Action=SendMessage&MessageBody={
    "method": "$context.httpMethod",
    "body-json" : $input.json('$'),
    "queryParams": {
      #foreach($param in $input.params().querystring.keySet())
      "$param": "$util.escapeJavaScript($input.params().querystring.get($param))" #if($foreach.hasNext),#end
    #end
    },
    "pathParams": {
      #foreach($param in $input.params().path.keySet())
      "$param": "$util.escapeJavaScript($input.params().path.get($param))" #if($foreach.hasNext),#end
      #end
    }
}