# SignalResource
<a name="API_SignalResource"></a>

Sends a signal to the specified resource with a success or failure status. You can use the `SignalResource` operation in conjunction with a creation policy or update policy. CloudFormation doesn't proceed with a stack creation or update until resources receive the required number of signals or the timeout period is exceeded. The `SignalResource` operation is useful in cases where you want to send signals from anywhere other than an Amazon EC2 instance.

## Request Parameters
<a name="API_SignalResource_RequestParameters"></a>

 For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).

 ** LogicalResourceId **   
The logical ID of the resource that you want to signal. The logical ID is the name of the resource that given in the template.  
Type: String  
Required: Yes

 ** StackName **   
The stack name or unique stack ID that includes the resource that you want to signal.  
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

 ** Status **   
The status of the signal, which is either success or failure. A failure signal causes CloudFormation to immediately fail the stack creation or update.  
Type: String  
Valid Values: `SUCCESS | FAILURE`   
Required: Yes

 ** UniqueId **   
A unique ID of the signal. When you signal Amazon EC2 instances or Auto Scaling groups, specify the instance ID that you are signaling as the unique ID. If you send multiple signals to a single resource (such as signaling a wait condition), each signal requires a different unique ID.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 64.  
Required: Yes

## Errors
<a name="API_SignalResource_Errors"></a>

For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).

## Examples
<a name="API_SignalResource_Examples"></a>

### SignalResource
<a name="API_SignalResource_Example_1"></a>

This example illustrates one usage of SignalResource.

#### Sample Request
<a name="API_SignalResource_Example_1_Request"></a>

```
https://cloudformation.us-east-1.amazonaws.com/
 ?Action=SignalResource
 &LogicalResourceId=MyWaitCondition
 &StackName=AWaitingTestStack
 &Status=SUCCESS
 &UniqueId=test-signal
 &Version=2010-05-15
 &SignatureVersion=2
 &Timestamp=2010-07-27T22%3A26%3A28.000Z
 &AWSAccessKeyId=[AWS Access KeyID]
 &Signature=[Signature]
```

#### Sample Response
<a name="API_SignalResource_Example_1_Response"></a>

```
<SignalResourceResponse xmlns="http://cloudformation.amazonaws.com/doc/2010-05-15/">
  <ResponseMetadata>
    <RequestId>e7d8c346-744b-11e5-b40b-example</RequestId>
  </ResponseMetadata>
</SignalResourceResponse>
```

## See Also
<a name="API_SignalResource_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/cloudformation-2010-05-15/SignalResource) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/cloudformation-2010-05-15/SignalResource)