Merge pull request #163 from hrbrmstr/master

tweet shot + other cleanup

DESCRIPTION

@@ -26,7 +26,11 @@ Suggests:
     ggplot2,
     knitr,
     rmarkdown,
-    testthat
+    testthat,
+    glue,
+    magick,
+    webshot,
+    scales
 VignetteBuilder: knitr
 LazyData: yes
 RoxygenNote: 6.0.1.9000

NAMESPACE

@@ -85,6 +85,7 @@ export(suggested_users)
 export(trends_available)
 export(ts_data)
 export(ts_plot)
+export(tweet_shot)
 export(tweets_data)
 export(tweets_with_users)
 export(uq_rtweet)

R/get-my-timeline.R

@@ -11,14 +11,9 @@
 #'   Must be of length 1 or equal to length of user.
 #' @param max_id Character, status_id from which returned tweets
 #'   should be older than.
-#' @param home Logical, indicating whether to return a user-timeline
-#'   or home-timeline. By default, home is set to FALSE, which means
-#'   \code{get_timeline} returns tweets posted by the given user. To
-#'   return a user's home timeline feed, that is, the tweets posted by
-#'   accounts followed by a user, set the home to false.
 #' @param parse Logical, indicating whether to return parsed
 #'   (data.frames) or nested list object. By default, \code{parse =
-#'   TRUE} saves users from the time [and frustrations] associated
+#'   TRUE} saves users from the time (and frustrations) associated
 #'   with disentangling the Twitter API return objects.
 #' @param check Logical indicating whether to remove check available
 #'   rate limit. Ensures the request does not exceed the maximum

R/next_cursor.R

@@ -134,6 +134,7 @@ get_max_id <- function(x) {
 
 
 #' @rdname next_cursor
+#' @param .x id
 #' @export
 max_id <- function(.x) UseMethod("max_id")
 

R/tweet_shot.R

@@ -0,0 +1,84 @@
+#' Capture an image of a tweet/thread
+#'
+#' Provide a status id or a full Twitter link to a tweet and this function
+#' will capture an image of the tweet --- or tweet + thread (if there are
+#' Twitter-linked replies) --- from the mobile version of said tweet/thread.
+#'
+#' For this to work, you will need to ensure the packages in `Suggests:` are
+#' installed as they will be loaded upon the first invocation of this function.
+#'
+#' Use the `zoom` factor to get more pixels which may improve the text rendering
+#' of the tweet/thread.
+#'
+#' @md
+#' @param statusid_or_url a valid Twitter status id (e.g. "`947082036019388416`") or
+#'     a valid Twitter status URL (e.g. "`https://twitter.com/jhollist/status/947082036019388416`").
+#' @param zoom a positive number >= 1. See the help for `[webshot::webshot()]` for more information.
+#' @param scale auto-scale the image back to 1:1? Default it `TRUE`, which means `magick`
+#'     will be used to return a "normal" sized tweet. Set it to `FALSE` to perform your
+#'     own image manipulation.
+#' @return `magick` object
+#' @export
+#' @examples \dontrun{
+#' tweet_shot("947082036019388416")
+#' tweet_shot("https://twitter.com/jhollist/status/947082036019388416")
+#' }
+tweet_shot <- function(statusid_or_url, zoom=3, scale=TRUE) {
+
+  statusid_or_url <- statusid_or_url[1]
+  zoom <- zoom[1]
+  scale <- scale[1]
+
+  if (zoom <= 1) stop("zoom must be a positive number, >= 1", call.=FALSE)
+  if (!is.logical(scale)) stop("scale must be TRUE/FALSE", call.=FALSE)
+
+  # can we do it?
+  try_require("glue", "glue_data")
+  try_require("magick", "image_read")
+  try_require("webshot", "webshot")
+  try_require("scales", "percent")
+
+  # yes we can! (if the function got to this point)
+
+  x <- statusid_or_url
+
+  # first test if we have a Twitter URL
+  is_url <- grepl("^http[s]://", x)
+
+  if (is_url) { # mebbe, let's look further
+
+    is_twitter <- grepl("twitter", x) # shld have "twitter" in it
+    if (!is_twitter) stop("statusid_or_url must be a valid Twitter status id or URL", call.=FALSE)
+
+    is_status <- grepl("status", x) # shld also have "status" in it
+    if (!is_status) stop("statusid_or_url must be a valid Twitter status id or URL", call.=FALSE)
+
+    already_mobile <- grepl("://mobile\\.", x) # if it's not a mobile status, make it one
+    if (!already_mobile) x <- sub("://twi", "://mobile.twi", x)
+
+  } else { # let's see if it's a status id
+
+    x <- rtweet::lookup_tweets(x)
+    if (!(nrow(x) > 0)) stop("Twitter status not found", call.=FALSE) # nope
+
+    # make a mobile URL
+    x <- glue::glue_data(x, "https://mobile.twitter.com/{screen_name}/status/{status_id}")
+
+  }
+
+  # keep the filesystem clean
+  tf <- tempfile(fileext = ".png")
+  on.exit(unlink(tf), add=TRUE) # it'll clean up for us
+
+  # capture the tweet
+  webshot::webshot(url=x, file=tf, zoom=zoom)
+
+  img <- magick::image_read(tf) # read the image in
+  img <- magick::image_trim(img) # remove the extraneous border
+
+  # scale if we want to
+  if ((zoom > 1) && (scale)) img <- magick::image_scale(img, scales::percent(1/zoom))
+
+  img
+
+}

R/utils.R

@@ -564,6 +564,20 @@ obs2string <- function(x, sep) {
   paste(x, collapse = sep)
 }
 
+# Enables loading packages when necessary vs import
+
+try_require <- function(pkg, f) {
+
+  if (requireNamespace(pkg, quietly = TRUE)) {
+    library(pkg, character.only = TRUE)
+    return(invisible())
+  }
+
+  stop("Package `", pkg, "` required for `", f , "`.\n",
+    "Please install and try again.", call. = FALSE)
+}
+
 is.valid.username <- function(username) {
   !grepl(' ', username);
 }
+