Introduction
This is a vignette that is designed for R package developers who are looking to understand how the data flows between the lesson source and the final website. I am assuming that the person reading this has familiarity with R packaging and R environments.
One of the design philosophies of The Workbench is that if a lesson author or contributor would like to add any sort of metadata or modify a setting in any given lesson, they can do so by editing the source of the lesson with no need to modify their workflow.
A note about the design
The design of this is very much PDD (panic-driven design). I was okay with wracking up technical debt because I knew that I could go back and refactor once I got it released. If I had a chance to go back and refactor, I would gladly do so. The creation of muliple storage objects using function factories was what I knew at the time. I now know that it might be better to use global environments instead. The implementation of this was originally done in pull request #248, which was trying to deduplicate code after the release of version 0.1.0, which was a massive push after finally getting the new website layout.
The flow of data I lay out here could all live in the same package-level environment (or even a package-level R6 object) instead of being implemented as function factories, but that’s a refactor for another day and another maintainer.
Two Sources of Metadata
Metadata is different from content because, while it is not directly related to the content, it has extra information that helps the users of the site navigate the content. For example, each episode page has three piece of metadata embedded as a YAML list at the top of the source file that defines the title along with estimated time for teaching and excercises.
In terms of the lesson itself, metadata that is related to the whole
lesson is stored in config.yaml
. This YAML file is designed
to be as flat as possible to avoid common problems with writing YAML.
Metadata here include things like the title of the Lesson, the source
page of the lesson, the time it was created, and the lesson program it
belongs to.
It also defines optional parameters such as the order of the episodes and other content that can be used to customise how the lesson is built.
The thing to know about this metdata and these variables is that they all get passed to {varnish} and are used to control how the lesson website is built along with the metadata.
An introduction to {varnish}
In order to understand how to pass data from config.yaml
to {varnish}, it is important to first understand the paradigm of how
{sandpaper} and {varnish} work together to produce a lesson website.
Behind the scenes, we build markdown with {knitr}, render the raw HTML
with Pandoc and then use {pkgdown} to insert the HTML and metadata into
a template (written in the logicless
templating language, Mustache) that can be updated and modified
independently of {sandpaper}. This template is called {varnish}.
In the paradigm of {pkgdown}, the HTML template is split up into different components that are rendered separately and then combined into a single layout template. For example, here is the template that defines the layout:
<!-- START: inst/pkgdown/templates/layout.html -->
<!-- Generated by pkgdown: do not edit by hand -->
<!doctype html>
<html lang="{{ lang }}" data-bs-theme="auto">
<head>
{{{ head }}}
</head>
<body>
{{{ header }}}
<div class="container">
<div class="row">
{{{ navbar }}}
{{{ content }}}
</div><!--/div.row-->
{{{ footer }}} {{! the end of div class container is in footer }}
</body>
</html>
<!-- END: inst/pkgdown/templates/layout.html-->
You can see that it contains {{{ head }}}
,
{{{ header }}}
, {{{ navbar }}}
,
{{{ content }}}
and {{{ footer }}}
. These are
all the results of the other rendered templates. For example, here’s the
head.html
template, which defines the content that goes in
the HTML <head>
tag (defining titles, metadata,
stylesheets, and JavaScript):
<meta charset="utf-8">
<title>{{#site}}{{&title}}{{/site}}{{#pagetitle}}: {{&pagetitle}}{{/pagetitle}}</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<script src="{{#site}}{{root}}{{/site}}assets/themetoggle.js"></script>
<link rel="stylesheet" type="text/css" href="{{#site}}{{root}}{{/site}}assets/styles.css">
<script src="{{#site}}{{root}}{{/site}}assets/scripts.js" type="text/javascript"></script>
<!-- mathjax -->
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
config: ["MMLorHTML.js"],
jax: ["input/TeX","input/MathML","output/HTML-CSS","output/NativeMML", "output/PreviewHTML"],
extensions: ["tex2jax.js","mml2jax.js","MathMenu.js","MathZoom.js", "fast-preview.js", "AssistiveMML.js", "a11y/accessibility-menu.js"],
TeX: {
extensions: ["AMSmath.js","AMSsymbols.js","noErrors.js","noUndefined.js"]
},
tex2jax: {
inlineMath: [['\\(', '\\)']],
displayMath: [ ['$$','$$'], ['\\[', '\\]'] ],
processEscapes: true
}
});
</script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js" integrity="sha256-nvJJv9wWKEm88qvoQl9ekL2J+k/RWIsaSScxxlsrv8k=" crossorigin="anonymous"></script>
<!-- Responsive Favicon for The Carpentries -->
<link rel="apple-touch-icon" sizes="180x180" href="{{#site}}{{root}}{{/site}}favicons/{{#yaml}}{{carpentry}}{{/yaml}}/apple-touch-icon.png">
<link rel="icon" type="image/png" sizes="32x32" href="{{#site}}{{root}}{{/site}}favicons/{{#yaml}}{{carpentry}}{{/yaml}}/favicon-32x32.png">
<link rel="icon" type="image/png" sizes="16x16" href="{{#site}}{{root}}{{/site}}favicons/{{#yaml}}{{carpentry}}{{/yaml}}/favicon-16x16.png">
<link rel="manifest" href="{{#site}}{{root}}{{/site}}favicons/{{#yaml}}{{carpentry}}{{/yaml}}/site.webmanifest">
<link rel="mask-icon" href="{{#site}}{{root}}{{/site}}favicons/{{#yaml}}{{carpentry}}{{/yaml}}/safari-pinned-tab.svg" color="#5bbad5">
<meta name="msapplication-TileColor" content="#da532c">
<meta name="theme-color" media="(prefers-color-scheme: light)" content="white" />
<meta name="theme-color" media="(prefers-color-scheme: dark)" content="black" />
The templates used by {varnish} will take metadata from one of two sources:
- a
_pkgdown.yaml
file that defines global metadata like language (see the pkgdown metadata section for details. - a list of values passed to the
pkgdown::render_page()
function. These values can be both global and local.
