R: Define an HTML dependency

htmlDependency {htmltools}

R Documentation

Define an HTML dependency

Description

Define an HTML dependency (i.e. CSS and/or JavaScript bundled in a directory). HTML dependencies make it possible to use libraries like jQuery, Bootstrap, and d3 in a more composable and portable way than simply using script, link, and style tags.

Usage

htmlDependency(
  name,
  version,
  src,
  meta = NULL,
  script = NULL,
  stylesheet = NULL,
  head = NULL,
  attachment = NULL,
  package = NULL,
  all_files = TRUE
)

Arguments

`name`	Library name
`version`	Library version
`src`	Unnamed single-element character vector indicating the full path of the library directory. Alternatively, a named character string with one or more elements, indicating different places to find the library; see Details.
`meta`	Named list of meta tags to insert into document head
`script`	Script(s) to include within the document head (should be specified relative to the `src` parameter).
`stylesheet`	Stylesheet(s) to include within the document (should be specified relative to the `src` parameter).
`head`	Arbitrary lines of HTML to insert into the document head
`attachment`	Attachment(s) to include within the document head. See Details.
`package`	An R package name to indicate where to find the `src` directory when `src` is a relative path (see `resolveDependencies()`).
`all_files`	Whether all files under the `src` directory are dependency files. If `FALSE`, only the files specified in `script`, `stylesheet`, and `attachment` are treated as dependency files.

Details

Each dependency can be located on the filesystem, at a relative or absolute URL, or both. The location types are indicated using the names of the src character vector: file for filesystem directory, href for URL. For example, a dependency that was both on disk and at a URL might use src = c(file=filepath, href=url).

script can be given as one of the following:

a character vector specifying various scripts to include relative to the value of src. Each is expanded into its own ⁠<script>⁠ tag
A named list with any of the following fields:
- src,
- integrity, &
- crossorigin,
- any other valid ⁠<script>⁠ attributes.
allowing the use of SRI to ensure the integrity of packages downloaded from remote servers. Eg: script = list(src = "min.js", integrity = "hash")
An unnamed list, containing a combination of named list with the fields mentioned previously, and strings. Eg:
- script = list(list(src = "min.js"), "util.js", list(src = "log.js"))
- script = "pkg.js" is equivalent to
- script = list(src = "pkg.js").

attachment can be used to make the indicated files available to the JavaScript on the page via URL. For each element of attachment, an element ⁠<link id="DEPNAME-ATTACHINDEX-attachment" rel="attachment" href="...">⁠ is inserted, where DEPNAME is name. The value of ATTACHINDEX depends on whether attachment is named or not; if so, then it's the name of the element, and if not, it's the 1-based index of the element. JavaScript can retrieve the URL using something like ⁠document.getElementById(depname + "-" + index + "-attachment").href⁠. Note that depending on the rendering context, the runtime value of the href may be an absolute, relative, or data URI.

htmlDependency should not be called from the top-level of a package namespace with absolute paths (or with paths generated by system.file()) and have the result stored in a variable. This is because, when a binary package is built, R will run htmlDependency and store the path from the building machine's in the package. This path is likely to differ from the correct path on a machine that downloads and installs the binary package. If there are any absolute paths, instead of calling htmlDependency at build-time, it should be called at run-time. This can be done by wrapping the htmlDependency call in a function.

Value