R/serverless_predictor.R

In DyfanJones/sagemaker-r-mlcore: sagemaker machine learning core classes and methods

#' # NOTE: This code has been modified from AWS Sagemaker Python:
#' # https://github.com/aws/sagemaker-python-sdk/blob/master/src/sagemaker/serverless/predictor.py
#'
#' #' @include r_utils.R
#' #' @include deserializers.R
#' #' @include serializers.R
#' #' @include predictor.R
#'
#' #' @import R6
#' #' @import paws
#'
#' #' @title LamdbaPredictor
#' #' @description A deployed model hosted on Lambda.
#' #' @export
#' LambdaPredictor = R6Class("LambdaPredictor",
#'   inherit = PredictorBase,
#'   public = list(
#'
#'     #' @description Initialize instance attributes.
#'     #' @param function_name : The name of the function.
#'     #' @param client : The Lambda client used to interact with Lambda.
#'     initialize = function(function_name,
#'                           client=NULL){
#'       private$.client = client %||% paws::lambda()
#'       private$.function_name = function_name
#'       private$.serializer = JSONSerializer$new()
#'       private$.deserializer = JSONDeserializer$new()
#'     },
#'
#'     #' @description Invoke the Lambda function specified in the constructor.
#'     #'              This function is synchronous. It will only return after the function
#'     #'              has produced a prediction.
#'     #' @param data : The data sent to the Lambda function as input.
#'     #' @return The data returned by the Lambda function.
#'     predict = function(data){
#'       response = private$.client$invoke(
#'         FunctionName=private$.function_name,
#'         InvocationType="RequestResponse",
#'         Payload=private$.serializer$serialize(data)
#'       )
#'       return(private$.deserializer$deserialize(
#'         response[["Payload"]],
#'         response[["ResponseMetadata"]][["HTTPHeaders"]][["content-type"]])
#'       )
#'     },
#'
#'     #' @description Destroy the Lambda function specified in the constructor.
#'     delete_predictor = function(){
#'       return(private$.client$delete_function(FunctionName=private$.function_name))
#'     }
#'   ),
#'   active = list(
#'
#'     #' @field content_type
#'     #' The MIME type of the data sent to the Lambda function.
#'     content_type = function(){
#'       return(private$.serializer$CONTENT_TYPE)
#'     },
#'
#'     #' @field accept
#'     #' The content type(s) that are expected from the Lambda function.
#'     accept = function(){
#'       return(private$.deserializer$ACCEPT)
#'     },
#'
#'     #' @field function_name
#'     #' The name of the Lambda function this predictor invokes.
#'     function_name = function(){
#'       return(private$.function_name)
#'     }
#'   )
#' )