# Setup locations
prefix <- '/opt/ml'
model_path <- paste(prefix, 'model', sep='/')

# Bring in model file and factor levels
load(paste(model_path, 'mars_model.RData', sep='/'))


#' Ping to show server is there
#' @get /ping
function() {
  return('')}


#' Parse input and return prediction from model
#' @param req The http request sent
#' @post /invocations
function(req) {
  # Read in data
  conn <- textConnection(gsub('\\\\n', '\n', req$postBody))
  data <- read.csv(conn)
  close(conn)
  
  # Convert input to model matrix
  scoring_X <- model.matrix(~., data, xlev=factor_levels)
  
  # Return prediction
  return(paste(predict(mars_model, scoring_X, row.names=FALSE), collapse=','))}