r语言 - 在数据帧的多行上使用http

Question

我试图使用R从URL获得响应。我可以使用httr::GET和httr::content成功地编写代码:

library(tidyverse)
library(httr)
test <- GET ("https://www.ebi.ac.uk/cgi-bin/ipd/imgt/hla/dpb_v2.cgi?pid=1&patdpb1=01:01&patdpb2=04:01&did=2&dondpb1=01:01&dondpb2=01:01") 
%>% content(as = "text")

我想对数据帧的每一行都这样做。数据类似如下:

test <- tribble(~case, ~mDPB11cd.recipient, ~mDPB12cd.recipient, ~mDPB11cd.donor, ~mDPB12cd.donor, 
101, "04:01", "01:01", "03:01", "04:01",
102, "04:01", "02:01", "04:01", "01:01",
103, "01:01", "104:01", "03:01", "05:01",)

我已经编写了代码，为每一行组装正确的url，并且可以使用purrr::map获得每个响应:

DPB1_permisive <- test 
%>% mutate (url =  (paste0("https://www.ebi.ac.uk/cgi-bin/ipd/imgt/hla/dpb_v2.cgi?pid=1&patdpb1=", mDPB11cd.recipient, "&patdpb2=", mDPB12cd.recipient, "&did=2&dondpb1=", mDPB11cd.donor, "&dondpb2=", mDPB12cd.donor))) 
%>% mutate (result = (map(url, GET)))

然而，现在我找不到任何方法来使用content来解析我得到的结果。

附加

%>% content(result, as = "text")

在上面的代码中使用会产生一个错误

内容错误(。， result, as = "text"): is.response(x)不是TRUE

似乎URL的结果没有正确地写入数据帧中。"result"列显示为类型"列表"，";每行的值为S3: response>.">

如何让content解析响应?

Answer 1

您可以使用map从GET请求中获取数据。

library(tidyverse)
library(httr)
test %>% 
mutate(url = paste0("https://www.ebi.ac.uk/cgi-bin/ipd/imgt/hla/dpb_v2.cgi?pid=1&patdpb1=", mDPB11cd.recipient, "&patdpb2=", mDPB12cd.recipient, "&did=2&dondpb1=", mDPB11cd.donor, "&dondpb2=", mDPB12cd.donor),
result = map(url, GET), 
data = map(result, content, as = "text"))
#   case mDPB11cd.recipie… mDPB12cd.recipie… mDPB11cd.donor mDPB12cd.donor url                      result data 
#  <dbl> <chr>             <chr>             <chr>          <chr>          <chr>                    <list> <lis>
#1   101 04:01             01:01             03:01          04:01          https://www.ebi.ac.uk/c… <resp… <chr…
#2   102 04:01             02:01             04:01          01:01          https://www.ebi.ac.uk/c… <resp… <chr…
#3   103 01:01             104:01            03:01          05:01          https://www.ebi.ac.uk/c… <resp… <chr…