#' Render page with template
#'
#' Each page is composed of four templates: "head", "header", "content", and
#' "footer". Each of these templates is rendered using the `data`, and
#' then assembled into an overall page using the "layout" template.
#'
#' @param pkg Path to package to document.
#' @param name Name of the template (e.g. "home", "vignette", "news")
#' @param data Data for the template.
#'
#' This is automatically supplemented with three lists:
#'
#' * `site`: `title` and path to `root`.
#' * `yaml`: the `template` key from `_pkgdown.yml`.
#' * `package`: package metadata including `name` and`version`.
#'
#' See the full contents by running [data_template()].
#' @param path Location to create file; relative to destination directory.
#' @param depth Depth of path relative to base directory.
#' @param quiet If `quiet`, will suppress output messages
#' @export
render_page <- function(pkg = ".", name, data, path, depth = NULL, quiet = FALSE) {
pkg <- as_pkgdown(pkg)
if (is.null(depth)) {
depth <- dir_depth(path)
}
html <- render_page_html(pkg, name = name, data = data, depth = depth)
tweak_page(html, name, pkg = pkg)
activate_navbar(html, data$output_file %||% path, pkg)
rendered <- as.character(html, options = character())
write_if_different(pkg, rendered, path, quiet = quiet)
}
render_page_html <- function(pkg, name, data = list(), depth = 0L) {
data <- modify_list(data_template(pkg, depth = depth), data)
# render template components
pieces <- c(
"head",
"in-header",
"before-body",
"navbar",
"content",
"footer",
"after-body",
if (pkg$bs_version == 3) c("header", "docsearch")
)
templates <- purrr::map_chr(pieces, find_template, name = name, pkg = pkg)
components <- purrr::map(templates, render_template, data = data)
components <- purrr::set_names(components, pieces)
components$template <- name
components$lang <- pkg$lang
components$translate <- data$translate
# render complete layout
template <- find_template("layout", name, pkg = pkg)
rendered <- render_template(template, components)
# Strip trailing whitespace
rendered <- gsub(" +\n", "\n", rendered, perl = TRUE)
xml2::read_html(rendered, encoding = "UTF-8")
}
#' @export
#' @rdname render_page
data_template <- function(pkg = ".", depth = 0L) {
pkg <- as_pkgdown(pkg)
out <- list()
# Basic metadata
out$package <- list(
name = pkg$package,
version = as.character(pkg$version)
)
if (has_logo(pkg)) {
out$logo <- list(src = logo_path(pkg, depth = depth))
}
out$site <- list(
root = up_path(depth),
title = config_pluck_string(pkg, "title", default = pkg$package)
)
out$year <- strftime(Sys.time(), "%Y")
# Language and translations
out$lang <- pkg$lang
out$translate <- list(
skip = tr_("Skip to contents"),
toggle_nav = tr_("Toggle navigation"),
on_this_page = tr_("On this page"),
source = tr_("Source"),
abstract = tr_("Abstract"),
authors = tr_("Authors"),
version = tr_("Version"),
examples = tr_("Examples"),
citation = tr_("Citation"),
author_details = tr_("Additional details"),
toc = tr_("Table of contents"),
site_nav = tr_("Site navigation")
)
# Components that mostly end up in the <head>
out$has_favicons <- has_favicons(pkg)
out$opengraph <- data_open_graph(pkg)
out$extra <- list(
css = path_first_existing(pkg$src_path, "pkgdown", "extra.css"),
js = path_first_existing(pkg$src_path, "pkgdown", "extra.js")
)
out$includes <- config_pluck(pkg, "template.includes")
out$yaml <- config_pluck(pkg, "template.params")
# Force inclusion so you can reliably refer to objects inside yaml
# in the mustache templates
out$yaml$.present <- TRUE
if (pkg$bs_version > 3) {
out$headdeps <- data_deps(pkg = pkg, depth = depth)
}
# Development settings; tooltip needs to be generated at render time
out$development <- pkg$development
out$development$version_tooltip <- version_tooltip(pkg$development$mode)
out$navbar <- data_navbar(pkg, depth = depth)
out$footer <- data_footer(pkg)
