R/initGitbook.R

In jbryer/Rgitbook: Gitbook Projects with R Markdown

#' Create files and folders based on contents of SUMMARY.md.
#' 
#' This first calls system command \code{gitbook init} but then will change
#' the all the file extensions from \code{.md} to \code{.Rmd} excluding
#' \code{SUMMARY.md} and \code{README.md}.
#' 
#' @param dir source directory for the Gitbook.
#' 
#' @export
initGitbook <- function(dir=getwd()) {
	dir <- normalizePath(dir)
	checkForGitbook(quiet=TRUE)
	oldwd <- setwd(dir)
	test <- system(paste0('gitbook init ', dir))
	if(test != 0) { stop("gitbook initalization failed") }
	mdfiles <- list.files(dir, '*.md', recursive=TRUE, full.names=TRUE)
	mdfiles <- mdfiles[-c(grep('README.md$', mdfiles),
						  grep('SUMMARY.md$', mdfiles))]
	mdfiles2 <- gsub('/.md$', '.Rmd', mdfiles)
	file.rename(mdfiles, mdfiles2)
	
	knitr.header <- c( # TODO: make a package option?
		"```{r knitsetup, echo=FALSE, results='hide', warning=FALSE, message=FALSE, cache=FALSE}",
		"opts_knit$set(base.dir='./', fig.path='', out.format='md')",
		"opts_chunk$set(prompt=TRUE, comment='', results='markup')",
		"# See yihui.name/knitr/options for more Knitr options.",
		"##### Put other setup R code here",
		"",
		"```",
		""
	)
	for(rmd in mdfiles2) {
		file <- file(rmd)
		lines <- readLines(file)
		close(file)
		
		#if the knitsetup block isn't already in the file, then add it
		suppressWarnings(
			if(grepl("r knitsetup.+\n", lines)) {
				lines <- c(knitr.header, lines)
			}
		)
		
		file <- file(rmd)
		writeLines(lines, file(rmd))
		close(file)
	}
	
	setwd(oldwd)
	invisible()
}