CreateChangeSet - AWS CloudFormation

CreateChangeSet

Creates a list of changes that will be applied to a stack so that you can review the changes before executing them. You can create a change set for a stack that doesn't exist or an existing stack. If you create a change set for a stack that doesn't exist, the change set shows all of the resources that CloudFormation will create. If you create a change set for an existing stack, CloudFormation compares the stack's information with the information that you submit in the change set and lists the differences. Use change sets to understand which resources CloudFormation will create or change, and how it will change resources in an existing stack, before you create or update a stack.

To create a change set for a stack that doesn't exist, for the ChangeSetType parameter, specify CREATE. To create a change set for an existing stack, specify UPDATE for the ChangeSetType parameter. To create a change set for an import operation, specify IMPORT for the ChangeSetType parameter. After the CreateChangeSet call successfully completes, CloudFormation starts creating the change set. To check the status of the change set or to review it, use the DescribeChangeSet action.

When you are satisfied with the changes the change set will make, execute the change set by using the ExecuteChangeSet action. CloudFormation doesn't make changes until you execute the change set.

To create a change set for the entire stack hierarchy, set IncludeNestedStacks to True.

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

Capabilities.member.N

In some cases, you must explicitly acknowledge that your stack template contains certain capabilities in order for CloudFormation to create the stack.

  • CAPABILITY_IAM and CAPABILITY_NAMED_IAM

    Some stack templates might include resources that can affect permissions in your AWS account; for example, by creating new IAM users. For those stacks, you must explicitly acknowledge this by specifying one of these capabilities.

    The following IAM resources require you to specify either the CAPABILITY_IAM or CAPABILITY_NAMED_IAM capability.

    • If you have IAM resources, you can specify either capability.

    • If you have IAM resources with custom names, you must specify CAPABILITY_NAMED_IAM.

    • If you don't specify either of these capabilities, CloudFormation returns an InsufficientCapabilities error.

    If your stack template contains these resources, we suggest that you review all permissions associated with them and edit their permissions if necessary.

    For more information, see Acknowledging IAM resources in CloudFormation templates.

  • CAPABILITY_AUTO_EXPAND

    Some template contain macros. Macros perform custom processing on templates; this can include simple actions like find-and-replace operations, all the way to extensive transformations of entire templates. Because of this, users typically create a change set from the processed template, so that they can review the changes resulting from the macros before actually creating the stack. If your stack template contains one or more macros, and you choose to create a stack directly from the processed template, without first reviewing the resulting changes in a change set, you must acknowledge this capability. This includes the AWS::Include and AWS::Serverless transforms, which are macros hosted by CloudFormation.

    Note

    This capacity doesn't apply to creating change sets, and specifying it when creating change sets has no effect.

    If you want to create a stack from a stack template that contains macros and nested stacks, you must create or update the stack directly from the template using the CreateStack or UpdateStack action, and specifying this capability.

    For more information about macros, see Perform custom processing on CloudFormation templates with template macros.

Note

Only one of the Capabilities and ResourceType parameters can be specified.

Type: Array of strings

Valid Values: CAPABILITY_IAM | CAPABILITY_NAMED_IAM | CAPABILITY_AUTO_EXPAND

Required: No

ChangeSetName

The name of the change set. The name must be unique among all change sets that are associated with the specified stack.

A change set name can contain only alphanumeric, case sensitive characters, and hyphens. It must start with an alphabetical character and can't exceed 128 characters.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 128.

Pattern: [a-zA-Z][-a-zA-Z0-9]*

Required: Yes

ChangeSetType

The type of change set operation. To create a change set for a new stack, specify CREATE. To create a change set for an existing stack, specify UPDATE. To create a change set for an import operation, specify IMPORT.

If you create a change set for a new stack, CloudFormation creates a stack with a unique stack ID, but no template or resources. The stack will be in the REVIEW_IN_PROGRESS state until you execute the change set.

