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## These are tests that require socket and internet functionality, and
## a working Internet connection.
## We attempt to test for those.
if(!capabilities()["http/ftp"]) {
warning("no internet capabilities")
q()
}
if(.Platform$OS.type == "unix" &&
is.null(nsl("cran.r-project.org"))) q()
# test do_download.
nrow(available.packages(contrib.url("http://cran.r-project.org")))
# test url connections on http
zz <- url("http://cran.r-project.org/")
readLines(zz)
close(zz)
## check graceful failure:
try(zz <- url("http://foo.bar", "r"))
# and via read.table, test http and ftp.
read.table("http://www.stats.ox.ac.uk/pub/datasets/csb/ch11b.dat")
read.table("ftp://ftp.stats.ox.ac.uk/pub/datasets/csb/ch11b.dat")
## everything from here on is directly over sockets
if(!capabilities("sockets")) stop("no socket capabilities")
# do the same thing via sockets (cut-down httpclient)
httpget <- function (url, port = 80)
{
urlel <- strsplit(url, "/")[[1]]
if (urlel[1] != "http:") stop("Not an http:// URL")
host <- urlel[3]
rurl <- paste(c("", urlel[-(1:3)]), collapse = "/")
a <- make.socket(host, port = port)
on.exit(close.socket(a))
headreq <- paste("HEAD", rurl, "HTTP/1.0\r\nConnection: Keep-Alive\r\nAccept: text/plain\r\n\r\n")
write.socket(a, headreq)
head <- read.socket(a, maxlen = 8000)
b <- strsplit(head, "\n")[[1]]
if (length(grep("200 OK", b[1])) == 0) stop(b[1])
len <- as.numeric(strsplit(grep("Content-Length", b, value = TRUE),
":")[[1]][2])
getreq <- paste("GET", rurl, "HTTP/1.0\r\nConnection: Keep-Alive\r\nAccept: text/plain\r\n\r\n")
write.socket(a, getreq)
junk <- read.socket(a, maxlen = nchar(head))
data <- ""
b <- strsplit(c(head, junk), "\n")
nn <- length(b[[1]])
if (length(b[[2]]) > nn)
data <- paste(b[[2]][-(1:nn)], collapse = "\n")
while (nchar(data) < len) {
data <- paste(data, read.socket(a, maxlen = len - nchar(data)),
sep = "")
}
strsplit(data, "\n")[[1]]
}
if(nzchar(Sys.getenv("http_proxy")) || nzchar(Sys.getenv("HTTP_PROXY"))) {
cat("http proxy is set, so skip test of http over sockets\n")
} else {
httpget("http://www.stats.ox.ac.uk/pub/datasets/csb/ch11b.dat")
}
finger <- function(user, host = "localhost", port = 79, print = TRUE)
{
if (!is.character(user))
stop("user name must be a string")
user <- paste(user,"\r\n")
socket <- make.socket(host, port)
on.exit(close.socket(socket))
write.socket(socket, user)
output <- character(0)
repeat{
ss <- read.socket(socket)
if (ss == "") break
output <- paste(output, ss)
}
close.socket(socket)
if (print) cat(output)
invisible(output)
}
try(finger("root")) ## only works if your site provides a finger daemon
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