These get inserted into the template via the
pkgdown::render_page()
function where the contents of the
_pkgdown.yaml
file are inserted into the data list as
$yaml
.
The challenge for {sandpaper} is this: when we have a list of
per-lesson global variables that need to be allocated when
build_lesson()
is run and per-file variables that need to
be allocated before every call to build_html()
.
The solution that we’ve come up with is to store these lists in environments that are encapsulated by function factories, which are detailed in the next section.
Storage Function Factories
There are two types of storage function
factories in {sandpaper}: Lesson Store
(.lesson_store()
) and List Store
(.list_store()
). Both of these return lists of functions
that access their calling environments, which are created when the
package is loaded:
List Store
The list store acts like a persistent list that has
get()
set()
, clear()
,
copy()
and update()
methods.
snd <- asNamespace("sandpaper")
this_list <- snd$.list_store()
names(this_list)
## [1] "get" "update" "set" "clear" "copy"
class(this_list)
## [1] "list-store"
# to set a list, use a NULL key
this_list$set(key = NULL, list(
A = list(first = 1),
B = list(
C = list(
D = letters[1:4],
E = sqrt(2),
F = TRUE
),
G = head(sleep)
)
))
# get the list
this_list$get()
## $A
## $A$first
## [1] 1
##
##
## $B
## $B$C
## $B$C$D
## [1] "a" "b" "c" "d"
##
## $B$C$E
## [1] 1.414214
##
## $B$C$F
## [1] TRUE
##
##
## $B$G
## extra group ID
## 1 0.7 1 1
## 2 -1.6 1 2
## 3 -0.2 1 3
## 4 -1.2 1 4
## 5 -0.1 1 5
## 6 3.4 1 6
# copy a list so that you can preserve the original list
that_list <- this_list$copy()
# update list elements by adding to them (note: vectors will be replaced)
that_list$update(list(A = list(platform = "MY COMPUTER")))
that_list$get()
## $A
## $A$first
## [1] 1
##
## $A$platform
## [1] "MY COMPUTER"
##
##
## $B
## $B$C
## $B$C$D
## [1] "a" "b" "c" "d"
##
## $B$C$E
## [1] 1.414214
##
## $B$C$F
## [1] TRUE
##
##
## $B$G
## extra group ID
## 1 0.7 1 1
## 2 -1.6 1 2
## 3 -0.2 1 3
## 4 -1.2 1 4
## 5 -0.1 1 5
## 6 3.4 1 6
# set nested list elements
that_list$set(c("A", "platform"), "YOUR COMPUTER")
# note that modified copies do not modify the originals
that_list$get()[["A"]]
## $first
## [1] 1
##
## $platform
## [1] "YOUR COMPUTER"
this_list$get()[["A"]]
## $first
## [1] 1
Lesson Store
This creates the object containing the pegboard::Lesson
object, that we can use to extract episode-specific metadata along with
the text of the questions. It is a special object because when a lesson
is set with this object, it will additionally set the other
global data.
When {sandpaper} is loaded, the List Store and Lesson Store objects are created and live in the {sandpaper} namespace as long as the session is active.
snd <- asNamespace("sandpaper")
some_lesson <- snd$.lesson_store()
names(some_lesson)
## [1] "get" "valid" "set" "clear"
Example
All of these metadata are collected and stored in memory before the
lesson is built (triggered during validate_lesson()
), which
are accessible via the objects defined by the internal
sandpaper:::set_globals()
. Here I will set up an example
lesson that I will use to demonstrate these global variables. Please
note that I will be using internal functions in this demonstration.
These internal functions are not guaranteed to be stable outside of the
context of {sandpaper}. Using the asNamespace("sandpaper")
function allows me to create a method for accessing the internal
functions:
library("sandpaper")
snd <- asNamespace("sandpaper")
# create a new lesson
lsn <- create_lesson(tempfile(), name = "An Example Lesson",
rstudio = TRUE, open = FALSE, rmd = FALSE)
# add a new episode
create_episode_md(title = "First Example", add = TRUE, path = lsn, open = FALSE)
## /tmp/RtmpercEqO/file2b422c29612b/episodes/first-example.md
Within {sandpaper}, there are environments that contain metadata
related to the whole lesson called .store
,
.resources
, instructor_globals
,
learner_globals
, and this_metadata
. Before the
lesson is validated, these values are empty:
snd <- asNamespace("sandpaper")
class(snd$.store)
## [1] "list"
print(snd$.store$get())
## NULL
class(snd$this_metadata)
## [1] "list-store"
snd$this_metadata$get()
## list()
class(snd$.resources)
## [1] "list-store"
snd$.resources$get()
## list()
class(snd$instructor_globals)
## [1] "list-store"
snd$instructor_globals$get()
## list()
class(snd$learner_globals)
## [1] "list-store"
snd$learner_globals$get()
## list()
These will contain the following information:
-
.store
apegboard::Lesson
object that contains the XML representation of the parsed Markdown source files -
this_metadata
the real and computed metadata associated with the lesson along with the JSON-LD template for generating the metadata in the footer of the lesson. -
.resources
a list of the availabe files used to build the lesson in the order specified byconfig.yaml
-
instructor_globals
pre-computed global data that includes the sidebar template, the syllabus, the dropdown menus, and information about the packages used to build the lesson -
learner_globals
same asinstructor_globals
, but specifically for learner view
When I run validate_lesson()
the first time, all the
metadata is collected and parsed from the config.yaml
, and
the individual episodes and cached.