By default, CloudFormation specifies UPDATE. You can't use the UPDATE type to create a change set for a new stack or the CREATE type to create a change set for an existing stack.

Type: String

Valid Values: CREATE | UPDATE | IMPORT

Required: No

ClientToken

A unique identifier for this CreateChangeSet request. Specify this token if you plan to retry requests so that CloudFormation knows that you're not attempting to create another change set with the same name. You might retry CreateChangeSet requests to ensure that CloudFormation successfully received them.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 128.

Required: No

Description

A description to help you identify this change set.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 1024.

Required: No

ImportExistingResources

Indicates if the change set imports resources that already exist.

Note

This parameter can only import resources that have custom names in templates. For more information, see name type in the AWS CloudFormation User Guide. To import resources that do not accept custom names, such as EC2 instances, use the resource import feature instead. For more information, see Import AWS resources into a CloudFormation stack with a resource import in the AWS CloudFormation User Guide.

Type: Boolean

Required: No

IncludeNestedStacks

Creates a change set for the all nested stacks specified in the template. The default behavior of this action is set to False. To include nested sets in a change set, specify True.

Type: Boolean

Required: No

NotificationARNs.member.N

The Amazon Resource Names (ARNs) of Amazon SNS topics that CloudFormation associates with the stack. To remove all associated notification topics, specify an empty list.

Type: Array of strings

Array Members: Maximum number of 5 items.

Required: No

OnStackFailure

Determines what action will be taken if stack creation fails. If this parameter is specified, the DisableRollback parameter to the ExecuteChangeSet API operation must not be specified. This must be one of these values:

  • DELETE - Deletes the change set if the stack creation fails. This is only valid when the ChangeSetType parameter is set to CREATE. If the deletion of the stack fails, the status of the stack is DELETE_FAILED.

  • DO_NOTHING - if the stack creation fails, do nothing. This is equivalent to specifying true for the DisableRollback parameter to the ExecuteChangeSet API operation.

  • ROLLBACK - if the stack creation fails, roll back the stack. This is equivalent to specifying false for the DisableRollback parameter to the ExecuteChangeSet API operation.

For nested stacks, when the OnStackFailure parameter is set to DELETE for the change set for the parent stack, any failure in a child stack will cause the parent stack creation to fail and all stacks to be deleted.

Type: String

Valid Values: DO_NOTHING | ROLLBACK | DELETE

Required: No

Parameters.member.N

A list of Parameter structures that specify input parameters for the change set. For more information, see the Parameter data type.

Type: Array of Parameter objects

Required: No

ResourcesToImport.member.N

The resources to import into your stack.

Type: Array of ResourceToImport objects

Array Members: Maximum number of 200 items.

Required: No

ResourceTypes.member.N

The template resource types that you have permissions to work with if you execute this change set, such as AWS::EC2::Instance, AWS::EC2::*, or Custom::MyCustomInstance.

If the list of resource types doesn't include a resource type that you're updating, the stack update fails. By default, CloudFormation grants permissions to all resource types. IAM uses this parameter for condition keys in IAM policies for CloudFormation. For more information, see Control access with AWS Identity and Access Management in the AWS CloudFormation User Guide.

Note

Only one of the Capabilities and ResourceType parameters can be specified.

Type: Array of strings

Length Constraints: Minimum length of 1. Maximum length of 256.

Required: No

RoleARN

The Amazon Resource Name (ARN) of an IAM role that CloudFormation assumes when executing the change set. CloudFormation uses the role's credentials to make calls on your behalf. CloudFormation uses this role for all future operations on the stack. Provided that users have permission to operate on the stack, CloudFormation uses this role even if the users don't have permission to pass it. Ensure that the role grants least permission.

If you don't specify a value, CloudFormation uses the role that was previously associated with the stack. If no role is available, CloudFormation uses a temporary session that is generated from your user credentials.

Type: String

Length Constraints: Minimum length of 20. Maximum length of 2048.

