SSM Documents - using output data from a lambda step for another lambda step

Question

I have a SSM document which has its first step to call a Lambda function (getLaunchTemplateData) using "action 'aws:invokeLambdaFunction'".
The lambda function returns a set of data which is displayed on the "Output payload" on that steps results....
{
  "Payload": {
    "LaunchtemplateID": "lt-00972d7c12345678a"
   },
  "StatusCode": 200
}

I'd like to use that output data for a step further below in the document. How can this be achieved?

I have tried adding the "outputs" tag on the 1st step using..
    outputs:
      - Name: LaunchtemplateID
        Selector: $.Payload.LaunchTemplateID
        Type: String

Then using this as the payload for the next step which is another Lambda function...

Payload: '{ "LTID": "{{ getLaunchTemplateData.LaunchtemplateID }}" }'

but i receive this message...

{"FunctionError":"Unhandled","Payload":{"errorMessage": "An error occurred (InvalidLaunchTemplateId.Malformed) when calling the CreateLaunchTemplateVersion operation: The specified launch template ID '{{ getLaunchTemplateData.LaunchtemplateID }}' is malformed."

The Input parameters for the step that fails is not picking up the values..

"{\"LTID\":\"{{ getLaunchTemplateData.LaunchtemplateID }}\"}"

Edward_S · Answer

Hi,

Are the outputs of your Lambda step defined exactly as you referenced in your question?

```
{ "Payload": { "LaunchtemplateID": "lt-00972d7c12345678a" }, "StatusCode": 200 }
```

```
outputs:
  - Name: LaunchtemplateID
    Selector: $.Payload.LaunchTemplateID Type: String
```

If so, double check that you're using the proper case and variable naming. If the payload output is **LaunchtemplateID** the outputs selector should also use the lower-case **t** in **Template** (ie. **$.Payload.LaunchtemplateID** not **$.Payload.LaunchTemplateID**

Kal · Answer

Yes exactly right. It was the lowercase "t".

Thanks for reaching out.

SSM Documents - using output data from a lambda step for another lambda step

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