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User Guide

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[ aws . cloudformation ]



Validates a specified template. CloudFormation first checks if the template is valid JSON. If it isn't, CloudFormation checks if the template is valid YAML. If both these checks fail, CloudFormation returns a template validation error.

See also: AWS API Documentation

See 'aws help' for descriptions of global parameters.


[--template-body <value>]
[--template-url <value>]
[--cli-input-json <value>]
[--generate-cli-skeleton <value>]


--template-body (string)

Structure containing the template body with a minimum length of 1 byte and a maximum length of 51,200 bytes. For more information, go to Template Anatomy in the CloudFormation User Guide.

Conditional: You must pass TemplateURL or TemplateBody . If both are passed, only TemplateBody is used.

--template-url (string)

Location of file containing the template body. The URL must point to a template (max size: 460,800 bytes) that is located in an Amazon S3 bucket or a Systems Manager document. For more information, go to Template Anatomy in the CloudFormation User Guide.

Conditional: You must pass TemplateURL or TemplateBody . If both are passed, only TemplateBody is used.

--cli-input-json (string) Performs service operation based on the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, the CLI values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See 'aws help' for descriptions of global parameters.


To validate an AWS CloudFormation template

The following validate-template command validates the sampletemplate.json template:

aws cloudformation validate-template --template-body file://sampletemplate.json


    "Description": "AWS CloudFormation Sample Template S3_Bucket: Sample template showing how to create a publicly accessible S3 bucket. **WARNING** This template creates an S3 bucket. You will be billed for the AWS resources used if you create a stack from this template.",
    "Parameters": [],
    "Capabilities": []

For more information, see Working with AWS CloudFormation Templates in the AWS CloudFormation User Guide.


Parameters -> (list)

A list of TemplateParameter structures.


The TemplateParameter data type.

ParameterKey -> (string)

The name associated with the parameter.

DefaultValue -> (string)

The default value associated with the parameter.

NoEcho -> (boolean)

Flag indicating whether the parameter should be displayed as plain text in logs and UIs.

Description -> (string)

User defined description associated with the parameter.

Description -> (string)

The description found within the template.

Capabilities -> (list)

The capabilities found within the template. If your template contains IAM resources, you must specify the CAPABILITY_IAM or CAPABILITY_NAMED_IAM value for this parameter when you use the CreateStack or UpdateStack actions with your template; otherwise, those actions return an InsufficientCapabilities error.

For more information, see Acknowledging IAM Resources in CloudFormation Templates .


CapabilitiesReason -> (string)

The list of resources that generated the values in the Capabilities response element.

DeclaredTransforms -> (list)

A list of the transforms that are declared in the template.