# first run is always longer than the second
system.time(validate_lesson(lsn))
## ── Validating Fenced Divs ──────────────────────────────────────────────
## ── Validating Internal Links and Images ────────────────────────────────
## user system elapsed
## 0.340 0.012 0.351
system.time(validate_lesson(lsn))
## ── Validating Fenced Divs ──────────────────────────────────────────────
## ── Validating Internal Links and Images ────────────────────────────────
## user system elapsed
## 0.100 0.008 0.108
The validate_lesson()
call will pull from the cache in
.store
if it exists and is valid (which means that nothing
in git has changed). If it’s not valid or does not exist, then all of
the global storage is initialised in this general cascade:
## validate_lesson()
## └─this_lesson()
## ├─.store$valid()
## │ ├─gert::git_diff()
## │ ├─gert::git_status()
## │ └─gert::git_log()
## ├─pegboard::Lesson$new()
## └─.store$set()
## └─set_globals()
## ├─initialise_metadata()
## │ ├─get_config()
## │ ├─template_metadata()
## │ └─this_metadata$set()
## ├─set_language()
## │ └─add_varnish_translations()
## │ └─tr_()
## │ └─these$translations
## ├─set_resource_list()
## │ ├─get_resource_list()
## │ │ └─get_config()
## │ └─.resources$set()
## ├─create_sidebar()
## ├─create_resources_dropdown()
## ├─learner_globals$set()
## └─instructor_globals$set()
Now when we these variables are called, you can see the information stored in them.
Lesson Storage
This function stores the pegboard::Lesson
object and is
responsible for initialising and resetting the variable cache.
snd <- asNamespace("sandpaper")
class(snd$.store)
## [1] "list"
print(snd$.store$get())
## <Lesson>
## Public:
## blocks: function (type = NULL, level = 0, path = FALSE)
## built: NULL
## challenges: function (path = FALSE, graph = FALSE, recurse = TRUE)
## children: NULL
## clone: function (deep = FALSE)
## episodes: list
## extra: list
## files: active binding
## get: function (element = NULL, collection = "episodes")
## handout: function (path = NULL, solution = FALSE)
## has_children: active binding
## initialize: function (path = ".", rmd = FALSE, jekyll = TRUE, ...)
## isolate_blocks: function ()
## load_built: function ()
## n_problems: active binding
## overview: FALSE
## path: /tmp/RtmpercEqO/file2b422c29612b
## reset: function ()
## rmd: FALSE
## sandpaper: TRUE
## show_problems: active binding
## solutions: function (path = FALSE)
## summary: function (collection = "episodes")
## thin: function (verbose = TRUE)
## trace_lineage: function (episode_path)
## validate_divs: function ()
## validate_headings: function (verbose = TRUE)
## validate_links: function ()
## Private:
## deep_clone: function (name, value)
We can check if the cache needs to be reset by using the
$valid()
function inside this object, which checks the git
log, git status, and git diff as a global check of the lesson contents.
When nothing changes, it returns TRUE:
snd$.store$valid(lsn)
## [1] TRUE
However, if we update the lesson contents in some way by setting a
config variable, it will be FALSE
, indicating that it needs
to be reset:
set_config(c(handout = TRUE), path = lsn, write = TRUE, create = TRUE)
## ℹ Writing to /tmp/RtmpercEqO/file2b422c29612b/config.yaml
## → NA -> handout: true
snd$.store$valid(lsn)
## [1] FALSE
snd$.store$set(lsn)
snd$.store$valid(lsn)
## [1] TRUE
Metadata
The metadata is used to store the content of config.yaml
and to provide computed metadata for a lesson that is included in the
footer as a JSON-LD object, which is useful for indexing. Note that this
metadata must be duplicated for each page to give the correct URL and
identifiers.
snd <- asNamespace("sandpaper")
snd$this_metadata$get()
## $carpentry
## [1] "incubator"
##
## $title
## [1] "An Example Lesson"
##
## $created
## [1] "2024-11-07"
##
## $keywords
## [1] "software, data, lesson, The Carpentries"
##
## $life_cycle
## [1] "pre-alpha"
##
## $license
## [1] "CC-BY 4.0"
##
## $source
## [1] "https://github.com/carpentries/file2b422c29612b"
##
## $branch
## [1] "main"
##
## $contact
## [1] "team@carpentries.org"
##
## $episodes
## [1] "introduction.md" "first-example.md"
##
## $metadata_template
## [1] "{{=<% %>=}}"
## [2] "{"
## [3] " \"@context\": \"https://schema.org\","
## [4] " \"@type\": \"TrainingMaterial\","
## [5] " \"@id\": \"<% url %>\","
## [6] " \"inLanguage\": \"<% lang %>\","
## [7] " \"dct:conformsTo\": \"https://bioschemas.org/profiles/TrainingMaterial/1.0-RELEASE\","
## [8] " \"description\": \"<% desc %><% ^desc %>A Carpentries Lesson teaching foundational data and coding skills to researchers worldwide<% /desc %>\","
## [9] " \"keywords\": \"<% keywords %><% ^keywords %>software,data,lesson,The Carpentries<% /keywords %>\","
## [10] " \"name\": \"<% &pagetitle %>\","
## [11] " \"creativeWorkStatus\": \"active\","
## [12] " \"url\": \"<% url %>\","
## [13] " \"identifier\": \"<% url %>\","
## [14] " <% #date %>\"dateCreated\": \"<% created %>\","
## [15] " \"dateModified\": \"<% modified %>\","
## [16] " \"datePublished\": \"<% published %>\"<% /date %>"
## [17] "}"
## [18] "<%={{ }}=%>"
##
## $pagetitle
## [1] "An Example Lesson"
##
## $date
## $date$created
## [1] "2024-11-07"
##
## $date$modified
## [1] "2024-11-07"
##
## $date$published
## [1] "2024-11-07"
##
##
## $url
## [1] "https://carpentries.github.io/file2b422c29612b/"
##
## $citation
## [1] "CITATION.cff"
##
## $overview
## [1] FALSE
##
## $handout
## [1] TRUE
This metadata is rendered as JSON-LD and passed as a new variable to
{varnish} using the internal fill_metadata_template()
function:
writeLines(snd$fill_metadata_template(snd$this_metadata))
## {
## "@context": "https://schema.org",
## "@type": "TrainingMaterial",
## "@id": "https://carpentries.github.io/file2b422c29612b/index.html",
## "inLanguage": "en",
## "dct:conformsTo": "https://bioschemas.org/profiles/TrainingMaterial/1.0-RELEASE",
## "description": "A Carpentries Lesson teaching foundational data and coding skills to researchers worldwide",
## "keywords": "software, data, lesson, The Carpentries",
## "name": "An Example Lesson",
## "creativeWorkStatus": "active",
## "url": "https://carpentries.github.io/file2b422c29612b/index.html",
## "identifier": "https://carpentries.github.io/file2b422c29612b/index.html",
## "dateCreated": "2024-11-07",
## "dateModified": "2024-11-07",
## "datePublished": "2024-11-07"
## }
Lesson Resources (files)
The next thing that we store globally are the resources we use to build the lesson. This allows us to avoid needing to constantly read the file system:
snd <- asNamespace("sandpaper")
snd$.resources$get()
