How do i pass a the value of an output from your Cloudformation template to your pipeline as variable

To pass the value of an output from your CloudFormation template to your pipeline as a variable and then use it in subsequent actions like running CodeBuild, you can follow these general steps:

1. Define CloudFormation Output: In your CloudFormation template, define an output for the value you want to pass to the pipeline.

   Outputs:
     MyOutput:
       Description: My output value
       Value: !Ref SomeResource

2. Configure AWS CodePipeline: Set up your AWS CodePipeline with the appropriate stages and actions. Ensure that the CodePipeline has the necessary permissions to access the CloudFormation stack.

3. Start Pipeline: Create a stage in your pipeline where you trigger the CloudFormation stack deployment.

4. Run CloudFormation Template: Add an action to your pipeline to deploy the CloudFormation stack. In the input artifacts section of this action, specify any artifacts needed to deploy the CloudFormation template (such as the template itself or related files).

5. Extract Output from CloudFormation Deployment: After deploying the CloudFormation stack, you need to extract the output value from the stack. You can use a Lambda function or an AWS CLI command in an AWS CodeBuild action to extract the output value. For example, using AWS CLI:

   aws cloudformation describe-stacks --stack-name YourStackName --query "Stacks[0].Outputs[?OutputKey=='MyOutput'].OutputValue" --output text

   This command retrieves the value of the output named MyOutput from the CloudFormation stack named YourStackName.

6. Pass Output as Variable to CodeBuild: Store the output value as an environment variable or parameter that can be accessed by your CodeBuild project. You can achieve this by using the env section in the CodeBuild configuration or by passing it as a parameter when triggering the CodeBuild project from your pipeline.

7. Run CodeBuild: Add a CodeBuild action to your pipeline where you specify the CodeBuild project to run. Use the output value retrieved from the CloudFormation stack as an input variable or parameter for the CodeBuild project.

8. End Pipeline: Optionally, add any additional stages or actions you need in your pipeline. This could include deployment to additional environments, testing, or notifications.

By following these steps, you should be able to pass the value of an output from your CloudFormation template to your pipeline as a variable and use it in subsequent actions like running CodeBuild. Adjustments might be necessary based on your specific pipeline setup and requirements.