Add feature to parse text in the lesson definition.

DESCRIPTION

@@ -22,5 +22,6 @@ Imports:
     yaml,
     RCurl,
     digest,
-    tools
+    tools,
+    whisker
 Roxygen: list(wrap = FALSE)

NAMESPACE

@@ -45,3 +45,4 @@ importFrom(tools,file_ext)
 importFrom(tools,file_path_sans_ext)
 importFrom(yaml,yaml.load)
 importFrom(yaml,yaml.load_file)
+importFrom(whisker,whisker.render)

R/menu.R

@@ -293,6 +293,12 @@ loadLesson.default <- function(e, courseU, lesson){
   clearCustomTests()
   loadCustomTests(lesPath)
 
+  # Check if there is a localization file
+  localization <- file.path(lesPath, "locale.yaml") 
+  if(file.exists(localization)){
+  	dataName <- localize_lesson(localization, lesPath, shortname)
+  }
+
   # Attached class to content based on file extension
   class(dataName) <- get_content_class(dataName)
 

R/parse_content.R

@@ -54,4 +54,33 @@ parse_content.yaml <- function(file, e){
   lesson(df, lesson_name=meta$Lesson, course_name=meta$Course,
          author=meta$Author, type=meta$Type, organization=meta$Organization,
          version=meta$Version)
+}
+
+
+#' @importFrom tools file_ext
+#' @importFrom tools file_path_sans_ext
+#' @importFrom yaml yaml.load_file
+#' @importFrom whisker whisker.render
+localize_lesson <- function(file, lesPath, shortname){
+
+	# Load localization file
+	locale_yaml <- yaml.load_file(file)
+
+	# TO DO: Process localization. Placeholder loads first element.
+	locale_yaml <- locale_yaml[[1]]
+
+	# Load lesson file
+	lesson <- readLines(con = file.path(lesPath, shortname))
+
+	# Render localized lesson
+	lesson <- whisker.render(template = lesson, data = locale_yaml)
+
+	# Save localized lesson as a temporary file
+	file <- file_path_sans_ext(shortname)
+	extension <- paste0(".", file_ext(shortname))
+	localized_lesson <- tempfile(pattern = file, fileext = extension)
+	writeLines(lesson, con = localized_lesson)
+
+	# Return file path for localized lesson
+	return(localized_lesson)
 }