R/send.R

In Gastrograph/RMandrill: This package is an api wrapper for R to use mandrill

#' Send an email with template
#'
#' This sends an email with template
#'
#' @param api_key Your Stripe API Key
#'
#' @param template_name name of template on Mandrill to use
#' @param variables list of merge variables used in template to be filled in
#' @param subject character vector (single element) to populate email subject line
#' @param recipient character vector of email addresses of recipients
#' @param sender character vector of senders' email addresses
#' @param contents list HTML  contents to be replaced in Mandrill template.  These are used to replace content
#' between HTML tags that have a CSS class of `mc:edit="content_name"` where the name of the object in the list
#' must match the the `content_name` in in the template.
#' @param images character vector denoting location of PNGs to include in email. PNG file names (minus the suffix and
#' any preceeding path directories) must match the image declaration in the Mandrill template.
#' @param attachments character vector denoting location of attachments to include in email.
#' @param css whether to include inline CSS or not.  This CSS must be already present in the Mandrill template
#'
#' @return contents of HTTP Response.
#'
#' @export
#'
mandrill_send_template <- function(api_key = NA,
                                   template_name = NA,
                                   variables = NA,
                                   subject = NA,
                                   recipient = NA,
                                   sender = NA,
                                   contents = NULL,
                                   images = NULL,
                                   attachments = NULL,
                                   css = FALSE) {

  to <- data.frame(email = recipient,
                   stringsAsFactors = FALSE)

  merge_vars <- data.frame(rcpt = recipient,
                           stringsAsFactors = FALSE)

  merge_vars$vars <- list(variables)

  images_out <- NA

  if (!missing(images)) {
    images_out <- dplyr::rbind_all(lapply(images, process_images))
  }


  attachments_out <- NA

  if (!missing(attachments)) {
    attachments_out <- dplyr::rbind_all(lapply(attachments,
                                               process_attachments
                                               )
                                        )
  }

  template_contents <- data.frame()
  if (!missing(contents)) {
    for (content in names(contents)) {
      content_name <- content
      out_df <- data.frame(name = content_name,
                           content = contents[[content]])
      template_contents <- rbind(template_contents, out_df)
    }
  }


  sendData <- list(key = api_key,
                   template_name = template_name,
                   template_content = template_contents,
                   message = list(subject = subject,
                                merge_vars = merge_vars,
                                to = to,
                                from_email = sender,
                                images = images_out,
                                attachments = attachments_out,
                                inline_css = css
                                )
                   )
  link <- "https://mandrillapp.com/api/1.0/messages/send-template.json"
  jsonData <- jsonlite::toJSON(sendData, auto_unbox = TRUE)
  .post(link, jsonData)
}

.post <- function(link, data) {
  res <- httr::POST(url = link,
                    httr::user_agent(agent = "Mandrill-Curl/1.0"),
                    body = data
                    )
  httr::content(res)
}