rmd2wp:

# Determine title from .Rmd file
determine_title <- function(file){
  library(stringr)
  lines <- readLines(file)
  title.lines <- lines[grepl('title:',lines)]
  if(length(title.lines) == 1){
    title <- str_split(title.lines,'title:')[[1]][2]
    title <- str_replace_all(title,'\"','')
    title <- str_trim(title,side = 'left')
  } else if(length(title.lins) > 1){
    stop('Title Ambiguous.')
  }
  title <- str_trim(title)
  return(title)
}

# Check if post with same title exists.  Returns that post's ID.
checkPostExistence <- function(title){
  posts <- RWordPress::getPosts()
  # Find Post ID
  postID <- as.numeric(as.character(posts[str_trim(toupper(posts$title))==str_trim(toupper(title)),'postid']))
  if(length(postID)>1) stop('Ambiguous Post Title. Multiple posts exist with same title.')
  return(ifelse(length(postID)==1,postID,NA))
}

checkPageExistence <- function(title){
  pages <- RWordPress::getPages()
  # Find Post ID
  pageID <- as.numeric(as.character(pages[str_trim(toupper(pages$title))==str_trim(toupper(title)),'page_id']))
  if(length(pageID)>1) stop('Ambiguous Post Title. Multiple posts exist with same title.')
  return(ifelse(length(pageID)==1,pageID,NA))
}

shorten_url <- function(url){
  if(checkBitlyStatus()){
    library(RBitly)
    shortened_url <- links_Shorten(url)$url
  }
  return(shortened_url)
}
checkBitlyStatus <- function(){
  library(RBitly)
  check <- try(suppressMessages(user_TrackingDomains()),silent=TRUE)
  if(!is.null(attr(check,'class'))){
    warning('\n  RBitly authentication not correctly set up.\n  See help(rbitlyApi) for more details.')
  }
  return(is.null(attr(check,'class')))
}

# Check whether twitteR authentication was appropriately set up
checkTwitterStatus <- function(){
  library(twitteR)
  check <- try(getUser('RobWeyant'),silent=TRUE)
  if(attr(check,'class')=='try-error'){
    warning('\n  twitteR authentication not correctly set up.\n  See help(setup_twitter_oauth) for more details.')
  }
  return(attr(check,'class')!='try-error')
}

# Tweet about new post
tweetPost <- function(title='',
                      categories='',
                      tags='',
                      other.hashtags='',
                      useURLShortener=FALSE){
  library(twitteR)

  tryCatch(
    {
      postID <- checkPostExistence(title)
      url0 <- getOption('WordpressURL')
      url1 <- str_replace(url0,'xmlrpc.php','')
      tweet.url <- paste(url1,'?p=',postID,sep='')
      if(useURLShortener) tweet.url <- shorten_url(tweet.url)

      # Create tweet
      pre_hashtags <- c(categories,tags,other.hashtags)
      pre_hashtags <- pre_hashtags[pre_hashtags!='']
      hashtags <- paste('#',unique(pre_hashtags),sep='', collapse=' ')
      full.tweet <- paste(title,hashtags,tweet.url)
      tweet(full.tweet)
    })
}

# in .Rprofile
# options(WordpressLogin=('username'='password'),
#         WordpressURL='http://www.yourblog.com/xmlrpc.php')
postToBlog.dev <- function(file,
                       title=NA,
                       categories=c(),
                       tags=c(),
                       postID=NA,
                       toc=TRUE,
                       type=c('new','edit','CreateOrReplace'),
                       syntax.highlighter='Syntax Highlighter Evolved',
                       page=FALSE,
                       publish=FALSE,
                       createTweet=FALSE,
                       categoriesAsHashTags=TRUE,
                       tagsAsHashTags=TRUE,
                       other.hashtags='',
                       useURLShortener=FALSE,
                       verbose=TRUE){

  # Load dependencies
  library(RWordPress)
  library(knitr)
  library(markdown)
  library(stringr)
  library(tools)

  # This is kind of a hack -- need to find a better solution (!!!).
  categories <- c(categories,'')

  # Determine what kind of action to take
  type <- match.arg(type)

  # Determine file name of .html output file
  file.name <- basename(file)
  dir.name <- dirname(file)
  file.extension <- file_ext(file.name)
  current.directory <- getwd()
  setwd(dir.name)

  # Check that file passed was .Rmd
  if(file.extension!='Rmd'){
    stop("File extension is not .Rmd.  Check input file to make sure it is correct format.")
  }

  # Determine what the HTML file will be called
  file.root <- str_split(file.name,pattern = paste('.',file.extension,sep=''))[[1]][1]
  html.file <- paste(file.root,'.html',sep='')

  # Print inputs
  if(verbose){
    cat('Directory:\t\t',dir.name,'\n')
    cat('RMarkdown file:\t\t', file.name,'\n')
    cat('HTML file:\t\t', html.file,'\n')
    cat('Blog URL:\t\t', getOption('WordpressURL'),'\n')
    cat('Action Type:\t\t', type,'\n')
    cat('Syntax Highlighter:\t',syntax.highlighter,'\n')
    cat('Tags:\t\t\t',tags,'\n')
    cat('Categories:\t\t',categories,'\n')
  }

