R: Get information about the current tutorial

get_tutorial_info {learnr}

R Documentation

Get information about the current tutorial

Description

Returns information about the current tutorial. Ideally the function should be evaluated in a Shiny context, i.e. in a chunk with option context = "server". Note that the values of this function may change after the tutorial is completely initialized. If called in a non-reactive context, get_tutorial_info() will return default values that will most likely correspond to the current tutorial.

Usage

get_tutorial_info(
  tutorial_path = NULL,
  session = getDefaultReactiveDomain(),
  ...,
  encoding = "UTF-8"
)

Arguments

`tutorial_path`	Path to a tutorial `.Rmd` source file
`session`	The `session` object passed to function given to `shinyServer.` Default is `shiny::getDefaultReactiveDomain()`.
`...`	Arguments passed on to `rmarkdown::render` `output_format` The R Markdown output format to convert to. The option `"all"` will render all formats defined within the file. The option can be the name of a format (e.g. `"html_document"`) and that will render the document to that single format. One can also use a vector of format names to render to multiple formats. Alternatively, you can pass an output format object (e.g. `html_document()`). If using `NULL` then the output format is the first one defined in the YAML frontmatter in the input file (this defaults to HTML if no format is specified there). If you pass an output format object to `output_format`, the options specified in the YAML header or `_output.yml` will be ignored and you must explicitly set all the options you want when you construct the object. If you pass a string, the output format will use the output parameters in the YAML header or `_output.yml`. `output_dir` The output directory for the rendered `output_file`. This allows for a choice of an alternate directory to which the output file should be written (the default output directory of that of the input file). If a path is provided with a filename in `output_file` the directory specified here will take precedence. Please note that any directory path provided will create any necessary directories if they do not exist. `output_options` List of output options that can override the options specified in metadata (e.g. could be used to force `self_contained` or `mathjax = "local"`). Note that this is only valid when the output format is read from metadata (i.e. not a custom format object passed to `output_format`). `output_yaml` Paths to YAML files specifying output formats and their configurations. The first existing one is used. If none are found, then the function searches YAML files specified to the `output_yaml` top-level parameter in the YAML front matter, _output.yml or _output.yaml, and then uses the first existing one. `intermediates_dir` Intermediate files directory. If a path is specified then intermediate files will be written to that path. If `NULL`, intermediate files are written to the same directory as the input file. `knit_root_dir` The working directory in which to knit the document; uses knitr's `root.dir` knit option. If `NULL` then the behavior will follow the knitr default, which is to use the parent directory of the document. `runtime` The runtime target for rendering. The `static` option produces output intended for static files; `shiny` produces output suitable for use in a Shiny document (see `run`). The default, `auto`, allows the `runtime` target specified in the YAML metadata to take precedence, and renders for a `static` runtime target otherwise. `clean` Using `TRUE` will clean intermediate files that are created during rendering. `params` A list of named parameters that override custom params specified within the YAML front-matter (e.g. specifying a dataset to read or a date range to confine output to). Pass `"ask"` to start an application that helps guide parameter configuration. `knit_meta` (This option is reserved for expert use.) Metadata generated by knitr. `envir` The environment in which the code chunks are to be evaluated during knitting (can use `new.env()` to guarantee an empty new environment). `run_pandoc` An option for whether to run pandoc to convert Markdown output. `quiet` An option to suppress printing during rendering from knitr, pandoc command line and others. To only suppress printing of the last "Output created: " message, you can set `rmarkdown.render.message` to `FALSE`
`encoding`	Ignored. The encoding is always assumed to be UTF-8.

Value

Returns an ordinary list with the following elements:

tutorial_id: The ID of the tutorial, auto-generated or from the tutorial$id key in the tutorial's YAML front matter.
tutorial_version: The tutorial's version, auto-generated or from the tutorial$version key in the tutorial's YAML front matter.
items: A data frame with columns order, label, type and data describing the items (questions and exercises) in the tutorial. This item is only available in the running tutorial, not during the static pre-render step.
user_id: The current user.
learnr_version: The current version of the running learnr package.
language: The current language of the tutorial, either as chosen by the user or as specified in the language item of the YAML front matter.

Examples

if (rmarkdown::pandoc_available("1.4")) {
  tutorial_rmd <- local({
    # Use a temp copy of "Hello learnr" tutorial for this example
    src <- system.file(
      "tutorials", "hello", "hello.Rmd", package = "learnr"
    )
    dest <- tempfile(fileext = ".Rmd")
    file.copy(src, dest)
    dest
  })

  # ---- This is the example! ------------ #
  info <- get_tutorial_info(tutorial_rmd)
  # -------------------------------------- #

  # clean up the temporary Rmd used in this example
  unlink(tutorial_rmd)

  # This is the result of the example
  info
}