如何将服务器响应保存到动态变量答案

【问题标题】：How to save server responses to a dynamic variable如何将服务器响应保存到动态变量
【发布时间】：2023-02-14 23:25:52
【问题描述】：

datasets_uids <- c("b0ozQvcc7nP","D9CrlbX7KBV")
服务器 <- c("url1","url2")

for (i in 1:length(datasets_uids)) {
  
  for(j in 1:length(servers)){
    
    assign(paste("postOrgUnitsToDataset",j,sep="_"),httr::POST(paste0(servers[j],"dhis/api/dataSets/",datasets_uids[i],"/organisationUnits"),                                       body=httr::upload_file("file.json"),
                                      httr::verbose(),
                                      httr::authenticate("username","password", type = "basic"),
                                      httr::content_type("application/json"),
                                      httr::progress("up"),
                                      httr::set_config(httr::config(ssl_verifypeer = 0L))
    ))
  }
}

我希望将所有四个回复保存如下

postOrgUnitsToDataset_1=response1
postOrgUnitsToDataset_2=response2
postOrgUnitsToDataset_3=response3
postOrgUnitsToDataset_4=response4

但是响应被覆盖并保存在以下两个响应中

postOrgUnitsToDataset_1=response3
postOrgUnitsToDataset_2=response4

那么我如何修改上面的代码以将所有回复保存在postOrgUnitsToDataset_1,postOrgUnitsToDataset_2,postOrgUnitsToDataset_3,postOrgUnitsToDataset_4

【问题讨论】：

标签： r

【解决方案1】：

使用assign 创建全局变量通常不是一个好主意。在 R 中处理列表中的数据要容易得多。一种迭代创建列表的方法是lapply。在这里，我们首先创建所有 URL，然后为每个 URL 发送一个请求

datasets_uids <- c("b0ozQvcc7nP","D9CrlbX7KBV")
servers <- c("url1","url2")

requests <- expand.grid(uid=datasets_uids, server=servers) |>
  transform(url=paste0(server,"dhis/api/dataSets/",uid,"/organisationUnits"))

postOrgUnitsToDataset <- lapply(requests$url, function(url) {
  httr::POST(url,
     body=httr::upload_file("file.json"),
     httr::verbose(),
     httr::authenticate("username","password", type = "basic"),
     httr::content_type("application/json"),
     httr::progress("up"),
     httr::set_config(httr::config(ssl_verifypeer = 0L))
)})

然后所有数据将在postOrgUnitsToDataset[[1]]、postOrgUnitsToDataset[[2]]等中。它的顺序与requests data.frame 中显示的记录顺序相同

【讨论】：