R Shiny App

app.R

library(httr)
library(shiny)
library(jsonlite)

DEPLOYMENT_ID <- "93562b3a-19d5-42db-a52a-f4846dd7d487"
VERSION <- "2022-09-27"
SPACE_ID = "399a2bce-40b5-457a-8e18-de978043e2c8"
API_KEY = "xxx"
CPD_URL = "https://cpd-cpd.itzroks-550003aw18-rmaez9-6ccd7f378ae819553d37d5f2ee142bd6-0000.au-syd.containers.appdomain.cloud"
USERNAME = "admin"
httr::set_config(httr::config(ssl_verifypeer = FALSE, ssl_verifyhost = FALSE))

getHeaders <- function() {
  headers <- c("cache-control"="no-cache", "Content-Type"="application/json")
  url <- stringr::str_interp("${CPD_URL}/icp4d-api/v1/authorize")
  body <- stringr::str_interp('{"username":"${USERNAME}","api_key":"${API_KEY}"}')
  r <- POST(
    url,
    add_headers(
      .headers = headers
    ),
    body=fromJSON(body),
    encode="json"
  )
  token <- httr::content(r)$token
  headers <- c("Authorization"=stringr::str_interp("Bearer ${token}"), "Content-Type"="application/json", "Accept"="application/json")
  return(headers)
}

ui <- function(req) {
 
  if (identical(req$REQUEST_METHOD, "GET")) {
    htmlTemplate("index.html")
  } else if (identical(req$REQUEST_METHOD, "POST")) {
    body <- rawToChar(req$rook.input$read(-1))   
    url <- stringr::str_interp("${CPD_URL}/ml/v4/deployments/${DEPLOYMENT_ID}/predictions")
    query <- list(version=VERSION)
    r <- POST(
      url,
      add_headers(
        .headers = getHeaders()
      ),
      query=query,
      body=body,
      encode="raw"
    )
    content <- jsonlite::toJSON(
      list(
        fields = unlist(httr::content(r)$predictions[[1]]$fields),
        values = lapply(httr::content(r)$predictions[[1]]$values, unlist)
      )
    )
    httpResponse(
      status = 200L,
      content_type = "application/json",
      content = content
    )
  }
  
}

attr(ui, "http_methods_supported") <- c("GET", "POST")

server <- function(input, output) { }

addResourcePath("static", "static")

shinyApp(ui = ui, server = server)