## $.
## /tmp/RtmpercEqO/file2b422c29612b/CODE_OF_CONDUCT.md
## "/tmp/RtmpercEqO/file2b422c29612b/CODE_OF_CONDUCT.md"
## /tmp/RtmpercEqO/file2b422c29612b/LICENSE.md
## "/tmp/RtmpercEqO/file2b422c29612b/LICENSE.md"
## /tmp/RtmpercEqO/file2b422c29612b/config.yaml
## "/tmp/RtmpercEqO/file2b422c29612b/config.yaml"
## /tmp/RtmpercEqO/file2b422c29612b/index.md
## "/tmp/RtmpercEqO/file2b422c29612b/index.md"
## /tmp/RtmpercEqO/file2b422c29612b/links.md
## "/tmp/RtmpercEqO/file2b422c29612b/links.md"
##
## $episodes
## /tmp/RtmpercEqO/file2b422c29612b/episodes/introduction.md
## "/tmp/RtmpercEqO/file2b422c29612b/episodes/introduction.md"
## /tmp/RtmpercEqO/file2b422c29612b/episodes/first-example.md
## "/tmp/RtmpercEqO/file2b422c29612b/episodes/first-example.md"
##
## $instructors
## /tmp/RtmpercEqO/file2b422c29612b/instructors/instructor-notes.md
## "/tmp/RtmpercEqO/file2b422c29612b/instructors/instructor-notes.md"
##
## $learners
## /tmp/RtmpercEqO/file2b422c29612b/learners/reference.md
## "/tmp/RtmpercEqO/file2b422c29612b/learners/reference.md"
## /tmp/RtmpercEqO/file2b422c29612b/learners/setup.md
## "/tmp/RtmpercEqO/file2b422c29612b/learners/setup.md"
##
## $profiles
## /tmp/RtmpercEqO/file2b422c29612b/profiles/learner-profiles.md
## "/tmp/RtmpercEqO/file2b422c29612b/profiles/learner-profiles.md"
##
## $`renv/profiles/lesson-requirements`
##
## "/tmp/RtmpercEqO/file2b422c29612b/renv/profiles/lesson-requirements/renv.lock"
Global and Local Variables
The rest are global and local variables that are recorded in the
instructor_globals
and learner_globals
. These
are copied for each page and updated with local data (e.g. the sidebar
needs to include headings for the current page).
snd <- asNamespace("sandpaper")
snd$instructor_globals$get()
## $aio
## [1] TRUE
##
## $instructor
## [1] TRUE
##
## $sidebar
## [1] "<div class=\"accordion accordion-flush\" id=\"accordionFlush1\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading1\">\n <a href=\"index.html\">Summary and Schedule</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
## [2] "<div class=\"accordion accordion-flush\" id=\"accordionFlush2\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading2\">\n <a href='introduction.html'>1. introduction</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
## [3] "<div class=\"accordion accordion-flush\" id=\"accordionFlush3\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading3\">\n <a href='first-example.html'>2. First Example</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
##
## $more
## [1] "<hr><li><a class='dropdown-item' href='reference.html'>Reference</a></li>"
##
## $resources
## [1] "<hr><li><a class='dropdown-item' href='reference.html'>Reference</a></li>"
##
## $translate
## $translate$SkipToMain
## [1] "Skip to main content"
##
## $translate$iPreAlpha
## [1] "Pre-Alpha"
##
## $translate$PreAlphaNote
## [1] "This lesson is in the pre-alpha phase, which means that it is in early development, but has not yet been taught."
##
## $translate$AlphaNote
## [1] "This lesson is in the alpha phase, which means that it has been taught once and lesson authors are iterating on feedback."
##
## $translate$iAlpha
## [1] "Alpha"
##
## $translate$BetaNote
## [1] "This lesson is in the beta phase, which means that it is ready for teaching by instructors outside of the original author team."
