Enabled streaming toots (fix #84)

DESCRIPTION

@@ -16,8 +16,10 @@ Depends:
     R (>= 3.6)
 Imports: 
     clipr,
+    curl,
     dplyr,
     httr,
+    jsonlite,
     tibble
 Suggests: 
     knitr,

NAMESPACE

@@ -31,8 +31,12 @@ export(get_timeline_hashtag)
 export(get_timeline_home)
 export(get_timeline_list)
 export(get_timeline_public)
+export(parse_stream)
 export(post_toot)
 export(post_user)
 export(search_accounts)
+export(stream_timeline_hashtag)
+export(stream_timeline_list)
+export(stream_timeline_public)
 export(verify_credentials)
 export(verify_envvar)

NEWS.md

@@ -3,7 +3,8 @@
 * possible to set token via environment variable (#68)
 * paginating results (#70)
 * adding ratelimit checking (#43)
-* added pkgdown site(#79)
+* added pkgdown site (#79)
+* added streaming (#84)
 
 # rtoot 0.1.0
 

R/stream_statuses.R

@@ -0,0 +1,183 @@
+#' Collect live streams of Mastodon data
+#' @name stream_timeline
+#' @param timeout Integer, Number of seconds to stream toots for. Stream indefinitely with timeout = Inf. The stream can be interrupted at any time, and file_name will still be a valid file.
+#' @param local	 logical, Show only local statuses (either statuses from your instance or the one provided in `instance`)?
+#' @param file_name character, name of file. If not specified, will write to a temporary file stream_toots*.json.
+#' @param append logical, if TRUE will append to the end of file_name; if FALSE, will overwrite.
+#' @param verbose logical whether to display messages
+#' @param list_id character, id of list to stream
+#' @param hashtag character, hashtag to stream
+#' @inheritParams get_instance
+#' @details
+#' \describe{
+#'   \item{stream_timeline_public}{stream all public statuses on any instance}
+#'   \item{stream_timeline_hashtag}{stream all statuses containing a specific hashtag}
+#'   \item{stream_timeline_list}{stream the statuses of a list}
+#' }
+#' @export
+#' @examples
+#' \dontrun{
+#' # stream public timeline for 30 seconds
+#' stream_timeline_public(timeout = 30,file_name = "public.json")
+#' # stream timeline of mastodon.social  for 30 seconds
+#' stream_timeline_public(timeout = 30, local = TRUE,
+#'    instance = "mastodon.social", file_name = "social.json")
+#'
+#' # stream hashtag timeline for 30 seconds
+#' stream_timeline_hashtag("rstats", timeout = 30, file_name = "rstats_public.json")
+#' # stream hashtag timeline of mastodon.social  for 30 seconds
+#' stream_timeline_hashtag("rstats", timeout = 30, local = TRUE,
+#'    instance = "fosstodon.org", file_name = "rstats_foss.json")
+#' # json files can be parsed with parse_stream()
+#' parse_stream("rstats_foss.json")
+#' }
+stream_timeline_public <- function(
+    timeout = 30,
+    local = FALSE,
+    file_name = NULL,
+    append = TRUE,
+    instance = NULL,
+    token = NULL,
+    anonymous = FALSE,
+    verbose = TRUE){
+
+  path <- "/api/v1/streaming/public"
+  if(isTRUE(local)){
+    path <- paste0(path,"/local")
+  }
+  params <- list()
+
+  quiet_interrupt(
+    stream_toots(timeout = timeout, file_name = file_name, append = append, token = token,
+                 path = path, params = params, instance = instance, anonymous = anonymous,
+                 verbose = verbose)
+  )
+  invisible(NULL)
+}
+
+#' @rdname stream_timeline
+#' @export
+stream_timeline_hashtag <- function(
+    hashtag = "rstats",
+    timeout = 30,
+    local = FALSE,
+    file_name = NULL,
+    append = TRUE,
+    instance = NULL,
+    token = NULL,
+    anonymous = FALSE,
+    verbose = TRUE){
+
+  path <- "/api/v1/streaming/hashtag"
+  if(isTRUE(local)){
+    path <- paste0(path,"/local")
+  }
+  params <- list(tag = gsub("^#+", "", hashtag))
+
+  quiet_interrupt(
+    stream_toots(timeout = timeout, file_name = file_name, append = append, token = token,
+                 path = path, params = params, instance = instance, anonymous = anonymous,
+                 verbose = verbose)
+  )
+  invisible(NULL)
+}
+
+#' @rdname stream_timeline
+#' @export
+stream_timeline_list <- function(
+    list_id,
+    timeout = 30,
+    file_name = NULL,
+    append = TRUE,
+    instance = NULL,
+    token = NULL,
+    anonymous = FALSE,
+    verbose = TRUE){
+
+  path <- "api/v1/streaming/list"
+  params <- list(list = list_id)
+
+  quiet_interrupt(
+    stream_toots(timeout = timeout, file_name = file_name, append = append, token = token,
+                 path = path, params = params, instance = instance, anonymous = anonymous,
+                 verbose = verbose)
+  )
+  invisible(NULL)
+}
+
+#' Parser of Mastodon stream
+#'
+#' Converts Mastodon stream data (JSON file) into parsed tibble.
+#' @param path Character, name of JSON file with data collected by any [stream_timeline] function.
+#' @export
+#' @seealso `stream_timeline_public()`, `stream_timeline_hashtag()`,`stream_timeline_list()`
+#' @examples
+#' \dontrun{
+#' stream_timeline_public(1,file_name = "stream.json")
+#' parse_stream("stream.json")
+#' }
+parse_stream <- function(path){
+  json <- readLines(path)
+  tbl <- dplyr::bind_rows(lapply(json,function(x) parse_status(jsonlite::fromJSON(x))))
+  tbl[order(tbl[["created_at"]]),]
+}
+
+
+stream_toots <- function(timeout,file_name = NULL, append, token, path, params,
+                                instance = NULL, anonymous = FALSE, verbose = TRUE,...){
+  if (is.null(instance) && anonymous) {
+    stop("provide either an instance or a token")
+  }
+  h <- curl::new_handle(verbose = FALSE)
+  if (is.null(instance)) {
+    token <- check_token_rtoot(token)
+    url <- prepare_url(token$instance)
+    curl::handle_setheaders(h, "Authorization" = paste0("Bearer ",token$bearer))
+  } else {
+    url <- prepare_url(instance)
+  }
+
+  if(is.null(file_name)){
+    file_name <- tempfile(pattern = "stream_toots", fileext = ".json")
+  }
+  sayif(verbose, "Writing to ",file_name)
+  url <- httr::modify_url(url,path = path,query = params)
+
+  stopifnot(is.numeric(timeout), timeout > 0)
+  stop_time <- Sys.time() + timeout
+
+  output <- file(file_name)
+  con <- curl::curl(url,handle = h)
+  open(output,open = if (append) "ab" else "b")
+  open(con = con, "rb", blocking = FALSE)
+  sayif(verbose,"Streaming toots until ",stop_time)
+  n_seen <- 0
+  while(isIncomplete(con) && Sys.time() < stop_time){
+    buf <- readLines(con,warn = FALSE)
+    if(length(buf)){
+      line <- buf[grepl("created_at",buf)] # This seems unstable but rtweet does something similar
+      line <- gsub("^data:\\s+","",line)
+      line <- complete_line(line)
+      writeLines(line,output)
+      n_seen <- n_seen + length(line)
+      if (isTRUE(verbose)) {
+        cat("streamed toots: ",n_seen,"\r")
+      }
+    }
+  }
+  on.exit({
+    close(con)
+    close(output)
+  })
+  invisible()
+}
+
+complete_line <- function(line){
+  line <- line[grepl("\\}$",line)] #delete incomplete lines
+  line <- line[line!=""] # delete empty lines
+  line
+}
+
+quiet_interrupt <- function(code) {
+  tryCatch(code, interrupt = function(e) NULL)
+}

