Enable Plotly plots in knitr-powered Jekyll

plotly_plot_maker.R

plotly_manager <- function(
  postdir = knitr::opts_chunk$get("plotly.savepath"), # I have this as a default knitr option. Either change or specify your own when you call it 
  basedir = knitr::opts_chunk$get("proj.basedir"),    # Ditto. See: https://www.zachburchill.ml/plotly_with_jekyll/ for explanation
  libdirname = "js_files/",
  hrefFilter = function(x) paste0("/", x)) {
  
  deps <- list()
  libdir <- paste0(postdir, libdirname)
  
  render_deps <- function(l) {
    if (length(l) > 0)
      dir.create(libdir, showWarnings = FALSE, recursive = TRUE)
    l <- lapply(unique(l), function(dep) {
      dep <- htmltools::copyDependencyToDir(dep, libdir, FALSE)
      dep <- htmltools::makeDependencyRelative(dep, basedir, FALSE)
      dep } )
    l <- htmltools::renderDependencies(l, hrefFilter=hrefFilter)
    htmltools::htmlPreserve(l)
  }
  
  add_deps_from_plot <- function(p) {
    deps <<- append(deps, htmltools::renderTags(p)$dependencies)
  }
  
  plot_plotly <- function(p) {
    add_deps_from_plot(p)
    htmltools::tagList(list(plotly::as_widget(p)))
  }
  
  prev_doc_hook <- knitr::knit_hooks$get("document")
  knitr::knit_hooks$set(document = function(x) {
    prev_doc_hook(append(x, render_deps(deps)))
  })
  
  plot_plotly
}

# # Use it like:
# ```{r}
# plot_plotly <- plotly_manager()
# p <- ggplot2::qplot(x=1,y=1)
# p <- plotly::ggplotly(p)
# ```
# # And then:
# ```{r}
# plot_plotly(p)
# ```