##
## $translate$iBeta
## [1] "Beta"
##
## $translate$PeerReview
## [1] "This lesson has passed peer review."
##
## $translate$InstructorView
## [1] "Instructor View"
##
## $translate$LearnerView
## [1] "Learner View"
##
## $translate$MainNavigation
## [1] "Main Navigation"
##
## $translate$ToggleNavigation
## [1] "Toggle Navigation"
##
## $translate$ToggleDarkMode
## [1] "Toggle theme (auto)"
##
## $translate$Menu
## [1] "Menu"
##
## $translate$SearchButton
## [1] "Search the All In One page"
##
## $translate$Setup
## [1] "Setup"
##
## $translate$KeyPoints
## [1] "Key Points"
##
## $translate$InstructorNotes
## [1] "Instructor Notes"
##
## $translate$Glossary
## [1] "Glossary"
##
## $translate$LearnerProfiles
## [1] "Learner Profiles"
##
## $translate$More
## [1] "More"
##
## $translate$LessonProgress
## [1] "Lesson Progress"
##
## $translate$CloseMenu
## [1] "close menu"
##
## $translate$EPISODES
## [1] "EPISODES"
##
## $translate$Home
## [1] "Home"
##
## $translate$HomePageNav
## [1] "Home Page Navigation"
##
## $translate$RESOURCES
## [1] "RESOURCES"
##
## $translate$ExtractAllImages
## [1] "Extract All Images"
##
## $translate$AIO
## [1] "See all in one page"
##
## $translate$DownloadHandout
## [1] "Download Lesson Handout"
##
## $translate$ExportSlides
## [1] "Export Chapter Slides"
##
## $translate$PreviousAndNext
## [1] "Previous and Next Chapter"
##
## $translate$Previous
## [1] "Previous"
##
## $translate$EstimatedTime
## [1] "Estimated time: {icons$clock} {minutes} minutes"
##
## $translate$Next
## [1] "Next"
##
## $translate$NextChapter
## [1] "Next Chapter"
##
## $translate$LastUpdate
## [1] "Last updated on {updated}"
##
## $translate$EditThisPage
## [1] "Edit this page"
##
## $translate$ExpandAllSolutions
## [1] "Expand All Solutions"
##
## $translate$SetupInstructions
## [1] "Setup Instructions"
##
## $translate$DownloadFiles
## [1] "Download files required for the lesson"
##
## $translate$ActualScheduleNote
## [1] "The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor."
##
## $translate$BackToTop
## [1] "Back To Top"
##
## $translate$SpanToTop
## [1] "<(Back)> To Top"
##
## $translate$ThisLessonCoC
## [1] "This lesson is subject to the <(Code of Conduct)>"
##
## $translate$CoC
## [1] "Code of Conduct"
##
## $translate$EditOnGH
## [1] "Edit on GitHub"
##
## $translate$Contributing
## [1] "Contributing"
##
## $translate$Source
## [1] "Source"
##
## $translate$Cite
## [1] "Cite"
##
## $translate$Contact
## [1] "Contact"
##
## $translate$About
## [1] "About"
##
## $translate$MaterialsLicensedUnder
## [1] "Materials licensed under {license} by the authors"
##
## $translate$TemplateLicense
## [1] "Template licensed under <(CC-BY 4.0)> by {template_authors}"
##
## $translate$Carpentries
## [1] "The Carpentries"
##
## $translate$BuiltWith
## [1] "Built with {sandpaper_link}, {pegboard_link}, and {varnish_link}"
##
## $translate$ExpandAllSolutions
## [1] "Expand All Solutions"
##
## $translate$CollapseAllSolutions
## [1] "Collapse All Solutions"
##
## $translate$Collapse
## [1] "Collapse"
##
## $translate$Episodes
## [1] "Episodes"
##
## $translate$GiveFeedback
## [1] "Give Feedback"
##
## $translate$LearnMore
## [1] "Learn More"
##
##
## $sandpaper_version
## (0.16.10.9000)
##
## $sandpaper_cfg
## NULL
##
## $pegboard_version
## (0.7.7.9000)
##
## $pegboard_cfg
## [1] "carpentries/pegboard/tree/fd1d354dee45f8398b365c1ee93d52d283172e84"
##
## $varnish_version
## (1.0.5.9000)
##
## $varnish_cfg
## [1] "carpentries/varnish/tree/eb621a78c21cf2d0584f08683ca4a3447f85efca"
##
## $sandpaper_link
## <a href="https://github.com/carpentries/sandpaper">sandpaper (0.16.10.9000)</a>
##
## $pegboard_link
## <a href="https://github.com/carpentries/pegboard/tree/fd1d354dee45f8398b365c1ee93d52d283172e84">pegboard (0.7.7.9000)</a>
##
## $varnish_link
## <a href="https://github.com/carpentries/varnish/tree/eb621a78c21cf2d0584f08683ca4a3447f85efca">varnish (1.0.5.9000)</a>
##
## $syllabus
## episode timings path percents
## introduction.md introduction 00h 00m introduction.html 0
## first-example.md First Example 00h 12m first-example.html 50
## Finish 00h 24m 100
## questions
## introduction.md How do you write a lesson using R Markdown and `{sandpaper}`?
## first-example.md How do you write a lesson using R Markdown and `{sandpaper}`?
##
##
## $overview
## [1] FALSE
snd$learner_globals$get()
## $aio
## [1] TRUE
##
## $instructor
## [1] FALSE
##
## $sidebar
## [1] "<div class=\"accordion accordion-flush\" id=\"accordionFlush1\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading1\">\n <a href=\"index.html\">Summary and Setup</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
## [2] "<div class=\"accordion accordion-flush\" id=\"accordionFlush2\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading2\">\n <a href='introduction.html'>1. introduction</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
## [3] "<div class=\"accordion accordion-flush\" id=\"accordionFlush3\">\n <div class=\"accordion-item\">\n <div class=\"accordion-header\" id=\"flush-heading3\">\n <a href='first-example.html'>2. First Example</a>\n </div><!--/div.accordion-header-->\n \n </div><!--/div.accordion-item-->\n</div><!--/div.accordion-flush-->\n"
##
## $more
## [1] "<li><a class='dropdown-item' href='reference.html'>Reference</a></li>"
##
## $resources
## [1] "<li><a href='reference.html'>Reference</a></li>"
##
## $translate
## $translate$SkipToMain
## [1] "Skip to main content"
##
## $translate$iPreAlpha
## [1] "Pre-Alpha"
##
## $translate$PreAlphaNote
## [1] "This lesson is in the pre-alpha phase, which means that it is in early development, but has not yet been taught."
##
## $translate$AlphaNote
## [1] "This lesson is in the alpha phase, which means that it has been taught once and lesson authors are iterating on feedback."
##
## $translate$iAlpha
## [1] "Alpha"
##
## $translate$BetaNote
## [1] "This lesson is in the beta phase, which means that it is ready for teaching by instructors outside of the original author team."
##
## $translate$iBeta
## [1] "Beta"
##
## $translate$PeerReview
## [1] "This lesson has passed peer review."
##
## $translate$InstructorView
## [1] "Instructor View"
##
## $translate$LearnerView
## [1] "Learner View"
##
## $translate$MainNavigation
## [1] "Main Navigation"
##
## $translate$ToggleNavigation
## [1] "Toggle Navigation"
##
## $translate$ToggleDarkMode
## [1] "Toggle theme (auto)"
##
## $translate$Menu
## [1] "Menu"
##
## $translate$SearchButton
## [1] "Search the All In One page"
##
## $translate$Setup
## [1] "Setup"
##
## $translate$KeyPoints
## [1] "Key Points"
##
## $translate$InstructorNotes
## [1] "Instructor Notes"
##
## $translate$Glossary
## [1] "Glossary"
##
## $translate$LearnerProfiles
## [1] "Learner Profiles"
##
## $translate$More
## [1] "More"
##
## $translate$LessonProgress
## [1] "Lesson Progress"
##
## $translate$CloseMenu
## [1] "close menu"
##
## $translate$EPISODES
## [1] "EPISODES"
##
## $translate$Home
## [1] "Home"
##
## $translate$HomePageNav
## [1] "Home Page Navigation"
##
## $translate$RESOURCES
## [1] "RESOURCES"
##
## $translate$ExtractAllImages
## [1] "Extract All Images"
##
## $translate$AIO
## [1] "See all in one page"
##
## $translate$DownloadHandout
## [1] "Download Lesson Handout"
##
## $translate$ExportSlides
## [1] "Export Chapter Slides"
##
## $translate$PreviousAndNext
## [1] "Previous and Next Chapter"
##
## $translate$Previous
## [1] "Previous"
##
## $translate$EstimatedTime
## [1] "Estimated time: {icons$clock} {minutes} minutes"
##
## $translate$Next
## [1] "Next"
##
## $translate$NextChapter
## [1] "Next Chapter"
##
## $translate$LastUpdate
## [1] "Last updated on {updated}"
##
## $translate$EditThisPage
## [1] "Edit this page"
##
## $translate$ExpandAllSolutions
## [1] "Expand All Solutions"
##
## $translate$SetupInstructions
## [1] "Setup Instructions"
##
## $translate$DownloadFiles
## [1] "Download files required for the lesson"
##
## $translate$ActualScheduleNote
## [1] "The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor."
##
## $translate$BackToTop
## [1] "Back To Top"
##
## $translate$SpanToTop
## [1] "<(Back)> To Top"
##
## $translate$ThisLessonCoC
## [1] "This lesson is subject to the <(Code of Conduct)>"
##
## $translate$CoC
## [1] "Code of Conduct"
##
## $translate$EditOnGH
## [1] "Edit on GitHub"
##
## $translate$Contributing
## [1] "Contributing"
##
## $translate$Source
## [1] "Source"
##
## $translate$Cite
## [1] "Cite"
##
## $translate$Contact
## [1] "Contact"
##
## $translate$About
## [1] "About"
##
## $translate$MaterialsLicensedUnder
## [1] "Materials licensed under {license} by the authors"
##
## $translate$TemplateLicense
## [1] "Template licensed under <(CC-BY 4.0)> by {template_authors}"
##
## $translate$Carpentries
## [1] "The Carpentries"
##
## $translate$BuiltWith
## [1] "Built with {sandpaper_link}, {pegboard_link}, and {varnish_link}"
##
## $translate$ExpandAllSolutions
## [1] "Expand All Solutions"
##
## $translate$CollapseAllSolutions
## [1] "Collapse All Solutions"
##
## $translate$Collapse
## [1] "Collapse"
##
## $translate$Episodes
## [1] "Episodes"
##
## $translate$GiveFeedback
## [1] "Give Feedback"
##
## $translate$LearnMore
## [1] "Learn More"
##
##
## $sandpaper_version
## (0.16.10.9000)
##
## $sandpaper_cfg
## NULL
##
## $pegboard_version
## (0.7.7.9000)
##
## $pegboard_cfg
## [1] "carpentries/pegboard/tree/fd1d354dee45f8398b365c1ee93d52d283172e84"
##
## $varnish_version
## (1.0.5.9000)
##
## $varnish_cfg
## [1] "carpentries/varnish/tree/eb621a78c21cf2d0584f08683ca4a3447f85efca"
##
## $sandpaper_link
## <a href="https://github.com/carpentries/sandpaper">sandpaper (0.16.10.9000)</a>
##
## $pegboard_link
## <a href="https://github.com/carpentries/pegboard/tree/fd1d354dee45f8398b365c1ee93d52d283172e84">pegboard (0.7.7.9000)</a>
##
## $varnish_link
## <a href="https://github.com/carpentries/varnish/tree/eb621a78c21cf2d0584f08683ca4a3447f85efca">varnish (1.0.5.9000)</a>
##
## $overview
## [1] FALSE
Translations
In the majority of the {varnish} templates are keys that need
translations that are in the format of
{{ translate.ThingInPascalCase }}
:
<!-- START: inst/pkgdown/templates/content-syllabus.html -->
<div class="col-xl-12 col-lg-12">
<main id="main-content" class="main-content">
<h1>{{& pagetitle }}</h1>
<div class="container lesson-content">
<p>
{{# translate.LastUpdate }} {{& translate.LastUpdate }} |{{/ translate.LastUpdate }}
<a href="{{#yaml}}{{source}}/edit/{{branch}}/{{/yaml}}{{file_source}}{{^file_source}}index.md{{/file_source}}">
{{ translate.EditThisPage }} <i aria-hidden="true" data-feather="edit"></i>
</a>
</p>
{{& readme }}
{{#syllabus}}
<section id="schedule">
<table class="table schedule table-striped" role="presentation">
<tbody>
{{#setup}}
<tr>
<td></td><td><a href="#setup">{{ translate.SetupInstructions }}</a></td><td> {{ translate.DownloadFiles }}</td>
</tr>
{{/setup}}
{{& syllabus }}
</table>
<p>
{{ translate.ActualScheduleNote }}
</p>
</section>
{{/syllabus}}
{{#setup}}
<section id="setup">
{{{setup}}}
</section>
{{/setup}}
</main>
</div>
<!-- END : inst/pkgdown/templates/content-syllabus.html -->
These variables are in {sandpaper} and are expected to
exist. Because they are expected to exist, theese variables are
generated and stored in the internal environment
these$translations
by the function
establish_translation_vars()
when the package is loaded.
