使用R从ftp-server下载最新的文件

问题描述：

我有一个名为

FileA2014-03-05-10-24-12
FileB2014-03-06-10-25-12

哪里的部分2014-03-05-10 -24-12表示年/日/月/小时/分/秒/。这些文件驻留在ftp服务器上。我想使用R连接到ftp服务器，并根据日期下载任何最新的文件。

Where the part "2014-03-05-10-24-12" means "Year/Day/Month/Hours/Minutes/Seconds/". These files reside on a ftp-server. I would like to use R to connect to the ftp-server and download whatever file is newest based on date.

我已经开始尝试列出内容，使用RCurl和dirlistonly。下一步将尝试解析并找到最新的文件。不完全没有...

I have started trying to list the content, using RCurl and dirlistonly. Next step will be to try to parse and find the newest file. Not quite there yet...

library(RCurl)
getURL("ftpserver/",verbose=TRUE,dirlistonly = TRUE)

答

This should work

library(RCurl)
url <- "ftp://yourServer"
userpwd <- "yourUser:yourPass"
filenames <- getURL(url, userpwd = userpwd,
             ftp.use.epsv = FALSE,dirlistonly = TRUE)

times<-lapply(strsplit(filenames,"[-.]"),function(x){
  time<-paste(c(substr(x[1], nchar(x[1])-3, nchar(x[1])),x[2:6]),
        collapse="-")
  time<-as.POSIXct(time, "%Y-%m-%d-%H-%M-%S", tz="GMT")
})
ind <- which.max(times)
dat <- try(getURL(paste(url,filenames[ind],sep=""), userpwd = userpwd))

所以 dat 现在包含最新的文件

So datis now containing the newest file

使其可重现：所有其他人都可以使用t他不是上层使用

filenames<-c("FileA2014-03-05-10-24-12.csv","FileB2014-03-06-10-25-12.csv")

使用R从ftp-server下载最新的文件

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