Render multiple documents as a website

Source: R/render_site.R

Render all of the R Markdown documents within a directory as a website.

render_site(
  input = ".",
  output_format = "all",
  envir = parent.frame(),
  quiet = FALSE,
  encoding = "UTF-8"
)

clean_site(input = ".", preview = TRUE, quiet = FALSE, encoding = "UTF-8")

site_generator(input = ".", output_format = NULL)

site_config(input = ".", encoding = "UTF-8")

default_site_generator(input, output_format_filter = NULL, ...)

Arguments

input

Website directory (or the name of a file within the directory).

output_format

R Markdown format to convert to (defaults to "all").

envir

The environment in which the code chunks are to be evaluated during knitting (can use new.env to guarantee an empty new environment).

quiet

TRUE to suppress messages and other output.

encoding

Ignored. The encoding is always assumed to be UTF-8.

preview

Whether to list the files to be removed rather than actually removing them. Defaulting to TRUE to prevent removing without notice.

output_format_filter

An optional function which is passed the input file and the output format, and which returns a (potentially modified) output format.

...

Currently unused.

Value

render_site returns the name of the site output file (relative to the input directory). clean_site returns the names of the generated files removed during cleaning. site_config returns the contents of _site.yml as an R list. default_site_generator returns the default site generator for R Markdown websites.

Details

The render_site function enables you to render a collection of markdown documents within a directory as a website. There are two requirements for a directory to be rendered as a website:

  1. It must contain either an "index.Rmd" or "index.md" file.

  2. It must contain a site configuration file ("_site.yml").

The most minimal valid website is an empty "index.Rmd" and an empty "_site.yml". With this configuration a single empty webpage would be generated via a call to render_site. If you add additional markdown documents to the directory they will also be rendered. By default a site is rendered in the following fashion:

  1. R Markdown (.Rmd) and plain markdown (.md) files in the root directory are rendered. Note however that markdown files beginning with "_" are not rendered (this is a convention to designate files that are included by top level documents).

  2. All output and supporting files are copied to a "_site" subdirectory of the website directory (this is configurable, see discussion below).

  3. The following files are not copied to the "_site" sub-directory:

    • Files beginning with "." (hidden files).

    • Files beginning with "_"

    • Files known to contain R source code (e.g. ".R", ".s", ".Rmd"), R data (e.g. ".RData", ".rds"), configuration data (e.g. ".Rproj", "rsconnect") or package project management data (e.g. "packrat", "renv").

    Note that you can override which files are included or excluded via settings in "_site.yml" (described below).

  4. Normally R Markdown renders documents as self-contained HTML. However, render_site ensures that dependencies (e.g. CSS, JavaScript, images, etc.) remain in external files. CSS/JavaScript libraries are copied to a "site_libs" sub-directory and plots/images are copied to "_files" sub-directories.

You can remove the files generated by render_site using the clean_site function.

Configuration

A "_site.yml" file can be used to configure the behavior of site generation. Here is an example configuration file:


name: my-website
output_dir: _site
include: ["demo.R"]
exclude: ["docs.txt", "*.csv"]
navbar:
  title: "My Website"
  left:
    - text: "Home"
      href: index.html
    - text: "About"
      href: about.html
output:
  html_document:
    toc: true
    highlight: textmate

The name field provides a suggested URL path for your website when it is published (by default this is just the name of the directory containing the site). The output_dir indicates which directory to copy site content into ("_site" is the default if none is specified). Note that this can be "." to keep all content within the root website directory alongside the source code.

The include and exclude fields enable you to override the default behavior vis-a-vis what files are copied into the "_site" directory (wildcards can be used as in the above example).

The navbar field can be used to define a navigation bar for websites based on the html_document format.

Finally, the output field enables you to specify output options that are common to all documents within the website (you can also still provide local options within each document that override any common options).

new_session: true causes each file to be rendered in a new R session. This prevents the masking problem that arises when different files use functions from different packages (namespaces) that share a common name, such as here::here and lubridate::here or dplyr::filter and MASS::filter. The default behaviour of render_site is to use a common R session.

autospin: true causes .R files to be spinned and rendered (as well as .Rmd files). If autospin is set to false (the default), .R files will not be spinned nor rendered. autospin can also enumerate a list of .R files to be spinned and rendered.

Custom Site Generation

The behavior of the default site generation function (rmarkdown::default_site) is described above. It is also possible to define a custom site generator that has alternate behavior. A site generator is an R function that is bound to by including it in the "site:" field of the "index.Rmd" or "index.md" file. For example:


title: "My Book"
output: bookdown::gitbook
site: bookdown::bookdown_site

A site generation function should return a list with the following elements:

name:

The name for the website (e.g. the parent directory name).

output_dir:

The directory where the website output is written to. This path should be relative to the site directory (e.g. "." or "_site")

render:

An R function that can be called to generate the site. The function should accept the input_file, output_format, envir, and quiet arguments.

clean:

An R function that returns relative paths to the files generated by render_site (these files are the ones which will be removed by the clean_site function.

subdirs (optional):

A logical flag that indicates if the generator supports nested source files in subdirectories of the project (TRUE) or only at the project root (FALSE). (e.g. blogdown:::blogdown_site())

Note that the input_file argument will be NULL when the entire site is being generated. It will be set to a specific file name if a front-end tool is attempting to preview it (e.g. RStudio IDE via the Knit button).

When quiet = FALSE the render function should also print a line of output using the message function indicating which output file should be previewed, for example:

if (!quiet)
  message("\nOutput created: ", output)

Emitting this line enables front-ends like RStudio to determine which file they should open to preview the website.

See the source code of the rmarkdown::default_site function for a example of a site generation function.