When the lesson is validated, these variables are translated to the
correct language with set_language()
and placed in the
instructor_globals
and learner_globals
storage. These variables are passed directly to {varnish} templates,
which eventually get processed by {whisker}:
snd <- asNamespace("sandpaper")
whisker::whisker.render("Edit this page: {{ translate.EditThisPage }}",
data = snd$instructor_globals$get()
)
## [1] "Edit this page: Edit this page"
This is key to building lessons in other languages, regardless of
your default language. The lesson author sets the lang:
config key to the two-letter language code that the lesson is written
in. This gets passed to the set_language()
function, which
modifies the translations inside the global data, but it does not modify
the language of the user session:
snd <- asNamespace("sandpaper")
snd$set_config(c(lang = "es"), path = lsn, create = TRUE, write = TRUE)
## ℹ Writing to /tmp/RtmpercEqO/file2b422c29612b/config.yaml
## → NA -> lang: 'es'
snd$this_lesson(lsn)
whisker::whisker.render("Edit this page: {{ translate.EditThisPage }}",
data = snd$instructor_globals$get()
)
## [1] "Edit this page: Mejora esta página"
Sys.getenv("LANGUAGE")
## [1] "en"
Switching the language is controlled entirely from within the lesson config:
snd$set_config(c(lang = "en"), path = lsn, create = TRUE, write = TRUE)
## ℹ Writing to /tmp/RtmpercEqO/file2b422c29612b/config.yaml
## → lang: 'es' -> lang: 'en'
snd$this_lesson(lsn)
whisker::whisker.render("Edit this page: {{ translate.EditThisPage }}",
data = snd$instructor_globals$get()
)
## [1] "Edit this page: Edit this page"
Translation Variables
There are 62 translations generated by set_language()
that correspond to the following variables in
varnish:
variable | string |
---|---|
translate.SkipToMain |
'Skip to main content' |
translate.iPreAlpha |
'Pre-Alpha' |
translate.PreAlphaNote |
'This lesson is in the pre-alpha phase, which means that it is in early development, but has not yet been taught.' |
translate.AlphaNote |
'This lesson is in the alpha phase, which means that it has been taught once and lesson authors are iterating on feedback.' |
translate.iAlpha |
'Alpha' |
translate.BetaNote |
'This lesson is in the beta phase, which means that it is ready for teaching by instructors outside of the original author team.' |
translate.iBeta |
'Beta' |
translate.PeerReview |
'This lesson has passed peer review.' |
translate.InstructorView |
'Instructor View' |
translate.LearnerView |
'Learner View' |
translate.MainNavigation |
'Main Navigation' |
translate.ToggleNavigation |
'Toggle Navigation' |
translate.ToggleDarkMode |
'Toggle theme (auto)' |
translate.Menu |
'Menu' |
translate.SearchButton |
'Search the All In One page' |
translate.Setup |
'Setup' |
translate.KeyPoints |
'Key Points' |
translate.InstructorNotes |
'Instructor Notes' |
translate.Glossary |
'Glossary' |
translate.LearnerProfiles |
'Learner Profiles' |
translate.More |
'More' |
translate.LessonProgress |
'Lesson Progress' |
translate.CloseMenu |
'close menu' |
translate.EPISODES |
'EPISODES' |
translate.Home |
'Home' |
translate.HomePageNav |
'Home Page Navigation' |
translate.RESOURCES |
'RESOURCES' |
translate.ExtractAllImages |
'Extract All Images' |
translate.AIO |
'See all in one page' |
translate.DownloadHandout |
'Download Lesson Handout' |
translate.ExportSlides |
'Export Chapter Slides' |
translate.PreviousAndNext |
'Previous and Next Chapter' |
translate.Previous |
'Previous' |
translate.EstimatedTime |
'Estimated time: {icons$clock} {minutes} minutes' |
translate.Next |
'Next' |
translate.NextChapter |
'Next Chapter' |
translate.LastUpdate |
'Last updated on {updated}' |
translate.EditThisPage |
'Edit this page' |
translate.ExpandAllSolutions |
'Expand All Solutions' |
translate.SetupInstructions |
'Setup Instructions' |
translate.DownloadFiles |
'Download files required for the lesson' |
translate.ActualScheduleNote |
'The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor.' |
translate.BackToTop |
'Back To Top' |
translate.SpanToTop |
'<(Back)> To Top' |
translate.ThisLessonCoC |
'This lesson is subject to the <(Code of Conduct)>' |
translate.CoC |
'Code of Conduct' |
translate.EditOnGH |
'Edit on GitHub' |
translate.Contributing |
'Contributing' |
translate.Source |
'Source' |
translate.Cite |
'Cite' |
translate.Contact |
'Contact' |
translate.About |
'About' |
translate.MaterialsLicensedUnder |
'Materials licensed under {license} by the authors' |
translate.TemplateLicense |
'Template licensed under <(CC-BY 4.0)> by {template_authors}' |
translate.Carpentries |
'The Carpentries' |
translate.BuiltWith |
'Built with {sandpaper_link}, {pegboard_link}, and {varnish_link}' |
translate.ExpandAllSolutions |
'Expand All Solutions' |
translate.CollapseAllSolutions |
'Collapse All Solutions' |
translate.Collapse |
'Collapse' |
translate.Episodes |
'Episodes' |
translate.GiveFeedback |
'Give Feedback' |
translate.LearnMore |
'Learn More' |
In addition, there are 27 translations that are inserted before they get to varnish:
variable | string |
---|---|
OUTPUT |
'OUTPUT' |
WARNING |
'WARNING' |
ERROR |
'ERROR' |
Overview |
'Overview' |
Questions |
'Questions' |
Objectives |
'Objectives' |
Callout |
'Callout' |
Challenge |
'Challenge' |
Prereq |
'Prerequisite' |
Checklist |
'Checklist' |
Discussion |
'Discussion' |
Testimonial |
'Testimonial' |
Caution |
'Caution' |
Keypoints |
'Key Points' |
Show me the solution |
'Show me the solution' |
Give me a hint |
'Give me a hint' |
Show details |
'Show details' |
Instructor Note |
'Instructor Note' |
SummaryAndSetup |
'Summary and Setup' |
SummaryAndSchedule |
'Summary and Schedule' |
AllInOneView |
'All in One View' |
PageNotFound |
'Page not found' |
AllImages |
'All Images' |
Anchor |
'anchor' |
Figure |
'Figure {element}' |
ImageOf |
'Image {i} of {n}: {sQuote(txt)}' |
Finish |
'Finish' |
pkgdown metadata
Another source of metadata is that created for the pkgdown in a file
called site/_pkgdown.yaml
.
# ------------------------------------------------------------------ information
# This file was generated by sandpaper version '0.16.10.9000'
# If you want to make changes, please edit '/tmp/RtmpercEqO/file2b422c29612b/config.yaml'
# ------------------------------------------------------------------ information
title: An Example Lesson
lang: en
home:
title: Home
strip_header: yes
description: ~
template:
package: varnish
params:
time: 2024-11-07 18:55:57 +0000
source: https://github.com/carpentries/file2b422c29612b
branch: main
contact: team@carpentries.org
license: CC-BY 4.0
handout: ~
cp: no
lc: no
dc: no
swc: no
carpentry: incubator
carpentry_name: Carpentries Incubator
carpentry_icon: incubator
life_cycle: pre-alpha
pre_alpha: yes
alpha: no
beta: no
stable: no
doi: ~
title: An Example Lesson
created: '2024-11-07'
keywords: software, data, lesson, The Carpentries
episodes: ~
learners: ~
instructors: ~
profiles: ~
This file is what allows {pkgdown} to recognise that a website needs
to be built. These variables are compiled into the pkg
variable that is passed to all downstream files from
build_site()
. The important elements we use are
-
$lang
stores the language variable -
$src_path
stores the source path of the lesson (thesite/
directory, or the location of theSANDPAPER_SITE
environment variable). -
$dst_path
stores the destination path to the lesson (site/docs
). NOTE: this particular path could be changed inbuild_site()
so that we update the name of the path so that it’s less confusing. The docs folder was a mechanism for pkgdown to locally deploy the site without having to affect the package structure (it was also a mechanism to serve GitHub pages in the past). -
$meta
a list of items passed on to {varnish}
snd <- asNamespace("sandpaper")
pkg <- pkgdown::as_pkgdown(snd$path_site(lsn))
pkg[c("lang", "src_path", "dst_path", "meta")]
## $lang
## [1] "en"
##
## $src_path
## /tmp/RtmpercEqO/file2b422c29612b/site
##
## $dst_path
## /tmp/RtmpercEqO/file2b422c29612b/site/docs
##
## $meta
## $meta$title
## [1] "An Example Lesson"
##
## $meta$lang
## [1] "en"
##
## $meta$home
## $meta$home$title
## [1] "Home"
##
## $meta$home$strip_header
## [1] TRUE
##
## $meta$home$description
## NULL
##
##
## $meta$template
## $meta$template$package
## [1] "varnish"
##
## $meta$template$params
## $meta$template$params$time
## [1] "2024-11-07 18:55:57 +0000"
##
## $meta$template$params$source
## [1] "https://github.com/carpentries/file2b422c29612b"
##
## $meta$template$params$branch
## [1] "main"
##
## $meta$template$params$contact
## [1] "team@carpentries.org"
##
## $meta$template$params$license
## [1] "CC-BY 4.0"
##
## $meta$template$params$handout
## NULL
##
## $meta$template$params$cp
## [1] FALSE
##
## $meta$template$params$lc
## [1] FALSE
##
## $meta$template$params$dc
## [1] FALSE
##
## $meta$template$params$swc
## [1] FALSE
##
## $meta$template$params$carpentry
## [1] "incubator"
##
## $meta$template$params$carpentry_name
## [1] "Carpentries Incubator"
##
## $meta$template$params$carpentry_icon
## [1] "incubator"
##
## $meta$template$params$life_cycle
## [1] "pre-alpha"
##
## $meta$template$params$pre_alpha
## [1] TRUE
##
## $meta$template$params$alpha
## [1] FALSE
##
## $meta$template$params$beta
## [1] FALSE
##
## $meta$template$params$stable
## [1] FALSE
##
## $meta$template$params$doi
## NULL
##
## $meta$template$params$title
## [1] "An Example Lesson"
##
## $meta$template$params$created
## [1] "2024-11-07"
##
## $meta$template$params$keywords
## [1] "software, data, lesson, The Carpentries"
##
## $meta$template$params$episodes
## NULL
##
## $meta$template$params$learners
## NULL
##
## $meta$template$params$instructors
## NULL
##
## $meta$template$params$profiles
## NULL
Before being sent to be rendered, it goes through one more
transformation, which is where the variable contexts you find in
{varnish} come from. The contexts that we use are site
for
the root path and title, yaml
for lesson-wide content, and
lang
to define the language. Everything else is not
used.
dat <- pkgdown::data_template(pkg)
writeLines(yaml::as.yaml(dat[c("lang", "site", "yaml")]))
## lang: en
## site:
## root: ''
## title: An Example Lesson
## yaml:
## time: 2024-11-07 18:55:57 +0000
## source: https://github.com/carpentries/file2b422c29612b
## branch: main
## contact: team@carpentries.org
## license: CC-BY 4.0
## handout: ~
## cp: no
## lc: no
## dc: no
## swc: no
## carpentry: incubator
## carpentry_name: Carpentries Incubator
## carpentry_icon: incubator
## life_cycle: pre-alpha
## pre_alpha: yes
## alpha: no
## beta: no
## stable: no
## doi: ~
## title: An Example Lesson
## created: '2024-11-07'
## keywords: software, data, lesson, The Carpentries
## episodes: ~
## learners: ~
## instructors: ~
## profiles: ~
## .present: yes