave
  unpredictably. It is safest to avoid using `instanceof`, and using
  this type-testing method instead.

  **Parameters**

  - `x` — Any object.

  **Returns:** true if `x` is an object created from a class which extends `Construct`.

- `obtainDependencies(): Stack | CfnResource[]` — Retrieves an array of resources and stacks this resource depends on.

  For resources depended on directly, returns the `CfnResource` object. For
  dependencies on other stacks, returns the `Stack` object. The order of the
  array is not guaranteed.

- `overrideLogicalId(newLogicalId: string): void` — Overrides the auto-generated logical ID with a specific ID.

  **Parameters**

  - `newLogicalId` — The new logical ID to use for this stack element.

- `removeDependency(target: CfnResource): void` — Use `removeResourceDependency` instead

  This can be used for resources across stacks (including nested stacks)
  and the dependency will automatically be removed from the relevant scope.

- `removeResourceDependency(target: CfnResource): void` — Indicates that this resource no longer depends on another resource.

  This can be used for resources across stacks (including nested stacks)
  and the dependency will automatically be removed from the relevant scope.

- `replaceDependency(target: CfnResource, newTarget: CfnResource): void` — Replaces one dependency with another.

  **Parameters**

  - `target` — The dependency to replace.
  - `newTarget` — The new dependency to add.

- `toString(): string` — Returns a string representation of this construct.

  **Returns:** a string representation of this resource

- `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct.

  Mixins are applied in order. The list of constructs is captured at the
  start of the call, so constructs added by a mixin will not be visited.
  Use multiple `with()` calls if subsequent mixins should apply to added
  constructs.