out$lightswitch <- uses_lightswitch(pkg)
out$uses_katex <- config_math_rendering(pkg) == "katex"
print_yaml(out)
}
data_open_graph <- function(pkg = ".", call = caller_env()) {
pkg <- as_pkgdown(pkg)
og <- config_pluck_list(pkg, "template.opengraph", default = list())
og <- check_open_graph(pkg, og, call = call)
logo <- find_logo(pkg$src_path)
if (is.null(og$image) && !is.null(logo)) {
og$image <- list(src = path_file(logo))
}
if (!is.null(og$image) && !grepl("^http", og$image$src)) {
site_url <- config_pluck(pkg, "url", default = "/")
if (!grepl("/$", site_url)) {
site_url <- paste0(site_url, "/")
}
og$image$src <- gsub("^man/figures/", "reference/figures/", og$image$src)
og$image$src <- paste0(site_url, og$image$src)
}
if (!is.null(og$twitter)) {
og$twitter$card <- og$twitter$card %||% "summary"
og$twitter$creator <- og$twitter$creator %||% og$twitter$site
og$twitter$site <- og$twitter$site %||% og$twitter$creator
}
og
}
check_open_graph <- function(pkg, og, file_path = NULL, call = caller_env()) {
if (is.null(og)) {
return()
}
is_yaml <- is.null(file_path)
base_path <- if (is_yaml) "template.opengraph" else "opengraph"
check_open_graph_list(
pkg,
og,
file_path = file_path,
error_path = base_path,
error_call = call
)
supported_fields <- c("image", "twitter")
unsupported_fields <- setdiff(names(og), supported_fields)
if (length(unsupported_fields)) {
msg <- "{.field {base_path}} contains unsupported fields {.val {unsupported_fields}}."
config_warn(pkg, msg, path = file_path, call = call)
}
check_open_graph_list(
pkg,
og$twitter,
file_path = file_path,
error_path = paste0(base_path, ".twitter"),
error_call = call
)
if (!is.null(og$twitter) && is.null(og$twitter$creator) && is.null(og$twitter$site)) {
msg <- "{.field opengraph.twitter} must include either {.field creator} or {.field site}."
config_abort(pkg, msg, path = file_path, call = call)
}
check_open_graph_list(
pkg,
og$image,
file_path = file_path,
error_path = paste0(base_path, ".image"),
error_call = call
)
og[intersect(supported_fields, names(og))]
}
render_template <- function(path, data) {
template <- read_file(path)
if (length(template) == 0)
return("")
whisker::whisker.render(template, data)
}
check_open_graph_list <- function(pkg,
x,
file_path,
error_path,
error_call = caller_env()) {
if (is.list(x) || is.null(x)) {
return()
}
not <- obj_type_friendly(x)
config_abort(
pkg,
"{.field {error_path}} must be a list, not {not}.",
path = file_path,
call = error_call
)
}
write_if_different <- function(pkg, contents, path, quiet = FALSE, check = TRUE) {
# Almost all uses are relative to destination, except for rmarkdown templates
full_path <- path_abs(path, start = pkg$dst_path)
if (check && !made_by_pkgdown(full_path)) {
cli::cli_inform("Skipping {.file {path}}: not generated by pkgdown")
return(FALSE)
}
if (same_contents(full_path, contents)) {
# touching the file to update its modification time
# which is important for proper lazy behavior
file_touch(full_path)
return(FALSE)
}
if (!quiet) {
writing_file(path_rel(full_path, pkg$dst_path), path)
}
write_lines(contents, path = full_path)
TRUE
}
same_contents <- function(path, contents) {
if (!file_exists(path))
return(FALSE)
new_hash <- digest::digest(contents, serialize = FALSE)
cur_contents <- paste0(read_lines(path), collapse = "\n")
cur_hash <- digest::digest(cur_contents, serialize = FALSE)
identical(new_hash, cur_hash)
}
file_digest <- function(path) {
if (file_exists(path)) {
digest::digest(file = path, algo = "xxhash64")
} else {
"MISSING"
}
}
made_by_pkgdown <- function(path) {
if (!file_exists(path)) return(TRUE)
first <- paste(read_lines(path, n = 2), collapse = "\n")
check_made_by(first)
}
check_made_by <- function(first) {
if (length(first) == 0L) return(FALSE)
grepl("<!-- Generated by pkgdown", first, fixed = TRUE)
}
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