Required: No

RollbackConfiguration

The rollback triggers for CloudFormation to monitor during stack creation and updating operations, and for the specified monitoring period afterwards.

Type: RollbackConfiguration object

Required: No

StackName

The name or the unique ID of the stack for which you are creating a change set. CloudFormation generates the change set by comparing this stack's information with the information that you submit, such as a modified template or different parameter input values.

Type: String

Length Constraints: Minimum length of 1.

Pattern: ([a-zA-Z][-a-zA-Z0-9]*)|(arn:\b(aws|aws-us-gov|aws-cn)\b:[-a-zA-Z0-9:/._+]*)

Required: Yes

Tags.member.N

Key-value pairs to associate with this stack. CloudFormation also propagates these tags to resources in the stack. You can specify a maximum of 50 tags.

Type: Array of Tag objects

Array Members: Maximum number of 50 items.

Required: No

TemplateBody

A structure that contains the body of the revised template, with a minimum length of 1 byte and a maximum length of 51,200 bytes. CloudFormation generates the change set by comparing this template with the template of the stack that you specified.

Conditional: You must specify only TemplateBody or TemplateURL.

Type: String

Length Constraints: Minimum length of 1.

Required: No

TemplateURL

The location of the file that contains the revised template. The URL must point to a template (max size: 460,800 bytes) that's located in an Amazon S3 bucket or a Systems Manager document. CloudFormation generates the change set by comparing this template with the stack that you specified. The location for an Amazon S3 bucket must start with https://.

Conditional: You must specify only TemplateBody or TemplateURL.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 1024.

Required: No

UsePreviousTemplate

Whether to reuse the template that's associated with the stack to create the change set.

Type: Boolean

Required: No

Response Elements

The following elements are returned by the service.

Id

The Amazon Resource Name (ARN) of the change set.

Type: String

Length Constraints: Minimum length of 1.

Pattern: arn:[-a-zA-Z0-9:/]*

StackId

The unique ID of the stack.

Type: String

Errors

For information about the errors that are common to all actions, see Common Errors.

AlreadyExists

The resource with the name requested already exists.

HTTP Status Code: 400

InsufficientCapabilities

The template contains resources with capabilities that weren't specified in the Capabilities parameter.

HTTP Status Code: 400

LimitExceeded

The quota for the resource has already been reached.

For information about resource and stack limitations, see AWS CloudFormation quotas in the AWS CloudFormation User Guide.

HTTP Status Code: 400

Examples

CreateChangeSet

This example illustrates one usage of CreateChangeSet.

Sample Request

https://cloudformation.us-east-1.amazonaws.com/ ?Action=CreateChangeSet &ChangeSetName=SampleChangeSet &Parameters.member.1.ParameterKey=KeyName &Parameters.member.1.UsePreviousValue=true &Parameters.member.2.ParameterKey=Purpose &Parameters.member.2.ParameterValue=production &StackName=arn:aws:cloudformation:us-east-1:123456789012:stack/SampleStack/1a2345b6-0000-00a0-a123-00abc0abc000 &UsePreviousTemplate=true &Version=2010-05-15 &X-Amz-Algorithm=AWS4-HMAC-SHA256 &X-Amz-Credential=[Access key ID and scope] &X-Amz-Date=20160316T233349Z &X-Amz-SignedHeaders=content-type;host &X-Amz-Signature=[Signature]

Sample Response

<CreateChangeSetResponse xmlns="http://cloudformation.amazonaws.com/doc/2010-05-15/"> <CreateChangeSetResult> <Id>arn:aws:cloudformation:us-east-1:123456789012:changeSet/SampleChangeSet/12a3b456-0e10-4ce0-9052-5d484a8c4e5b</Id> </CreateChangeSetResult> <ResponseMetadata> <RequestId>b9b4b068-3a41-11e5-94eb-example</RequestId> </ResponseMetadata> </CreateChangeSetResponse>

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: