Add random replication of quiz questions

Resolves #16

DESCRIPTION

@@ -25,7 +25,6 @@ Imports:
     knitr,
     rlang,
     rmarkdown,
-    stringr,
     xfun,
     yaml
 URL: https://github.com/emitanaka/moodlequiz,

NAMESPACE

@@ -9,4 +9,5 @@ export(cloze_numerical)
 export(cloze_shortanswer)
 export(cloze_singlechoice)
 export(moodlequiz)
+export(moodlequiz_xml)
 import(rmarkdown)

R/quiz-xml.R

@@ -24,10 +24,49 @@ moodlequiz <- function(replicates = 1L,
                        ...) {
   pre_knit <- function (input, ...) {
     output <- tempfile(fileext = ".xml")
-    rmarkdown::render(
-      input, output_format = "moodlequiz_xml", output_file = output, quiet = TRUE
+
+    replicate_prefix <- if(replicates > 1)
+      paste0(" R", formatC(seq_len(replicates), width = nchar(replicates), format = "d", flag = "0"))
+    else
+      ""
+
+    # Repeatedly render to XML format
+    xml <- lapply(replicate_prefix, function(prefix) {
+      rmarkdown::render(
+        input, output_format = "moodlequiz::moodlequiz_xml", output_options = list(replicate = prefix),
+        output_file = output, quiet = FALSE
+      )
+      xfun::read_utf8(output)
+    })
+
+    # Combine into a single XML for upload
+    xfun::write_utf8(
+      c(
+        '<?xml version="1.0" encoding="UTF-8"?>\n<quiz>',
+        do.call(c, xml),
+        '</quiz>'
+      ),
+      xfun::with_ext(input, "xml")
+    )
+
+    # Prevent knitting of document
+    render_env <- rlang::caller_env(n = 2)
+    rlang::env_poke(
+      render_env, nm = "requires_knit", value = FALSE,
+      inherit = TRUE, create = FALSE
+    )
+    # Change input to dummy md with Moodle XML import instructions
+    input <- system.file("instructions.md", package = "moodlequiz")
+    rlang::env_poke(
+      render_env, nm = "input", value = input,
+      inherit = TRUE, create = FALSE
     )
-    file.copy(output, xfun::with_ext(input, "xml"))
+    rlang::env_poke(
+      render_env, nm = "output_file", value = normalizePath(render_env$output_file),
+      inherit = TRUE, create = FALSE
+    )
+
+    input
   }
 
   # return format
@@ -39,7 +78,9 @@ moodlequiz <- function(replicates = 1L,
   )
 }
 
-moodlequiz_xml <- function(replicates = 1L,
+#' @keywords internal
+#' @export
+moodlequiz_xml <- function(replicate = "",
                            self_contained = TRUE,
                            extra_dependencies = NULL,
                            theme = NULL,
@@ -48,12 +89,20 @@ moodlequiz_xml <- function(replicates = 1L,
                            md_extensions = NULL,
                            pandoc_args = NULL,
                            ...) {
+  pre_processor <- function (metadata, input_file, ...) {
+    metadata$moodlequiz$replicate <- replicate
+    xfun::write_utf8(
+      c(
+        "---", yaml::as.yaml(metadata), "---",
+        split_rmd(input_file)$body
+      ),
+      input_file
+    )
+    list()
+  }
 
-  post_processor <- function(metadata, input_file, output_file, ...) {
+  post_processor <- function (metadata, input_file, output_file, ...) {
     # Convert content within pandoc divs to quiz questions
-    # xml <- xml2::read_xml(output_file)
-    # questions <- xml2::xml_find_all(xml, '//cdata')
-
     xml <- xfun::read_utf8(output_file)
     xml <- gsub("<cdata>", replacement = "<![CDATA[", xml, fixed = TRUE)
     xml <- gsub("</cdata>", replacement = "]]>", xml, fixed = TRUE)
@@ -71,6 +120,7 @@ moodlequiz_xml <- function(replicates = 1L,
   out <- output_format(
     knitr = knitr_options(),
     pandoc = pandoc_options(to = "html", ext = ".xml", lua_filters = filters),
+    pre_processor = pre_processor,
     post_processor = post_processor,
     base_format = bookdown::html_document2(
       highlight = NULL,

R/utils.R

@@ -17,7 +17,7 @@ split_rmd = function(file) {
       body = if (i[2] == n) {
         character()
       } else {
-        lapply(split(x, cut(seq_along(x), breaks = c(i[-1]-1, n))), `[`, -1L)
+        x[(i[2]+1):n]
       }
     )
   }

README.md

@@ -36,25 +36,28 @@ the x, y, color, and size are mapped randomly to one of the variables in
 the `mtcars` data.
 
     ---
-    output: moodlequiz::moodlequiz
+    output: 
+      moodlequiz::moodlequiz:
+        replicates: 5
     title: Drawing a scatterplot
     times: 5
-    category: datavis
+    moodlequiz:
+      category: datavis-scatterplots
     ---
 
-    ## Scatterplots
+    # Data
 
     ```{r setup, include = FALSE}
     library(tidyverse)
     library(rlang)
+    library(moodlequiz)
     knitr::opts_chunk$set(echo = FALSE,
                           results = "hide",
                           fig.height = 4, 
                           fig.width = 5,
                           fig.path = "",
                           fig.cap = "",
                           fig.align = "center")
-    library(moodlequiz)
     ```
 
     ```{r data}
@@ -73,6 +76,8 @@ the `mtcars` data.
     str(mtcars)
     ```
 
+    # Plot
+
     As a starting point, you decide to draw a scatter plot for some variables. Complete the code below to get the target plot below:
 
     ```r

inst/examples/draw-scatterplots.Rmd

@@ -1,14 +1,14 @@
 ---
-output: moodlequiz::moodlequiz
+output: 
+  moodlequiz::moodlequiz:
+    replicates: 5
 title: Drawing a scatterplot
 times: 5
 moodlequiz:
-  category: datavis
+  category: datavis-scatterplots
 ---
 
-# Scatterplots
-
-## Data
+# Data
 
 ```{r setup, include = FALSE}
 library(tidyverse)
@@ -39,7 +39,7 @@ You have been asked to analyse the `mtcars` data. The variables and the class ty
 str(mtcars)
 ```
 
-## Plot
+# Plot
 
 As a starting point, you decide to draw a scatter plot for some variables. Complete the code below to get the target plot below:
 

inst/header.lua

@@ -1,20 +1,13 @@
-local moodle_category = [[
-<question type="category">
-  <category>
-    <text>$course$/%s</text>
-  </category>
-</question>
-]]
-
 local base_category = nil
 local cloze_pattern = "{%d+:"
+local replicate_num = ""
 
 function process_header (elem)
   if (elem.classes[1] == "header" or elem.level > 2) then return elem end
-  elem.classes = {'question'}
+  elem.classes = {"question"}
   elem.attributes.name = pandoc.utils.stringify(elem.content[1])
   if (elem.level == 1) then
-    elem.attributes.type = 'category'
+    elem.attributes.type = "category"
     if (elem.attributes.category == nil) then
       elem.attributes.category = elem.identifier
     end
@@ -24,8 +17,9 @@ end
 
 
 function moodlequiz_meta(meta)
-  if (meta.moodlequiz ~= nil and meta.moodlequiz.category ~= nil) then
-    base_category = pandoc.utils.stringify(meta.moodlequiz.category)
+  if (meta.moodlequiz ~= nil) then
+    if (meta.moodlequiz.category ~= nil) then base_category = pandoc.utils.stringify(meta.moodlequiz.category) end
+    if (meta.moodlequiz.replicate ~= nil) then replicate_num = pandoc.utils.stringify(meta.moodlequiz.replicate) end
   end
 end
 
@@ -76,7 +70,7 @@ function header_questions(doc)
     end
   end
 
-  question_name_fmt = "Q%0" .. tostring(n_questions):len() .. "i: %s"
+  question_name_fmt = "Q%0" .. tostring(n_questions):len() .. "i%s: %s"
   question_num = 0
   for i,el in pairs(hblocks) do
     -- Look for cloze tags to set default question type 'description' or 'cloze'
@@ -99,7 +93,7 @@ function header_questions(doc)
     -- Add question number prefix for ordering
     if (el.attributes.type ~= "category") then
       question_num = question_num + 1
-      hblocks[i].attributes.name = question_name_fmt:format(question_num, el.attributes.name)
+      hblocks[i].attributes.name = question_name_fmt:format(question_num, replicate_num, el.attributes.name)
     end
   end
 

inst/instructions.md

@@ -0,0 +1,5 @@
+---
+title: Your quiz is ready!
+---
+
+Here's how to import the questions into Moodle.

inst/moodle.xml

@@ -1,6 +1 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<quiz>
-
 $body$
-
-</quiz>