r-使用httr按每分钟计数限制速率

Question

我正在与Discogs API合作，试图为我的收藏提取社区信息(拥有和想要、最低价格等(。

不幸的是，它的速率限制为每分钟25，我无法找到将该限制应用到当前代码中的方法(见下文(。我可以使用sys.sleep((，但我不确定它在代码中的位置。

communityData <- lapply(as.list(collection$release_id), function(obj){
url <- httr::GET(paste0("https://api.discogs.com/releases/", obj))
url <- rjson::fromJSON(rawToChar(url$content))
data.frame(release_id = obj, 
label = url$label[[1]]$name %||% NA,
year = url$year %||% NA, 
title = url$title %||% NA, 
artist_name = url$artist[[1]]$name %||% NA, 
styles = url$styles[[1]] %||% NA,
genre = url$genre[[1]] %||% NA,
average_note = url$community$rating$average %||% NA, 
votes = url$community$rating$count %||% NA, 
want = url$community$want %||% NA, 
have = url$community$have %||% NA, 
lowest_price = url$lowest_price %||% NA, 
country = url$country %||% NA)
}) %>% do.call(rbind, .) %>% 
unique()

如有任何帮助，我们将不胜感激！

Answer 1

在返回值之前直接插入sleep命令应该可以正常工作。这将为您提供查询url、提取信息、睡眠、返回值、重复的模式。阿卡，像这样编辑上面的代码块：

communityData <- lapply(as.list(collection$release_id), function(obj){
url <- httr::GET(paste0("https://api.discogs.com/releases/", obj))
url <- rjson::fromJSON(rawToChar(url$content))
# 1 minute for 25 requests -- ~ 2.4 seconds of sleep between each request
Sys.sleep(2.4)

data.frame(release_id = obj, 
label = url$label[[1]]$name %||% NA,
year = url$year %||% NA, 
title = url$title %||% NA, 
artist_name = url$artist[[1]]$name %||% NA, 
styles = url$styles[[1]] %||% NA,
genre = url$genre[[1]] %||% NA,
average_note = url$community$rating$average %||% NA, 
votes = url$community$rating$count %||% NA, 
want = url$community$want %||% NA, 
have = url$community$have %||% NA, 
lowest_price = url$lowest_price %||% NA, 
country = url$country %||% NA)
}) %>% do.call(rbind, .) %>% 
unique()