portfolio <- list.files(path = "./portfolio")
thumb <- list.files(path = "./thumb")

images <- data.frame(thumb, portfolio)

images %>%
  jsonlite::toJSON() %>%
  write(file="./images.json")
iframesource <- list.files(path = "./iframes", pattern = ".html")
iframethumb <- list.files(path = "./iframethumb")
iframe <- data.frame(iframethumb, iframesource)

iframe %>%
  jsonlite::toJSON() %>%
  write(file="./iframe.json")