README.Rmd

@@ -43,6 +43,8 @@ You can install the development version of rtoot from GitHub:
 devtools::install_github("schochastics/rtoot")
 ```
 
+*(The current dev version has many more features than the current version on CRAN)*
+
 ## Authenticate
 
 First you should set up your own credentials (see also `vignette("auth")`)
@@ -129,6 +131,23 @@ post_toot(status = "my first rtoot #rstats", media="path/to/media",
 
 You can mark the toot as sensitive by setting `sensitive = TRUE` and add a spoiler text with `spoiler_text`.
 
+## Streaming 
+
+`rtoot` allows to stream statuses from three different streams.
+To get any public status on any instance use `stream_timeline_public()`
+```{r, eval = FALSE}
+stream_timeline_public(timeout = 30,file_name = "public.json")
+```
+the timeout parameter is the time in seconds data should be streamed (set to `Inf` for indefinite streaming). If just the local timeline is needed, use `local=TRUE` and set an instance (or use your own provided by the token).
+
+`stream_timeline_hashtag()` streams all statuses containing a specific hashtag
+
+```{r, eval = FALSE}
+stream_timeline_hashtag("rstats", timeout = 30, file_name = "rstats_public.json")
+```
+
+The statuses are directly written to file as json. The function `parse_stream()` can be used
+to read in and convert a json to a data frame.
 
 ## Pagination
 

README.md

@@ -33,6 +33,9 @@ You can install the development version of rtoot from GitHub:
 devtools::install_github("schochastics/rtoot")
 ```
 
+*(The current dev version has many more features than the current
+version on CRAN)*
+
 ## Authenticate
 
 First you should set up your own credentials (see also
@@ -140,6 +143,31 @@ post_toot(status = "my first rtoot #rstats", media="path/to/media",
 You can mark the toot as sensitive by setting `sensitive = TRUE` and add
 a spoiler text with `spoiler_text`.
 
+## Streaming
+
+`rtoot` allows to stream statuses from three different streams. To get
+any public status on any instance use `stream_timeline_public()`
+
+``` r
+stream_timeline_public(timeout = 30,file_name = "public.json")
+```
+
+the timeout parameter is the time in seconds data should be streamed
+(set to `Inf` for indefinite streaming). If just the local timeline is
+needed, use `local=TRUE` and set an instance (or use your own provided
+by the token).
+
+`stream_timeline_hashtag()` streams all statuses containing a specific
+hashtag
+
+``` r
+stream_timeline_hashtag("rstats", timeout = 30, file_name = "rstats_public.json")
+```
+
+The statuses are directly written to file as json. The function
+`parse_stream()` can be used to read in and convert a json to a data
+frame.
+
 ## Pagination
 
 All relevant functions in the package support pagination of results if