Invokes a specific Lambda function.
If you are using the versioning feature, you can invoke the specific function version by providing function version or alias name that is pointing to the function version using the Qualifier parameter in the request. If you don't provide the Qualifier parameter, the $LATEST version of the Lambda function is invoked. Invocations occur at least once in response to an event and functions must be idempotent to handle this. For information about the versioning feature, see AWS Lambda Function Versioning and Aliases (http://docs.aws.amazon.com/lambda/latest/dg/versioning-aliases.html).
This operation requires permission for the lambda:InvokeFunction action.