如何在给定时间段内删除所有subreddit帖子

Question

我有功能在2014-11-01和2015-10-31之间刮掉比特币subreddit中的所有帖子.

但是,我只能提取大约990个帖子,这些帖子可以追溯到10月25日.我不明白发生了什么.在参考https://github.com/reddit/reddit/wiki/API之后,我在每个提取之间包含了一个15秒的Sys.sleep ,但无济于事.

此外,我尝试从另一个subreddit(健身)刮,但它也返回约900个帖子.

require(jsonlite)
require(dplyr)

getAllPosts <- function() {
    url <- "https://www.reddit.com/r/bitcoin/search.json?q=timestamp%3A1414800000..1446335999&sort=new&restrict_sr=on&rank=title&syntax=cloudsearch&limit=100"
    extract <- fromJSON(url)
    posts <- extract$data$children$data %>% dplyr::select(name, author,   num_comments, created_utc,
                                             title, selftext)  
    after <- posts[nrow(posts),1]
    url.next <- paste0("https://www.reddit.com/r/bitcoin/search.json?q=timestamp%3A1414800000..1446335999&sort=new&restrict_sr=on&rank=title&syntax=cloudsearch&after=",after,"&limit=100")
    extract.next <- fromJSON(url.next)
    posts.next <- extract.next$data$children$data

    # execute while loop as long as there are any rows in the data frame
    while (!is.null(nrow(posts.next))) {
        posts.next <- posts.next %>% dplyr::select(name, author, num_comments, created_utc, 
                                    title, selftext)
        posts <- rbind(posts, posts.next)
        after <- posts[nrow(posts),1]
        url.next <- paste0("https://www.reddit.com/r/bitcoin/search.json?q=timestamp%3A1414800000..1446335999&sort=new&restrict_sr=on&rank=title&syntax=cloudsearch&after=",after,"&limit=100")
        Sys.sleep(15)
        extract <- fromJSON(url.next)
        posts.next <- extract$data$children$data
    }
    posts$created_utc <- as.POSIXct(posts$created_utc, origin="1970-01-01")
    return(posts)
}

posts <- getAllPosts()

reddit是否有某种限制,我正在打？

Answer 1

是的，所有 Reddit 列表（帖子、评论等）的条目上限为 1000 条；出于性能原因，它们本质上只是缓存列表，而不是查询。

为了解决这个问题，您需要根据时间戳进行一些巧妙的搜索。