  # Set some markdown options
  options(markdown.HTML.options =  c('use_xhtml','base64_images','mathjax','highlight_code',"hard_wrap","toc"))
  if(!toc) options(markdown.HTML.options =  c('use_xhtml','base64_images','mathjax','highlight_code',"hard_wrap"))

  # Knit an HTML file
  knit2html(file.name,quiet=TRUE)

  # Get Title From .Rmd
  if(is.na(title)) title <- determine_title(file.name)

  # Get Post ID
  if(is.na(postID) && !page ) postID <- checkPostExistence(title)
  if(is.na(postID) && page ) postID <- checkPageExistence(title)

  # Create New Post
  if(is.na(postID) || type=='new') {
    if(page){
      if(verbose) print('Creating New Page')
      newPage(content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                           title=title),
              publish=publish)
    } else {
      if(verbose) print('Creating New Post')
      newPost(content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                           title=title,
                           categories=categories,
                           mt_keywords=tags),
              publish=publish)
    }
  }  else if (!is.na(postID)) {
    if(page){
      # Edit Existing Post
      if(verbose) print('Editing Old Page')
      editPost(postid = postID,
               content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                    title=title),
               publish=publish)

    } else {
      # Edit Existing Post
      if(verbose) print('Editing Old Post')
      editPost(postid = postID,
               content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                            title=title,
                            categories=categories,
                            mt_keyworkds=tags),
               publish = publish)
    }
  } else{
    warning('Not Sure what to do.  No posts created or updated.')
  }

  # Create a tweet if requested and the blog is getting published
  if(!categoriesAsHashTags) categories=c()
  if(!tagsAsHashTags) tags=c()
  if(createTweet && publish) tweetPost(title,
                                       categories,
                                       tags,
                                       other.hashtags,
                                       useURLShortener=useURLShortener
                                       )

  # Go back to directory where function was called
  setwd(current.directory)
}


postToBlog.deprecated <- function(file,
                       title='',
                       categories=c(),
                       tags=c(),
                       postID=NULL,
                       toc=TRUE,
                       type=c('new','edit'),
                       syntax.highlighter='Syntax Highlighter Evolved',
                       publish=FALSE){

  library(RWordPress)
  library(knitr)
  library(markdown)
  library(stringr)
  library(tools)

  # Determine what kind of action to take
  type <- match.arg(type)

  ## Determine file name of .html output file
  file.name <- basename(file)
  dir.name <- dirname(file)

  file.extension <- file_ext(file.name)

  # Should this be a stop()?
  if(file.extension!='Rmd'){
    warning("File extension is not .Rmd.  Check input file to make sure it is correct format.")
  }

  file.root <- str_split(basename(file),pattern = paste('.',file.extension,sep=''))[[1]][1]
  html.file <- paste(file.root,'.html',sep='')
  current.director <- getwd()
  setwd(dir.name)

  cat('Directory:',dir.name,'\n')
  cat('RMarkdown file:', file.name,'\n')
  cat('HTML file:', html.file,'\n')
  cat('Blog URL:', getOption('WordpressURL'),'\n')
  cat('Action Type:', type,'\n')
  cat('Syntax Highlighter:',syntax.highlighter,'\n')

  # in .Rprofile
  # options(WordpressLogin=('username'='password'),
  #         WordpressURL='http://www.yourblog.com/xmlrpc.php')

  # Table of Contents
  options(markdown.HTML.options =  c('use_xhtml','base64_images','mathjax','highlight_code',"toc","hard_wrap"))
  # options(markdown.HTML.options =  c(markdownHTMLOptions(default = T),"number_sections"))

  # Knit an HTML file
  knit2html(file.name)

  # If new category is used then create that category
  # Does not work
  if(length(categories)>=1 && FALSE){
    current.categories <- names(RWordPress::categories())
    new.categories <- !(categories %in% current.categories)
    sapply(categories[new.categories],function(x){
      newCategory(x)
    })
  }

  ## NEW POST
  if(type=='new'){
    newPost(
      list(
        description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
        title=title,
        categories=categories,
        mt_keywords=tags
      ),
      publish=publish)
    ## EDIT POST
  } else if(type=='edit') {
    posts <- RWordPress::getPosts()
    if(is.null(postID)){

      # Find Post ID
      postID <- posts[posts$title==title,'postid']
      # Check that there is a post to edit
      if(length(postID)==1 && !is.null(postID) && !is.na(postID)){
        print(paste('Editing post [',postID,']: ',title,'.',sep=''))
        editPost(postid = postID,
                 content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                              title=title,
                              categories=categories,
                              mt_keyworkds=tags),
                 publish = publish
        )
      }
      ## Iff there is exactly 1 post that matches ID given
    } else if(sum(posts$postid==postID) == 1){
      print(paste('Editing post [',postID,']: ',title,'.',sep=''))
      editPost(postid = postID,
               content=list(description=knit2wordpress(html.file,syntax.highlighter=syntax.highlighter),
                            title=title,
                            categories=categories,
                            mt_keyworkds=tags),
               publish = publish
      )
    }
  }
  setwd(current.director)
}